iOS总结
转自 http://www.jianshu.com/p/1ff9e44ccc78 杂雾无尘
1、禁止手机睡眠
[UIApplication sharedApplication].idleTimerDisabled = YES;
2、隐藏某行cell
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
// 如果是你需要隐藏的那一行,返回高度为0
if(indexPath.row == YouWantToHideRow)
return 0;
return 44;
}
// 然后再你需要隐藏cell的时候调用
[self.tableView beginUpdates];
[self.tableView endUpdates];
3、禁用button高亮
button.adjustsImageWhenHighlighted = NO;
或者在创建的时候
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
4、tableview遇到这种报错failed to obtain a cell from its dataSource
是因为你的cell被调用的早了。先循环使用了cell,后又创建cell。顺序错了
可能原因:1、xib的cell没有注册 2、内存中已经有这个cell的缓存了(也就是说通过你的cellId找到的cell并不是你想要的类型),这时候需要改下cell的标识
5、cocoa pods报这个错误:unable to access 'https://github.com/facebook/pop.git/': Operation timed out after 0 milliseconds with 0 out of 0 bytes received
解决办法:原因可能是网络问题,网络请求超时了,只需要重试就行了
6、cocoa pods 出现ERROR: While executing gem ... (Errno::EPERM)
7、动画切换window的根控制器
// options是动画选项
[UIView transitionWithView:[UIApplication sharedApplication].keyWindow duration:0.5f options:UIViewAnimationOptionTransitionCrossDissolve animations:^{
BOOL oldState = [UIView areAnimationsEnabled];
[UIView setAnimationsEnabled:NO];
[UIApplication sharedApplication].keyWindow.rootViewController = [RootViewController new];
[UIView setAnimationsEnabled:oldState];
} completion:^(BOOL finished) {
}];
8、去除数组中重复的对象
NSArray *newArr = [oldArr valueForKeyPath:@“@distinctUnionOfObjects.self"];
9、编译的时候遇到 no such file or directory: /users/apple/XXX
是因为编译的时候,在此路径下找不到这个文件,解决这个问题,首先是是要检查缺少的文件是不是在工程中,如果不在工程中,需要从本地拖进去,如果发现已经存在工程中了,或者拖进去还是报错,这时候需要去build phases中搜索这个文件,这时候很可能会搜出现两个相同的文件,这时候,有一个路径是正确的,删除另外一个即可。如果删除了还是不行,需要把两个都删掉,然后重新往工程里拖进这个文件即可
![](http://upload-images.jianshu.io/upload_images/1432270-6f8de370bcd7af82.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
10、iOS8系统中,tableView最好实现下-tableView: heightForRowAtIndexPath:这个代理方法,要不然在iOS8中可能就会出现显示不全或者无法响应事件的问题
11、iOS8中实现侧滑功能的时候这个方法必须实现,要不然在iOS8中无法侧滑
// 必须写的方法,和editActionsForRowAtIndexPath配对使用,里面什么不写也行
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
}
12、三个通知
NSSystemTimeZoneDidChangeNotification监听修改时间界面的两个按钮状态变化
UIApplicationSignificantTimeChangeNotification 监听用户改变时间 (只要点击自动设置按钮就会调用) NSSystemClockDidChangeNotification 监听用户修改时间(时间不同才会调用)
13、SDWebImage本地缓存有时候会害人。如果之前缓存过一张图片,即使下次服务器换了这张图片,但是图片url没换,用sdwebimage下载下来的还是以前那张,所以遇到这种问题,不要先去怼服务器,清空下缓存再试就好了。
14、上线前注意:
1)、删掉代码中所有的测试代码
2)、如果后台有审核模式,提醒后台开启此模式
3)、主流程再跑一跑
4)、全局搜索waring,检查所有标记waring的地方
15、跳进app权限设置
// 跳进app设置
if (UIApplicationOpenSettingsURLString != NULL) {
UIApplication *application = [UIApplication sharedApplication];
NSURL *URL = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) {
[application openURL:URL options:@{}
completionHandler:nil];
} else {
[application openURL:URL];
}
}
16、给一个view截图
UIGraphicsBeginImageContextWithOptions(view.bounds.size, YES, 0.0);
[view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
17、开发中如果要动态修改tableView的tableHeaderView或者tableFooterView的高度,需要给tableView重新设置,而不是直接更改高度。正确的做法是重新设置一下tableView.tableFooterView = 更改过高度的view。为什么?其实在iOS8以上直接改高度是没有问题的,在iOS8中出现了contentSize不准确的问题,这是解决办法。
18、注意对象为nil的时候,调用此对象分类的方法不会执行
19、collectionView的内容小于其宽高的时候是不能滚动的,设置可以滚动:
collectionView.alwaysBounceHorizontal = YES;
collectionView.alwaysBounceVertical = YES;
20、设置navigationBar上的title颜色和大小
[self.navigationController.navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName : [UIColor youColor], NSFontAttributeName : [UIFont systemFontOfSize:15]}]
21、颜色转图片
+ (UIImage *)cl_imageWithColor:(UIColor *)color {
CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [color CGColor]);
CGContextFillRect(context, rect);
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
22、view设置圆角
#define ViewBorderRadius(View, Radius, Width, Color)\
\
[View.layer setCornerRadius:(Radius)];\
[View.layer setMasksToBounds:YES];\
[View.layer setBorderWidth:(Width)];\
[View.layer setBorderColor:[Color CGColor]] // view圆角
23、强/弱引用
#define WeakSelf(type) __weak typeof(type) weak##type = type; // weak
#define StrongSelf(type) __strong typeof(type) type = weak##type; // strong
24、由角度转换弧度
#define DegreesToRadian(x) (M_PI * (x) / 180.0)
25、由弧度转换角度
#define RadianToDegrees(radian) (radian*180.0)/(M_PI)
26、获取图片资源
#define GetImage(imageName) [UIImage imageNamed:[NSString stringWithFormat:@"%@",imageName]]
27、获取temp
#define PathTemp NSTemporaryDirectory()
28、获取沙盒 Document
#define PathDocument [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject]
29、获取沙盒 Cache
#define PathCache [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) firstObject]
30、GCD代码只执行一次
#define kDISPATCH_ONCE_BLOCK(onceBlock) static dispatch_once_t onceToken; dispatch_once(&onceToken, onceBlock);
31、自定义NSLog
#ifdef DEBUG
#define NSLog(fmt, ...) NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)
#else
#define NSLog(...)
#endif
32、Font
#define FontL(s) [UIFont systemFontOfSize:s weight:UIFontWeightLight]
#define FontR(s) [UIFont systemFontOfSize:s weight:UIFontWeightRegular]
#define FontB(s) [UIFont systemFontOfSize:s weight:UIFontWeightBold]
#define FontT(s) [UIFont systemFontOfSize:s weight:UIFontWeightThin]
#define Font(s) FontL(s)
33、FORMAT
#define FORMAT(f, ...) [NSString stringWithFormat:f, ## __VA_ARGS__]
34、在主线程上运行
#define kDISPATCH_MAIN_THREAD(mainQueueBlock) dispatch_async(dispatch_get_main_queue(), mainQueueBlock);
35、开启异步线程
#define kDISPATCH_GLOBAL_QUEUE_DEFAULT(globalQueueBlock) dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), globalQueueBlocl);
36、通知
#define NOTIF_ADD(n, f) [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(f) name:n object:nil]
#define NOTIF_POST(n, o) [[NSNotificationCenter defaultCenter] postNotificationName:n object:o]
#define NOTIF_REMV() [[NSNotificationCenter defaultCenter] removeObserver:self]
37、随机颜色
+ (UIColor *)RandomColor {
NSInteger aRedValue = arc4random() % 255;
NSInteger aGreenValue = arc4random() % 255;
NSInteger aBlueValue = arc4random() % 255;
UIColor *randColor = [UIColor colorWithRed:aRedValue / 255.0f green:aGreenValue / 255.0f blue:aBlueValue / 255.0f alpha:1.0f];
return randColor;
}
38、获取window
+(UIWindow*)getWindow {
UIWindow* win = nil; //[UIApplication sharedApplication].keyWindow;
for (id item in [UIApplication sharedApplication].windows) {
if ([item class] == [UIWindow class]) {
if (!((UIWindow*)item).hidden) {
win = item;
break;
}
}
}
return win;
}
39、修改textField的placeholder的字体颜色、大小
[textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];
[textField setValue:[UIFont boldSystemFontOfSize:16] forKeyPath:@"_placeholderLabel.font"];
40、统一收起键盘
[[[UIApplication sharedApplication] keyWindow] endEditing:YES];
41、控制屏幕旋转,在控制器中写
/** 是否支持自动转屏 */
- (BOOL)shouldAutorotate {
return YES;
}
/** 支持哪些屏幕方向 */
- (UIInterfaceOrientationMask)supportedInterfaceOrientations {
return UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight;
}
/** 默认的屏幕方向(当前ViewController必须是通过模态出来的UIViewController(模态带导航的无效)方式展现出来的,才会调用这个方法) */
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {
return UIInterfaceOrientationLandscapeLeft | UIInterfaceOrientationLandscapeRight;
}
42、获取app缓存大小
- (CGFloat)getCachSize {
NSUInteger imageCacheSize = [[SDImageCache sharedImageCache] getSize];
//获取自定义缓存大小
//用枚举器遍历 一个文件夹的内容
//1.获取 文件夹枚举器
NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"];
NSDirectoryEnumerator *enumerator = [[NSFileManager defaultManager] enumeratorAtPath:myCachePath];
__block NSUInteger count = 0;
//2.遍历
for (NSString *fileName in enumerator) {
NSString *path = [myCachePath stringByAppendingPathComponent:fileName];
NSDictionary *fileDict = [[NSFileManager defaultManager] attributesOfItemAtPath:path error:nil];
count += fileDict.fileSize;//自定义所有缓存大小
}
// 得到是字节 转化为M
CGFloat totalSize = ((CGFloat)imageCacheSize+count)/1024/1024;
return totalSize;
}
43、清理app缓存
- (void)handleClearView {
//删除两部分
//1.删除 sd 图片缓存
//先清除内存中的图片缓存
[[SDImageCache sharedImageCache] clearMemory];
//清除磁盘的缓存
[[SDImageCache sharedImageCache] clearDisk];
//2.删除自己缓存
NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"];
[[NSFileManager defaultManager] removeItemAtPath:myCachePath error:nil];
}
44、模型转字典
static NSSet *classes;
- (NSMutableDictionary *)getParameterDictionary {
NSMutableDictionary *dict = [NSMutableDictionary dictionary];
Class c = self.class;
while (c) {
unsigned count;
objc_property_t *properties = class_copyPropertyList([c class], &count);
for (int i = 0; i < count; i++) {
NSString *key = [NSString stringWithUTF8String:property_getName(properties[i])];
dict[key] = [self valueForKey:key];
}
free(properties);
// 获得父类
c = class_getSuperclass(c);
if ([self isClassFromFoundation:c]) break;
}
return dict;
}
- (BOOL)isClassFromFoundation:(Class)c
{
if (c == [NSObject class] || c == [NSManagedObject class]) return YES;
__block BOOL result = NO;
[[self foundationClasses] enumerateObjectsUsingBlock:^(Class foundationClass, BOOL *stop) {
if ([c isSubclassOfClass:foundationClass]) {
result = YES;
*stop = YES;
}
}];
return result;
}
- (NSSet *)foundationClasses
{
if (classes == nil) {
// 集合中没有NSObject,因为几乎所有的类都是继承自NSObject,具体是不是NSObject需要特殊判断
classes = [NSSet setWithObjects:
[NSURL class],
[NSDate class],
[NSValue class],
[NSData class],
[NSError class],
[NSArray class],
[NSDictionary class],
[NSString class],
[NSAttributedString class], nil];
}
return classes;
}
45、交换两个方法实现
Class aClass = [self class];
SEL originalSelector = @selector(viewWillAppear:);
SEL swizzledSelector = @selector(xxx_viewWillAppear:);
Method originalMethod = class_getInstanceMethod(aClass, originalSelector);
Method swizzledMethod = class_getInstanceMethod(aClass, swizzledSelector);
BOOL didAddMethod =
class_addMethod(aClass,
originalSelector,
method_getImplementation(swizzledMethod),
method_getTypeEncoding(swizzledMethod));
if (didAddMethod) {
class_replaceMethod(aClass,
swizzledSelector,
method_getImplementation(originalMethod),
method_getTypeEncoding(originalMethod));
} else {
method_exchangeImplementations(originalMethod, swizzledMethod);
}
46、打印百分号和引号
NSLog(@"%%");
NSLog(@"\"");
47、几个常用权限判断
if ([CLLocationManager authorizationStatus] ==kCLAuthorizationStatusDenied) {
NSLog(@"没有定位权限");
}
AVAuthorizationStatus statusVideo = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];
if (statusVideo == AVAuthorizationStatusDenied) {
NSLog(@"没有摄像头权限");
}
//是否有麦克风权限
AVAuthorizationStatus statusAudio = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeAudio];
if (statusAudio == AVAuthorizationStatusDenied) {
NSLog(@"没有录音权限");
}
[PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
if (status == PHAuthorizationStatusDenied) {
NSLog(@"没有相册权限");
}
}];
48、获取手机型号
+ (NSString *)getDeviceInfo {
struct utsname systemInfo;
uname(&systemInfo);
NSString *platform = [NSString stringWithCString:systemInfo.machine encoding:NSASCIIStringEncoding];
if ([platform isEqualToString:@"iPhone1,1"]) return @"iPhone 2G";
if ([platform isEqualToString:@"iPhone1,2"]) return @"iPhone 3G";
if ([platform isEqualToString:@"iPhone2,1"]) return @"iPhone 3GS";
if ([platform isEqualToString:@"iPhone3,1"]) return @"iPhone 4";
if ([platform isEqualToString:@"iPhone3,2"]) return @"iPhone 4";
if ([platform isEqualToString:@"iPhone3,3"]) return @"iPhone 4";
if ([platform isEqualToString:@"iPhone4,1"]) return @"iPhone 4S";
if ([platform isEqualToString:@"iPhone5,1"]) return @"iPhone 5";
if ([platform isEqualToString:@"iPhone5,2"]) return @"iPhone 5";
if ([platform isEqualToString:@"iPhone5,3"]) return @"iPhone 5c";
if ([platform isEqualToString:@"iPhone5,4"]) return @"iPhone 5c";
if ([platform isEqualToString:@"iPhone6,1"]) return @"iPhone 5s";
if ([platform isEqualToString:@"iPhone6,2"]) return @"iPhone 5s";
if ([platform isEqualToString:@"iPhone7,1"]) return @"iPhone 6 Plus";
if ([platform isEqualToString:@"iPhone7,2"]) return @"iPhone 6";
if ([platform isEqualToString:@"iPhone8,1"]) return @"iPhone 6s";
if ([platform isEqualToString:@"iPhone8,2"]) return @"iPhone 6s Plus";
// 日行两款手机型号均为日本独占,可能使用索尼FeliCa支付方案而不是苹果支付
if ([platform isEqualToString:@"iPhone9,1"]) return @"国行、日版、港行iPhone 7";
if ([platform isEqualToString:@"iPhone9,2"]) return @"港行、国行iPhone 7 Plus";
if ([platform isEqualToString:@"iPhone9,3"]) return @"美版、台版iPhone 7";
if ([platform isEqualToString:@"iPhone9,4"]) return @"美版、台版iPhone 7 Plus";
if ([platform isEqualToString:@"iPhone8,4"]) return @"iPhone SE";
if ([platform isEqualToString:@"iPod1,1"]) return @"iPod Touch 1G";
if ([platform isEqualToString:@"iPod2,1"]) return @"iPod Touch 2G";
if ([platform isEqualToString:@"iPod3,1"]) return @"iPod Touch 3G";
if ([platform isEqualToString:@"iPod4,1"]) return @"iPod Touch 4G";
if ([platform isEqualToString:@"iPod5,1"]) return @"iPod Touch 5G";
if ([platform isEqualToString:@"iPad1,1"]) return @"iPad 1G";
if ([platform isEqualToString:@"iPad2,1"]) return @"iPad 2";
if ([platform isEqualToString:@"iPad2,2"]) return @"iPad 2";
if ([platform isEqualToString:@"iPad2,3"]) return @"iPad 2";
if ([platform isEqualToString:@"iPad2,4"]) return @"iPad 2";
if ([platform isEqualToString:@"iPad2,5"]) return @"iPad Mini 1G";
if ([platform isEqualToString:@"iPad2,6"]) return @"iPad Mini 1G";
if ([platform isEqualToString:@"iPad2,7"]) return @"iPad Mini 1G";
if ([platform isEqualToString:@"iPad3,1"]) return @"iPad 3";
if ([platform isEqualToString:@"iPad3,2"]) return @"iPad 3";
if ([platform isEqualToString:@"iPad3,3"]) return @"iPad 3";
if ([platform isEqualToString:@"iPad3,4"]) return @"iPad 4";
if ([platform isEqualToString:@"iPad3,5"]) return @"iPad 4";
if ([platform isEqualToString:@"iPad3,6"]) return @"iPad 4";
if ([platform isEqualToString:@"iPad4,1"]) return @"iPad Air";
if ([platform isEqualToString:@"iPad4,2"]) return @"iPad Air";
if ([platform isEqualToString:@"iPad4,3"]) return @"iPad Air";
if ([platform isEqualToString:@"iPad4,4"]) return @"iPad Mini 2G";
if ([platform isEqualToString:@"iPad4,5"]) return @"iPad Mini 2G";
if ([platform isEqualToString:@"iPad4,6"]) return @"iPad Mini 2G";
if ([platform isEqualToString:@"i386"]) return @"iPhone Simulator";
if ([platform isEqualToString:@"x86_64"]) return @"iPhone Simulator";
return platform;
}
49、长按复制功能
- (void)viewDidLoad
{
[self.view addGestureRecognizer:[[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(pasteBoard:)]];
}
- (void)pasteBoard:(UILongPressGestureRecognizer *)longPress {
if (longPress.state == UIGestureRecognizerStateBegan) {
UIPasteboard *pasteboard = [UIPasteboard generalPasteboard];
pasteboard.string = @"需要复制的文本";
}
}
50、cocoapods升级
在终端执行 sudo gem install -n / usr / local / bin cocoapods --pre
51、设置启动页后,依然显示之前的
删除app,手机重启,重新安装
52、判断图片类型
//通过图片Data数据第一个字节 来获取图片扩展名
- (NSString *)contentTypeForImageData:(NSData *)data
{
uint8_t c;
[data getBytes:&c length:1];
switch (c)
{
case 0xFF:
return @"jpeg";
case 0x89:
return @"png";
case 0x47:
return @"gif";
case 0x49:
case 0x4D:
return @"tiff";
case 0x52:
if ([data length] < 12) {
return nil;
}
NSString *testString = [[NSString alloc] initWithData:[data subdataWithRange:NSMakeRange(0, 12)] encoding:NSASCIIStringEncoding];
if ([testString hasPrefix:@"RIFF"]
&& [testString hasSuffix:@"WEBP"])
{
return @"webp";
}
return nil;
}
return nil;
}
53、获取手机和app信息
NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
CFShow(infoDictionary);
// app名称
NSString *app_Name = [infoDictionary objectForKey:@"CFBundleDisplayName"];
// app版本
NSString *app_Version = [infoDictionary objectForKey:@"CFBundleShortVersionString"];
// app build版本
NSString *app_build = [infoDictionary objectForKey:@"CFBundleVersion"];
//手机序列号
NSString* identifierNumber = [[UIDevice currentDevice] uniqueIdentifier];
NSLog(@"手机序列号: %@",identifierNumber);
//手机别名: 用户定义的名称
NSString* userPhoneName = [[UIDevice currentDevice] name];
NSLog(@"手机别名: %@", userPhoneName);
//设备名称
NSString* deviceName = [[UIDevice currentDevice] systemName];
NSLog(@"设备名称: %@",deviceName );
//手机系统版本
NSString* phoneVersion = [[UIDevice currentDevice] systemVersion];
NSLog(@"手机系统版本: %@", phoneVersion);
//手机型号
NSString* phoneModel = [[UIDevice currentDevice] model];
NSLog(@"手机型号: %@",phoneModel );
//地方型号 (国际化区域名称)
NSString* localPhoneModel = [[UIDevice currentDevice] localizedModel];
NSLog(@"国际化区域名称: %@",localPhoneModel );
NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
// 当前应用名称
NSString *appCurName = [infoDictionary objectForKey:@"CFBundleDisplayName"];
NSLog(@"当前应用名称:%@",appCurName);
// 当前应用软件版本 比如:1.0.1
NSString *appCurVersion = [infoDictionary objectForKey:@"CFBundleShortVersionString"];
NSLog(@"当前应用软件版本:%@",appCurVersion);
// 当前应用版本号码 int类型
NSString *appCurVersionNum = [infoDictionary objectForKey:@"CFBundleVersion"];
NSLog(@"当前应用版本号码:%@",appCurVersionNum);
54、获取一个类的所有属性
id LenderClass = objc_getClass("Lender");
unsigned int outCount, i;
objc_property_t *properties = class_copyPropertyList(LenderClass, &outCount);
for (i = 0; i < outCount; i++) {
objc_property_t property = properties[i];
fprintf(stdout, "%s %s\n", property_getName(property), property_getAttributes(property));
}
55、image圆角
- (UIImage *)circleImage
{
// NO代表透明
UIGraphicsBeginImageContextWithOptions(self.size, NO, 1);
// 获得上下文
CGContextRef ctx = UIGraphicsGetCurrentContext();
// 添加一个圆
CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);
// 方形变圆形
CGContextAddEllipseInRect(ctx, rect);
// 裁剪
CGContextClip(ctx);
// 将图片画上去
[self drawInRect:rect];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
56、image拉伸
+ (UIImage *)resizableImage:(NSString *)imageName
{
UIImage *image = [UIImage imageNamed:imageName];
CGFloat imageW = image.size.width;
CGFloat imageH = image.size.height;
return [image resizableImageWithCapInsets:UIEdgeInsetsMake(imageH * 0.5, imageW * 0.5, imageH * 0.5, imageW * 0.5) resizingMode:UIImageResizingModeStretch];
}
57、JSON字符串转字典
+ (NSDictionary *)parseJSONStringToNSDictionary:(NSString *)JSONString {
NSData *JSONData = [JSONString dataUsingEncoding:NSUTF8StringEncoding];
NSDictionary *responseJSON = [NSJSONSerialization JSONObjectWithData:JSONData options:NSJSONReadingMutableLeaves error:nil];
return responseJSON;
}
58、身份证号验证
- (BOOL)validateIdentityCard {
BOOL flag;
if (self.length <= 0) {
flag = NO;
return flag;
}
NSString *regex2 = @"^(\\d{14}|\\d{17})(\\d|[xX])$";
NSPredicate *identityCardPredicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",regex2];
return [identityCardPredicate evaluateWithObject:self];
}
59、获取设备mac地址
+ (NSString *)macAddress {
int mib[6];
size_t len;
char *buf;
unsigned char *ptr;
struct if_msghdr *ifm;
struct sockaddr_dl *sdl;
mib[0] = CTL_NET;
mib[1] = AF_ROUTE;
mib[2] = 0;
mib[3] = AF_LINK;
mib[4] = NET_RT_IFLIST;
if((mib[5] = if_nametoindex("en0")) == 0) {
printf("Error: if_nametoindex error\n");
return NULL;
}
if(sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {
printf("Error: sysctl, take 1\n");
return NULL;
}
if((buf = malloc(len)) == NULL) {
printf("Could not allocate memory. Rrror!\n");
return NULL;
}
if(sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
printf("Error: sysctl, take 2");
return NULL;
}
ifm = (struct if_msghdr *)buf;
sdl = (struct sockaddr_dl *)(ifm + 1);
ptr = (unsigned char *)LLADDR(sdl);
NSString *outstring = [NSString stringWithFormat:@"%02X:%02X:%02X:%02X:%02X:%02X",
*ptr, *(ptr+1), *(ptr+2), *(ptr+3), *(ptr+4), *(ptr+5)];
free(buf);
return outstring;
}
60、导入自定义字体库
1、找到你想用的字体的 ttf 格式,拖入工程
2、在工程的plist中增加一行数组,“Fonts provided by application”
3、为这个key添加一个item,value为你刚才导入的ttf文件名
4、直接使用即可:label.font = [UIFont fontWithName:@"你刚才导入的ttf文件名" size:20.0];
61、拿到当前正在显示的控制器,不管是push进去的,还是present进去的都能拿到
- (UIViewController *)getVisibleViewControllerFrom:(UIViewController*)vc {
if ([vc isKindOfClass:[UINavigationController class]]) {
return [self getVisibleViewControllerFrom:[((UINavigationController*) vc) visibleViewController]];
}else if ([vc isKindOfClass:[UITabBarController class]]){
return [self getVisibleViewControllerFrom:[((UITabBarController*) vc) selectedViewController]];
} else {
if (vc.presentedViewController) {
return [self getVisibleViewControllerFrom:vc.presentedViewController];
} else {
return vc;
}
}
}
62、runtime为一个类动态添加属性
// 动态添加属性的本质是: 让对象的某个属性与值产生关联
objc_setAssociatedObject(self, WZBPlaceholderViewKey, placeholderView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
63、获取runtime为一个类动态添加的属性
objc_getAssociatedObject(self, WZBPlaceholderViewKey);
64、KVO监听某个对象的属性
// 添加监听者
[self addObserver:self forKeyPath:property options:NSKeyValueObservingOptionNew context:nil];
// 当监听的属性值变化的时候会来到这个方法
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
if ([keyPath isEqualToString:@"property"]) {
[self textViewTextChange];
} else {
}
}
65、Reachability判断网络状态
NetworkStatus status = [[Reachability reachabilityForInternetConnection] currentReachabilityStatus];
if (status == NotReachable) {
NSLog(@"当前设备无网络");
}
if (status == ReachableViaWiFi) {
NSLog(@"当前wifi网络");
}
if (status == ReachableViaWWAN) {
NSLog(@"当前蜂窝移动网络");
}
66、AFNetworking监听网络状态
// 监听网络状况
AFNetworkReachabilityManager *mgr = [AFNetworkReachabilityManager sharedManager];
[mgr setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {
switch (status) {
case AFNetworkReachabilityStatusUnknown:
break;
case AFNetworkReachabilityStatusNotReachable: {
[SVProgressHUD showInfoWithStatus:@"当前设备无网络"];
}
break;
case AFNetworkReachabilityStatusReachableViaWiFi:
[SVProgressHUD showInfoWithStatus:@"当前Wi-Fi网络"];
break;
case AFNetworkReachabilityStatusReachableViaWWAN:
[SVProgressHUD showInfoWithStatus:@"当前蜂窝移动网络"];
break;
default:
break;
}
}];
[mgr startMonitoring];
67、透明颜色不影响子视图透明度
[UIColor colorWithRed:<#(CGFloat)#> green:<#(CGFloat)#> blue:<#(CGFloat)#> alpha:<#(CGFloat)#>];
68、取图片某一点的颜色
if (point.x < 0 || point.y < 0) return nil;
CGImageRef imageRef = self.CGImage;
NSUInteger width = CGImageGetWidth(imageRef);
NSUInteger height = CGImageGetHeight(imageRef);
if (point.x >= width || point.y >= height) return nil;
unsigned char *rawData = malloc(height * width * 4);
if (!rawData) return nil;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
NSUInteger bytesPerPixel = 4;
NSUInteger bytesPerRow = bytesPerPixel * width;
NSUInteger bitsPerComponent = 8;
CGContextRef context = CGBitmapContextCreate(rawData,
width,
height,
bitsPerComponent,
bytesPerRow,
colorSpace,
kCGImageAlphaPremultipliedLast
| kCGBitmapByteOrder32Big);
if (!context) {
free(rawData);
return nil;
}
CGColorSpaceRelease(colorSpace);
CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);
CGContextRelease(context);
int byteIndex = (bytesPerRow * point.y) + point.x * bytesPerPixel;
CGFloat red = (rawData[byteIndex] * 1.0) / 255.0;
CGFloat green = (rawData[byteIndex + 1] * 1.0) / 255.0;
CGFloat blue = (rawData[byteIndex + 2] * 1.0) / 255.0;
CGFloat alpha = (rawData[byteIndex + 3] * 1.0) / 255.0;
UIColor *result = nil;
result = [UIColor colorWithRed:red green:green blue:blue alpha:alpha];
free(rawData);
return result;
69、判断该图片是否有透明度通道
- (BOOL)hasAlphaChannel
{
CGImageAlphaInfo alpha = CGImageGetAlphaInfo(self.CGImage);
return (alpha == kCGImageAlphaFirst ||
alpha == kCGImageAlphaLast ||
alpha == kCGImageAlphaPremultipliedFirst ||
alpha == kCGImageAlphaPremultipliedLast);
}
70、获得灰度图
+ (UIImage*)covertToGrayImageFromImage:(UIImage*)sourceImage
{
int width = sourceImage.size.width;
int height = sourceImage.size.height;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceGray();
CGContextRef context = CGBitmapContextCreate (nil,width,height,8,0,colorSpace,kCGImageAlphaNone);
CGColorSpaceRelease(colorSpace);
if (context == NULL) {
return nil;
}
CGContextDrawImage(context,CGRectMake(0, 0, width, height), sourceImage.CGImage);
CGImageRef contextRef = CGBitmapContextCreateImage(context);
UIImage *grayImage = [UIImage imageWithCGImage:contextRef];
CGContextRelease(context);
CGImageRelease(contextRef);
return grayImage;
}
71、根据bundle中的文件名读取图片
+ (UIImage *)imageWithFileName:(NSString *)name {
NSString *extension = @"png";
NSArray *components = [name componentsSeparatedByString:@"."];
if ([components count] >= 2) {
NSUInteger lastIndex = components.count - 1;
extension = [components objectAtIndex:lastIndex];
name = [name substringToIndex:(name.length-(extension.length+1))];
}
// 如果为Retina屏幕且存在对应图片,则返回Retina图片,否则查找普通图片
if ([UIScreen mainScreen].scale == 2.0) {
name = [name stringByAppendingString:@"@2x"];
NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:extension];
if (path != nil) {
return [UIImage imageWithContentsOfFile:path];
}
}
if ([UIScreen mainScreen].scale == 3.0) {
name = [name stringByAppendingString:@"@3x"];
NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:extension];
if (path != nil) {
return [UIImage imageWithContentsOfFile:path];
}
}
NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:extension];
if (path) {
return [UIImage imageWithContentsOfFile:path];
}
return nil;
}
72、合并两个图片
+ (UIImage*)mergeImage:(UIImage*)firstImage withImage:(UIImage*)secondImage {
CGImageRef firstImageRef = firstImage.CGImage;
CGFloat firstWidth = CGImageGetWidth(firstImageRef);
CGFloat firstHeight = CGImageGetHeight(firstImageRef);
CGImageRef secondImageRef = secondImage.CGImage;
CGFloat secondWidth = CGImageGetWidth(secondImageRef);
CGFloat secondHeight = CGImageGetHeight(secondImageRef);
CGSize mergedSize = CGSizeMake(MAX(firstWidth, secondWidth), MAX(firstHeight, secondHeight));
UIGraphicsBeginImageContext(mergedSize);
[firstImage drawInRect:CGRectMake(0, 0, firstWidth, firstHeight)];
[secondImage drawInRect:CGRectMake(0, 0, secondWidth, secondHeight)];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
73、根据bundle中的图片名创建imageview
+ (id)imageViewWithImageNamed:(NSString*)imageName
{
return [[UIImageView alloc] initWithImage:[UIImage imageNamed:imageName]];
}
74、为imageView添加倒影
CGRect frame = self.frame;
frame.origin.y += (frame.size.height + 1);
UIImageView *reflectionImageView = [[UIImageView alloc] initWithFrame:frame];
self.clipsToBounds = TRUE;
reflectionImageView.contentMode = self.contentMode;
[reflectionImageView setImage:self.image];
reflectionImageView.transform = CGAffineTransformMakeScale(1.0, -1.0);
CALayer *reflectionLayer = [reflectionImageView layer];
CAGradientLayer *gradientLayer = [CAGradientLayer layer];
gradientLayer.bounds = reflectionLayer.bounds;
gradientLayer.position = CGPointMake(reflectionLayer.bounds.size.width / 2, reflectionLayer.bounds.size.height * 0.5);
gradientLayer.colors = [NSArray arrayWithObjects:
(id)[[UIColor clearColor] CGColor],
(id)[[UIColor colorWithRed:1.0 green:1.0 blue:1.0 alpha:0.3] CGColor], nil];
gradientLayer.startPoint = CGPointMake(0.5,0.5);
gradientLayer.endPoint = CGPointMake(0.5,1.0);
reflectionLayer.mask = gradientLayer;
[self.superview addSubview:reflectionImageView];
75、画水印
// 画水印
- (void) setImage:(UIImage *)image withWaterMark:(UIImage *)mark inRect:(CGRect)rect
{
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 4.0)
{
UIGraphicsBeginImageContextWithOptions(self.frame.size, NO, 0.0);
}
//原图
[image drawInRect:self.bounds];
//水印图
[mark drawInRect:rect];
UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.image = newPic;
}
76、让label的文字内容显示在左上/右上/左下/右下/中心顶/中心底部
自定义UILabel
// 重写label的textRectForBounds方法
- (CGRect)textRectForBounds:(CGRect)bounds limitedToNumberOfLines:(NSInteger)numberOfLines {
CGRect rect = [super textRectForBounds:bounds limitedToNumberOfLines:numberOfLines];
switch (self.textAlignmentType) {
case WZBTextAlignmentTypeLeftTop: {
rect.origin = bounds.origin;
}
break;
case WZBTextAlignmentTypeRightTop: {
rect.origin = CGPointMake(CGRectGetMaxX(bounds) - rect.size.width, bounds.origin.y);
}
break;
case WZBTextAlignmentTypeLeftBottom: {
rect.origin = CGPointMake(bounds.origin.x, CGRectGetMaxY(bounds) - rect.size.height);
}
break;
case WZBTextAlignmentTypeRightBottom: {
rect.origin = CGPointMake(CGRectGetMaxX(bounds) - rect.size.width, CGRectGetMaxY(bounds) - rect.size.height);
}
break;
case WZBTextAlignmentTypeTopCenter: {
rect.origin = CGPointMake((CGRectGetWidth(bounds) - CGRectGetWidth(rect)) / 2, CGRectGetMaxY(bounds) - rect.origin.y);
}
break;
case WZBTextAlignmentTypeBottomCenter: {
rect.origin = CGPointMake((CGRectGetWidth(bounds) - CGRectGetWidth(rect)) / 2, CGRectGetMaxY(bounds) - CGRectGetMaxY(bounds) - rect.size.height);
}
break;
case WZBTextAlignmentTypeLeft: {
rect.origin = CGPointMake(0, rect.origin.y);
}
break;
case WZBTextAlignmentTypeRight: {
rect.origin = CGPointMake(rect.origin.x, 0);
}
break;
case WZBTextAlignmentTypeCenter: {
rect.origin = CGPointMake((CGRectGetWidth(bounds) - CGRectGetWidth(rect)) / 2, (CGRectGetHeight(bounds) - CGRectGetHeight(rect)) / 2);
}
break;
default:
break;
}
return rect;
}
- (void)drawTextInRect:(CGRect)rect {
CGRect textRect = [self textRectForBounds:rect limitedToNumberOfLines:self.numberOfLines];
[super drawTextInRect:textRect];
}
77、scrollView上的输入框,键盘挡住的问题
推荐用IQKeyboardManager这个框架!
手动解决如下
1、监听键盘弹出/消失的通知
2、在通知中加入代码:
NSDictionary* info = [aNotification userInfo];
CGRect keyPadFrame=[[UIApplication sharedApplication].keyWindow convertRect:[[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue] fromView:self.view];
CGSize kbSize =keyPadFrame.size;
CGRect activeRect=[self.view convertRect:activeField.frame fromView:activeField.superview];
CGRect aRect = self.view.bounds;
aRect.size.height -= (kbSize.height);
CGPoint origin = activeRect.origin;
origin.y -= backScrollView.contentOffset.y;
if (!CGRectContainsPoint(aRect, origin)) {
CGPoint scrollPoint = CGPointMake(0.0,CGRectGetMaxY(activeRect)-(aRect.size.height));
[backScrollView setContentOffset:scrollPoint animated:YES];
}
78、frame布局的cell动态高度
这种通常在你的模型中添加一个辅助属性cellHeight,在模型中重写这个属性的get方法,根据你的布局和模型中的其他属性值计算出总高度。最后在tableView:heightForRow方法中,根据indexPath找出对应的模型,返回这个高度即可。
79、AutoLayout布局的cell动态高度
// 1、设置tableView的属性
self.tableView.rowHeight = UITableViewAutomaticDimension;
self.tableView.estimatedRowHeight = 44.0; // 这个属性非0,估计cell高度
// 2、至上而下设置cell的约束,注意,上下左右最好都要顶到cell的四周
![](http://upload-images.jianshu.io/upload_images/1608265-8e19466b6e4ac956.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
80、使用performSelector:调用函数,内存泄漏问题
当我们在开发中使用[obj performSelector:NSSelectorFromString(@"aMethod")];这类方法时可能会收到一个警告"performSelector may cause a leak because its selector is unknown".
是因为编译器不清楚这个对象能不能相应这个方法,如果不能,则是不安全的,而且编译器也不清楚该怎么处理这个方法的返回值!
使用以下代码调用即可:
if (! obj) { return; }
SEL selector = NSSelectorFromString(@"aMethod");
IMP imp = [obj methodForSelector:selector];
void (*func)(id, SEL) = (void *)imp;
func(obj, selector);
或者:
SEL selector = NSSelectorFromString(@"aMethod");
((void (*)(id, SEL))[obj methodForSelector:selector])(obj, selector);
81、一个字符串是否包含另一个字符串
// 方法1
if ([str1 containsString:str2]) {
NSLog(@"str1包含str2");
} else {
NSLog(@"str1不包含str2");
}
// 方法2
if ([str1 rangeOfString: str2].location == NSNotFound) {
NSLog(@"str1不包含str2");
} else {
NSLog(@"str1包含str2");
}
82、cell去除选中效果
cell.selectionStyle = UITableViewCellSelectionStyleNone;
83、cell点按效果
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[tableView deselectRowAtIndexPath:indexPath animated:YES];
}
84、当删除一个从xib拖出来的属性时,一定记得把xib中对应的线也删掉,不然会报类似[<ViewController 0x7fea6ed05980> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key的crash
![](http://upload-images.jianshu.io/upload_images/1432270-a99e5b5fea0c8ad6.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
85、真机测试的时候报错:Could not launch "你的 App",process launch failed: Security
因为你的app没有上线,iOS9开始,需要手动信任Xcode生成的描述文件,打开手机设置->通用->描述文件->点击你的app的描述文件->点击信任
86、真机测试的时候报错:Could not find Developer Disk Image
这是因为你的设备系统版本大于Xcode能兼容的系统版本,比如你的设备是iOS10.3,而Xcode版本是8.2(Xcode8.2最大兼容iOS10.2),就会报这个错误。解决办法就是升级Xcode!
87、UITextView没有placeholder的问题?
网上有很多此类自定义控件,也可以参考下我写的一个UITextView分类 UITextView-WZB
88、移除字符串中的空格和换行
+ (NSString *)removeSpaceAndNewline:(NSString *)str {
NSString *temp = [str stringByReplacingOccurrencesOfString:@" " withString:@""];
temp = [temp stringByReplacingOccurrencesOfString:@"\r" withString:@""];
temp = [temp stringByReplacingOccurrencesOfString:@"\n" withString:@""];
return temp;
}
89、判断字符串中是否有空格
+ (BOOL)isBlank:(NSString *)str {
NSRange _range = [str rangeOfString:@" "];
if (_range.location != NSNotFound) {
//有空格
return YES;
} else {
//没有空格
return NO;
}
}
90、获取一个视频的第一帧图片
NSURL *url = [NSURL URLWithString:filepath];
AVURLAsset *asset1 = [[AVURLAsset alloc] initWithURL:url options:nil];
AVAssetImageGenerator *generate1 = [[AVAssetImageGenerator alloc] initWithAsset:asset1];
generate1.appliesPreferredTrackTransform = YES;
NSError *err = NULL;
CMTime time = CMTimeMake(1, 2);
CGImageRef oneRef = [generate1 copyCGImageAtTime:time actualTime:NULL error:&err];
UIImage *one = [[UIImage alloc] initWithCGImage:oneRef];
return one;
91、获取视频的时长
+ (NSInteger)getVideoTimeByUrlString:(NSString *)urlString {
NSURL *videoUrl = [NSURL URLWithString:urlString];
AVURLAsset *avUrl = [AVURLAsset assetWithURL:videoUrl];
CMTime time = [avUrl duration];
int seconds = ceil(time.value/time.timescale);
return seconds;
}
92、字符串是否为空
+ (BOOL)isEqualToNil:(NSString *)str {
return str.length <= 0 || [str isEqualToString:@""] || !str;
}
93、将app上传到App Store的时候通常会遇到这个问题
![](http://upload-images.jianshu.io/upload_images/1432270-8b75d749ac20c31e.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
很多人说这事苹果爸爸服务器问题,重复尝试几次,总会成功的!
但是经过尝试发现如果使用Application Loader上传成功率就非常高,所以还是推荐把ipa文件导出直接用Application Loader上传。
如果Application Loader也不行,需要检查下自己的网络,有时候vpn也会提高速度。
94、当tableView占不满一屏时,去除下边多余的单元格
self.tableView.tableHeaderView = [UIView new];
self.tableView.tableFooterView = [UIView new];
95、isKindOfClass和isMemberOfClass的区别
isKindOfClass可以判断某个对象是否属于某个类,或者这个类的子类。
isMemberOfClass更加精准,它只能判断这个对象类型是否为这个类(不能判断子类)
96、__block
当一个局部变量需要在block里改变时,需要在定义时加上__block修饰,具体请看官方文档http://developer.apple.com/library/ios/documentation/cocoa/Conceptual/Blocks/Articles/bxVariables.html#//apple_ref/doc/uid/TP40007502-CH6-SW6
97、-[ViewController aMethod:]: unrecognized selector sent to instance 0x7fe91e607fb0
这是一个经典错误,ViewController不能响应aMethod这个方法,错误原因可能viewController文件中没有实现aMethod这个方法
98、UITableView (<UITableView: 0x7ff19b027000; >) failed to obtain a cell from its dataSource (<ViewController: 0x7ff19a507520>)
这个错误原因是tableView的代理方法-tableView:cellForRowAtIndexPath:需要返回一个UITableViewCell,而你返回了一个nil。另外这个地方返回值不是UITableViewCell类型也会导致崩溃
99、约束如何做UIView动画?
1、把需要改的约束Constraint拖条线出来,成为属性
2、在需要动画的地方加入代码,改变此属性的constant属性
3、开始做UIView动画,动画里边调用layoutIfNeeded方法
@property (weak, nonatomic) IBOutlet NSLayoutConstraint *buttonTopConstraint;
self.buttonTopConstraint.constant = 100;
[UIView animateWithDuration:.5 animations:^{
[self.view layoutIfNeeded];
}];
100、从NSURL中拿到链接字符串
NSString *urlString = myURL.absoluteString;
101、将tableView滚动到顶部
[tableView setContentOffset:CGPointZero animated:YES];
或者
[tableView scrollRectToVisible:CGRectMake(0, 0, 1, 1) animated:YES];
102、如果用addTarget:action:forControlEvents:方法为一个button添加了很多点击事件,在某个时刻想一次删除怎么办?只需要调用下边这句代码
[youButton removeTarget:nil action:nil forControlEvents:UIControlEventAllEvents];
103、某个字体的高度
font.lineHeight;
104、删除某个view所有的子视图
[[someView subviews]
makeObjectsPerformSelector:@selector(removeFromSuperview)];
105、删除NSUserDefaults所有记录
//方法一
NSString *appDomain = [[NSBundle mainBundle] bundleIdentifier];
[[NSUserDefaults standardUserDefaults] removePersistentDomainForName:appDomain];
//方法二
- (void)resetDefaults {
NSUserDefaults * defs = [NSUserDefaults standardUserDefaults];
NSDictionary * dict = [defs dictionaryRepresentation];
for (id key in dict) {
[defs removeObjectForKey:key];
}
[defs synchronize];
}
// 方法三
[[NSUserDefaults standardUserDefaults] setPersistentDomain:[NSDictionary dictionary] forName:[[NSBundle mainBundle] bundleIdentifier]];
106、禁用系统滑动返回功能
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {self.navigationController.interactivePopGestureRecognizer.delegate = self;
}
}
- (void)viewWillDisappear:(BOOL)animated {
[super viewWillDisappear:animated];
if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {self.navigationController.interactivePopGestureRecognizer.delegate = nil;
}
}
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
return NO;
}
107、模拟器报错
![](http://upload-images.jianshu.io/upload_images/1432270-76da2a462b9f1eca.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
解决办法:
打开模拟器->Simulator->Reset Content and Settings...
如果不行,就重启试试!
108、自定义cell选中背景颜色
UIView *bgColorView = [[UIView alloc] init];
bgColorView.backgroundColor = [UIColor redColor];
[cell setSelectedBackgroundView:bgColorView];
109、UILabel设置内边距
子类化UILabel,重写drawTextInRect方法
- (void)drawTextInRect:(CGRect)rect {
// 边距,上左下右
UIEdgeInsets insets = {0, 5, 0, 5};
[super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];
}
110、UILabel设置文字描边
子类化UILabel,重写drawTextInRect方法
- (void)drawTextInRect:(CGRect)rect
{
CGContextRef c = UIGraphicsGetCurrentContext();
// 设置描边宽度
CGContextSetLineWidth(c, 1);
CGContextSetLineJoin(c, kCGLineJoinRound);
CGContextSetTextDrawingMode(c, kCGTextStroke);
// 描边颜色
self.textColor = [UIColor redColor];
[super drawTextInRect:rect];
// 文本颜色
self.textColor = [UIColor yellowColor];
CGContextSetTextDrawingMode(c, kCGTextFill);
[super drawTextInRect:rect];
}
111、使用模拟器截图
快捷键command + s
或者File->Save Screen Shot
112、scrollView滚动到最下边
CGPoint bottomOffset = CGPointMake(0, scrollView.contentSize.height - scrollView.bounds.size.height);
[scrollView setContentOffset:bottomOffset animated:YES];
113、UIView背景颜色渐变
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 100)];
[self.view addSubview:view];
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = view.bounds;
gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor blackColor] CGColor], (id)[[UIColor whiteColor] CGColor], nil];
[view.layer insertSublayer:gradient atIndex:0];
114、停止UIView动画
[yourView.layer removeAllAnimations]
115、为UIView某个角添加圆角
// 左上角和右下角添加圆角
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:view.bounds byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerBottomRight) cornerRadii:CGSizeMake(20, 20)];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = view.bounds;
maskLayer.path = maskPath.CGPath;
view.layer.mask = maskLayer;
116、删除Xcode Derived data缓存数据
依次点击Xcode -> Preferences -> location,然后点击 Derived data路径后到小箭头,删除这个文件夹下的数据就可以了,如图
Xcode Derived data
117、将一个view放置在其兄弟视图的最上面
[parentView bringSubviewToFront:yourView]
118、将一个view放置在其兄弟视图的最下面
[parentView sendSubviewToBack:yourView]
119、让手机震动一下
倒入框架
#import <AudioToolbox/AudioToolbox.h>
AudioServicesPlayAlertSound(kSystemSoundID_Vibrate);
或者
AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);
120、layoutSubviews方法什么时候调用?
1、init方法不会调用
2、addSubview方法等时候会调用
3、bounds改变的时候调用
4、scrollView滚动的时候会调用scrollView的layoutSubviews方法(所以不建议在scrollView的layoutSubviews方法中做复杂逻辑)
5、旋转设备的时候调用
6、子视图被移除的时候调用
参考请看:http://blog.logichigh.com/2011/03/16/when-does-layoutsubviews-get-called/
121、让UILabel在指定的地方换行
// 换行符为\n,在需要换行的地方加上这个符号即可,如
label.numberOfLines = 0;
label.text = @"此处\n换行";
122、摇一摇功能
1、打开摇一摇功能
[UIApplication sharedApplication].applicationSupportsShakeToEdit = YES;
2、让需要摇动的控制器成为第一响应者
[self becomeFirstResponder];
3、实现以下方法
// 开始摇动
- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event
// 取消摇动
- (void)motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event
// 摇动结束
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event
123、获取图片大小
CGFloat imageWidth = image.size.width;
CGFloat imageHeight = imageWidth * image.scale;
124、获取view的坐标在整个window上的位置
// v上的(0, 0)点在toView上的位置
CGPoint point = [v convertPoint:CGPointMake(0, 0) toView:[UIApplication sharedApplication].windows.lastObject];
或者
CGPoint point = [v.superview convertPoint:v.frame.origin toView:[UIApplication sharedApplication].windows.lastObject];
125、提交App Store审核程序限制
您的应用程序的未压缩大小必须小于4GB。每个Mach-O可执行文件(例如app_name.app/app_name)不能超过这些限制:
对于MinimumOSVersion小于7.0的应用程序:TEXT二进制文件中所有部分的总数最多为80 MB 。
对于MinimumOSVersion7.x到8.x的应用程序:TEXT对于二进制文件中每个体系结构片段的每个片段,最大为60 MB 。
对于MinimumOSVersion9.0或更高版本的应用程序:__TEXT二进制文件中所有部分的总数最多为500 MB 。参阅:iTunes Connect开发者指南
126、修改UISegmentedControl的字体大小
[segment setTitleTextAttributes:@{NSFontAttributeName : [UIFont systemFontOfSize:15.0f]} forState:UIControlStateNormal];
127、在非ViewController的地方弹出UIAlertController对话框
// 最好抽成一个分类
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"message" preferredStyle:UIAlertControllerStyleAlert];
//...
id rootViewController = [UIApplication sharedApplication].delegate.window.rootViewController;
if([rootViewController isKindOfClass:[UINavigationController class]])
{
rootViewController = ((UINavigationController *)rootViewController).viewControllers.firstObject;
}
if([rootViewController isKindOfClass:[UITabBarController class]])
{
rootViewController = ((UITabBarController *)rootViewController).selectedViewController;
}
[rootViewController presentViewController:alertController animated:YES completion:nil];
128、获取一个view所属的控制器
// view分类方法
- (UIViewController *)belongViewController {
for (UIView *next = [self superview]; next; next = next.superview) {
UIResponder* nextResponder = [next nextResponder];
if ([nextResponder isKindOfClass:[UIViewController class]]) {
return (UIViewController *)nextResponder;
}
}
return nil;
}
129、UIImage和base64互转
// view分类方法
- (NSString *)encodeToBase64String:(UIImage *)image {
return [UIImagePNGRepresentation(image) base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
}
- (UIImage *)decodeBase64ToImage:(NSString *)strEncodeData {
NSData *data = [[NSData alloc]initWithBase64EncodedString:strEncodeData options:NSDataBase64DecodingIgnoreUnknownCharacters];
return [UIImage imageWithData:data];
}
130、UIWebView设置背景透明
[webView setBackgroundColor:[UIColor clearColor]];
[webView setOpaque:NO];
131、判断NSDate是不是今天
NSDateComponents *otherDay = [[NSCalendar currentCalendar] components:NSCalendarUnitEra | NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay fromDate:aDate];
NSDateComponents *today = [[NSCalendar currentCalendar] components:NSCalendarUnitEra | NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay fromDate:[NSDate date]];
if([today day] == [otherDay day] &&
[today month] == [otherDay month] &&
[today year] == [otherDay year] &&
[today era] == [otherDay era]) {
// 是今天
}
132、设置tableView分割线颜色
[self.tableView setSeparatorColor:[UIColor myColor]];
133、设置屏幕方向
NSNumber *orientationTarget = [NSNumber numberWithInt:UIInterfaceOrientationLandscapeLeft];
[[UIDevice currentDevice] setValue:orientationTarget forKey:@"orientation"];
[UIViewController attemptRotationToDeviceOrientation];
134、比较两个颜色是否相等
- (BOOL)isEqualToColor:(UIColor *)otherColor {
CGColorSpaceRef colorSpaceRGB = CGColorSpaceCreateDeviceRGB();
UIColor *(^convertColorToRGBSpace)(UIColor*) = ^(UIColor *color) {
if (CGColorSpaceGetModel(CGColorGetColorSpace(color.CGColor)) == kCGColorSpaceModelMonochrome) {
const CGFloat *oldComponents = CGColorGetComponents(color.CGColor);
CGFloat components[4] = {oldComponents[0], oldComponents[0], oldComponents[0], oldComponents[1]};
CGColorRef colorRef = CGColorCreate( colorSpaceRGB, components );
UIColor *color = [UIColor colorWithCGColor:colorRef];
CGColorRelease(colorRef);
return color;
} else
return color;
};
UIColor *selfColor = convertColorToRGBSpace(self);
otherColor = convertColorToRGBSpace(otherColor);
CGColorSpaceRelease(colorSpaceRGB);
return [selfColor isEqual:otherColor];
}
135、tableViewCell分割线顶到头
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath {
[cell setSeparatorInset:UIEdgeInsetsZero];
[cell setLayoutMargins:UIEdgeInsetsZero];
cell.preservesSuperviewLayoutMargins = NO;
}
- (void)viewDidLayoutSubviews {
[self.tableView setSeparatorInset:UIEdgeInsetsZero];
[self.tableView setLayoutMargins:UIEdgeInsetsZero];
}
136、不让控制器的view随着控制器的xib拉伸或压缩
self.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
137、cocoaPods报错 : [!] Unable to add a source with url https://github.com/CocoaPods/Specs.git
named master-1
.
You can try adding it manually in ~/.cocoapods/repos
or via pod repo add
.
解决方法:这是因为电脑里安装了另外一个Xcode导致cocoapods找不到路径了
在终端执行 sudo xcode-select -switch /Applications/Xcode.app 即可
138、安装cocoapods的时候出现 ERROR: While executing gem ... (Errno::EPERM)
Operation not permitted - /usr/bin/pod
解决办法:直接在终端执行 sudo gem install -n /usr/local/bin cocoapods
139、在状态栏增加网络请求的菊花,类似safari加载网页的时候状态栏菊花
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
140、检查一个rect是否包含一个point
// point是否在rect内
BOOL isContains = CGRectContainsPoint(rect, point);
141、在指定的宽度下,让UILabel自动设置最佳font
label.adjustsFontSizeToFitWidth = YES;
142、将一个image保存在相册中
UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
或者
#import <Photos/Photos.h>
[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{
PHAssetChangeRequest *changeRequest = [PHAssetChangeRequest creationRequestForAssetFromImage:image];
changeRequest.creationDate = [NSDate date];
} completionHandler:^(BOOL success, NSError *error) {
if (success) {
NSLog(@"successfully saved");
}
else {
NSLog(@"error saving to photos: %@", error);
}
}];
143、修改cell.imageView的大小
UIImage *icon = [UIImage imageNamed:@""];
CGSize itemSize = CGSizeMake(30, 30);
UIGraphicsBeginImageContextWithOptions(itemSize, NO ,0.0);
CGRect imageRect = CGRectMake(0.0, 0.0, itemSize.width, itemSize.height);
[icon drawInRect:imageRect];
cell.imageView.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
144、为一个view添加虚线边框
CAShapeLayer *border = [CAShapeLayer layer];
border.strokeColor = [UIColor colorWithRed:67/255.0f green:37/255.0f blue:83/255.0f alpha:1].CGColor;
border.fillColor = nil;
border.lineDashPattern = @[@4, @2];
border.path = [UIBezierPath bezierPathWithRect:view.bounds].CGPath;
border.frame = view.bounds;
[view.layer addSublayer:border];
145、UITextView中打开或禁用复制,剪切,选择,全选等功能
// 继承UITextView重写这个方法
- (BOOL)canPerformAction:(SEL)action withSender:(id)sender
{
// 返回NO为禁用,YES为开启
// 粘贴
if (action == @selector(paste:)) return NO;
// 剪切
if (action == @selector(cut:)) return NO;
// 复制
if (action == @selector(copy:)) return NO;
// 选择
if (action == @selector(select:)) return NO;
// 选中全部
if (action == @selector(selectAll:)) return NO;
// 删除
if (action == @selector(delete:)) return NO;
// 分享
if (action == @selector(share)) return NO;
return [super canPerformAction:action withSender:sender];
}
1、设置UILabel行间距
NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString:label.text];
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
[style setLineSpacing:20];
[attrString addAttribute:NSParagraphStyleAttributeName value:style range:NSMakeRange(0, label.text.length)];
label.attributedText = attrString;
// 或者使用xib,看下gif图
Untitled.gif
2、当使用-performSelector:withObject:withObject:afterDelay:方法时,需要传入多参数问题
// 方法一、
// 把参数放进一个数组/字典,直接把数组/字典当成一个参数传过去,具体方法实现的地方再解析这个数组/字典
NSArray * array =
[NSArray arrayWithObjects: @"first", @"second", nil];
[self performSelector:@selector(fooFirstInput:) withObject: array afterDelay:15.0];
// 方法二、
// 使用NSInvocation
SEL aSelector = NSSelectorFromString(@"doSoming:argument2:");
NSInteger argument1 = 10;
NSString *argument2 = @"argument2";
if([self respondsToSelector:aSelector]) {
NSInvocation *inv = [NSInvocation invocationWithMethodSignature:[self methodSignatureForSelector:aSelector]];
[inv setSelector:aSelector];
[inv setTarget:self];
[inv setArgument:&(argument1) atIndex:2];
[inv setArgument:&(argument2) atIndex:3];
[inv performSelector:@selector(invoke) withObject:nil afterDelay:15.0];
}
3、UILabel显示不同颜色字体
NSMutableAttributedString * string = [[NSMutableAttributedString alloc] initWithString:label.text];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0,5)];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:NSMakeRange(5,6)];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:NSMakeRange(11,5)];
label.attributedText = string;
4、比较两个CGRect/CGSize/CGPoint是否相等
if (CGRectEqualToRect(rect1, rect2)) { // 两个区域相等
// do some
}
if (CGPointEqualToPoint(point1, point2)) { // 两个点相等
// do some
}
if (CGSizeEqualToSize(size1, size2)) { // 两个size相等
// do some
}
5、比较两个NSDate相差多少小时
NSDate* date1 = someDate;
NSDate* date2 = someOtherDate;
NSTimeInterval distanceBetweenDates = [date1 timeIntervalSinceDate:date2];
double secondsInAnHour = 3600;
// 除以3600是把秒化成小时,除以60得到结果为相差的分钟数
NSInteger hoursBetweenDates = distanceBetweenDates / secondsInAnHour;
6、每个cell之间增加间距
// 方法一,每个分区只显示一行cell,分区头当作你想要的间距(注意,从数据源数组中取值的时候需要用indexPath.section而不是indexPath.row)
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return yourArry.count;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return 1;
}
-(CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
return cellSpacingHeight;
}
// 方法二,在cell的contentView上加个稍微低一点的view,cell上原本的内容放在你的view上,而不是contentView上,这样能伪造出一个间距来。
// 方法三,自定义cell,重写setFrame:方法
- (void)setFrame:(CGRect)frame
{
frame.size.height -= 20;
[super setFrame:frame];
}
7、播放一张张连续的图片
// 加入现在有三张图片分别为animate_1、animate_2、animate_3
// 方法一
imageView.animationImages = @[[UIImage imageNamed:@"animate_1"], [UIImage imageNamed:@"animate_2"], [UIImage imageNamed:@"animate_3"]];
imageView.animationDuration = 1.0;
// 方法二
imageView.image = [UIImage animatedImageNamed:@"animate_" duration:1.0];
// 方法二解释下,这个方法会加载animate_为前缀的,后边0-1024,也就是animate_0、animate_1一直到animate_1024
8、加载gif图片
推荐使用这个框架 FLAnimatedImage
9、防止离屏渲染为image添加圆角
// image分类
- (UIImage *)circleImage
{
// NO代表透明
UIGraphicsBeginImageContextWithOptions(self.size, NO, 1);
// 获得上下文
CGContextRef ctx = UIGraphicsGetCurrentContext();
// 添加一个圆
CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);
// 方形变圆形
CGContextAddEllipseInRect(ctx, rect);
// 裁剪
CGContextClip(ctx);
// 将图片画上去
[self drawInRect:rect];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
10、查看系统所有字体
// 打印字体
for (id familyName in [UIFont familyNames]) {
NSLog(@"%@", familyName);
for (id fontName in [UIFont fontNamesForFamilyName:familyName]) NSLog(@" %@", fontName);
}
// 也可以进入这个网址查看 http://iosfonts.com/
11、获取随机数
NSInteger i = arc4random();
12、获取随机数小数(0-1之间)
#define ARC4RANDOM_MAX 0x100000000
double val = ((double)arc4random() / ARC4RANDOM_MAX);
13、AVPlayer视频播放完成的通知监听
[[NSNotificationCenter defaultCenter]
addObserver:self
selector:@selector(videoPlayEnd)
name:AVPlayerItemDidPlayToEndTimeNotification
object:nil];
14、判断两个rect是否有交叉
if (CGRectIntersectsRect(rect1, rect2)) {
}
15、判断一个字符串是否为数字
NSCharacterSet *notDigits = [[NSCharacterSet decimalDigitCharacterSet] invertedSet];
if ([str rangeOfCharacterFromSet:notDigits].location == NSNotFound)
{
// 是数字
} else
{
// 不是数字
}
16、将一个view保存为pdf格式
- (void)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename
{
NSMutableData *pdfData = [NSMutableData data];
UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);
UIGraphicsBeginPDFPage();
CGContextRef pdfContext = UIGraphicsGetCurrentContext();
[aView.layer renderInContext:pdfContext];
UIGraphicsEndPDFContext();
NSArray* documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);
NSString* documentDirectory = [documentDirectories objectAtIndex:0];
NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename];
[pdfData writeToFile:documentDirectoryFilename atomically:YES];
NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);
}
17、让一个view在父视图中心
child.center = [parent convertPoint:parent.center fromView:parent.superview];
18、获取当前导航控制器下前一个控制器
- (UIViewController *)backViewController
{
NSInteger myIndex = [self.navigationController.viewControllers indexOfObject:self];
if ( myIndex != 0 && myIndex != NSNotFound ) {
return [self.navigationController.viewControllers objectAtIndex:myIndex-1];
} else {
return nil;
}
}
19、保存UIImage到本地
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"Image.png"];
[UIImagePNGRepresentation(image) writeToFile:filePath atomically:YES];
20、键盘上方增加工具栏
UIToolbar *keyboardDoneButtonView = [[UIToolbar alloc] init];
[keyboardDoneButtonView sizeToFit];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithTitle:@"Done"
style:UIBarButtonItemStyleBordered target:self
action:@selector(doneClicked:)];
[keyboardDoneButtonView setItems:[NSArray arrayWithObjects:doneButton, nil]];
txtField.inputAccessoryView = keyboardDoneButtonView;
21、copy一个view
因为UIView没有实现copy协议,因此找不到copyWithZone方法,使用copy的时候导致崩溃
但是我们可以通过归档再解档实现copy,这相当于对视图进行了一次深拷贝,代码如下
id copyOfView =
[NSKeyedUnarchiver unarchiveObjectWithData:[NSKeyedArchiver archivedDataWithRootObject:originalView]];
22、在image上绘制文字并生成新的image
UIFont *font = [UIFont boldSystemFontOfSize:12];
UIGraphicsBeginImageContext(image.size);
[image drawInRect:CGRectMake(0,0,image.size.width,image.size.height)];
CGRect rect = CGRectMake(point.x, point.y, image.size.width, image.size.height);
[[UIColor whiteColor] set];
[text drawInRect:CGRectIntegral(rect) withFont:font];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
23、判断一个view是否为另一个view的子视图
// 如果myView是self.view本身,也会返回yes
BOOL isSubView = [myView isDescendantOfView:self.view];
24、判断一个字符串是否包含另一个字符串
// 方法一、这种方法只适用于iOS8之后,如果是配iOS8之前用方法二
if ([str containsString:otherStr]) NSLog(@"包含");
// 方法二
NSRange range = [str rangeOfString:otherStr];
if (range.location != NSNotFound) NSLog(@"包含");
25、UICollectionView自动滚动到某行
// 重写viewDidLayoutSubviews方法
-(void)viewDidLayoutSubviews {
[super viewDidLayoutSubviews];
[self.collectionView scrollToItemAtIndexPath:indexPath atScrollPosition:UICollectionViewScrollPositionCenteredVertically animated:NO];
}
26、修改系统UIAlertController
// 但是据说这种方法会被App Store拒绝(慎用!)
UIAlertController *alertVC = [UIAlertController alertControllerWithTitle:@"" message:@"" preferredStyle:UIAlertControllerStyleActionSheet];
NSMutableAttributedString *hogan = [[NSMutableAttributedString alloc] initWithString:@"我是一个大文本"];
[hogan addAttribute:NSFontAttributeName
value:[UIFont systemFontOfSize:30]
range:NSMakeRange(4, 1)];
[hogan addAttribute:NSForegroundColorAttributeName
value:[UIColor redColor]
range:NSMakeRange(4, 1)];
[alertVC setValue:hogan forKey:@"attributedTitle"];
UIAlertAction *button = [UIAlertAction actionWithTitle:@"Label text" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action){ }];
UIImage *accessoryImage = [UIImage imageNamed:@"1"];
[button setValue:accessoryImage forKey:@"image"];
[alertVC addAction:button];
[self presentViewController:alertVC animated:YES completion:nil];
27、判断某一行的cell是否已经显示
CGRect cellRect = [tableView rectForRowAtIndexPath:indexPath];
BOOL completelyVisible = CGRectContainsRect(tableView.bounds, cellRect);
28、让导航控制器pop回指定的控制器
NSMutableArray *allViewControllers = [NSMutableArray arrayWithArray:[self.navigationController viewControllers]];
for (UIViewController *aViewController in allViewControllers) {
if ([aViewController isKindOfClass:[RequiredViewController class]]) {
[self.navigationController popToViewController:aViewController animated:NO];
}
}
29、动画修改label上的文字
// 方法一
CATransition *animation = [CATransition animation];
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
animation.type = kCATransitionFade;
animation.duration = 0.75;
[self.label.layer addAnimation:animation forKey:@"kCATransitionFade"];
self.label.text = @"New";
// 方法二
[UIView transitionWithView:self.label
duration:0.25f
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^{
self.label.text = @"Well done!";
} completion:nil];
// 方法三
[UIView animateWithDuration:1.0
animations:^{
self.label.alpha = 0.0f;
self.label.text = @"newText";
self.label.alpha = 1.0f;
}];
30、判断字典中是否包含某个key值
if ([dic objectForKey:@"yourKey"]) {
NSLog(@"有这个值");
} else {
NSLog(@"没有这个值");
}
31、获取屏幕方向
UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;
if(orientation == 0) //Default orientation
//默认
else if(orientation == UIInterfaceOrientationPortrait)
//竖屏
else if(orientation == UIInterfaceOrientationLandscapeLeft)
// 左横屏
else if(orientation == UIInterfaceOrientationLandscapeRight)
//右横屏
32、设置UIImage的透明度
// 方法一、添加UIImage分类
- (UIImage *)imageByApplyingAlpha:(CGFloat) alpha {
UIGraphicsBeginImageContextWithOptions(self.size, NO, 0.0f);
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGRect area = CGRectMake(0, 0, self.size.width, self.size.height);
CGContextScaleCTM(ctx, 1, -1);
CGContextTranslateCTM(ctx, 0, -area.size.height);
CGContextSetBlendMode(ctx, kCGBlendModeMultiply);
CGContextSetAlpha(ctx, alpha);
CGContextDrawImage(ctx, area, self.CGImage);
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
// 方法二、如果没有奇葩需求,干脆用UIImageView设置透明度
UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageWithName:@"yourImage"]];
imageView.alpha = 0.5;
33、Attempt to mutate immutable object with insertString:atIndex:
这个错是因为你拿字符串调用insertString:atIndex:方法的时候,调用对象不是NSMutableString,应该先转成这个类型再调用
34、UIWebView添加单击手势不响应
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(webViewClick)];
tap.delegate = self;
[_webView addGestureRecognizer:tap];
// 因为webView本身有一个单击手势,所以再添加会造成手势冲突,从而不响应。需要绑定手势代理,并实现下边的代理方法
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
return YES;
}
35、获取手机RAM容量
// 需要导入#import <mach/mach.h>
mach_port_t host_port;
mach_msg_type_number_t host_size;
vm_size_t pagesize;
host_port = mach_host_self();
host_size = sizeof(vm_statistics_data_t) / sizeof(integer_t);
host_page_size(host_port, &pagesize);
vm_statistics_data_t vm_stat;
if (host_statistics(host_port, HOST_VM_INFO, (host_info_t)&vm_stat, &host_size) != KERN_SUCCESS) {
NSLog(@"Failed to fetch vm statistics");
}
/* Stats in bytes */
natural_t mem_used = (vm_stat.active_count +
vm_stat.inactive_count +
vm_stat.wire_count) * pagesize;
natural_t mem_free = vm_stat.free_count * pagesize;
natural_t mem_total = mem_used + mem_free;
NSLog(@"已用: %u 可用: %u 总共: %u", mem_used, mem_free, mem_total);
36、地图上两个点之间的实际距离
// 需要导入#import <CoreLocation/CoreLocation.h>
CLLocation *locA = [[CLLocation alloc] initWithLatitude:34 longitude:113];
CLLocation *locB = [[CLLocation alloc] initWithLatitude:31.05 longitude:121.76];
// CLLocationDistance求出的单位为米
CLLocationDistance distance = [locA distanceFromLocation:locB];
37、在应用中打开设置的某个界面
// 打开设置->通用
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"prefs:root=General"]];
// 以下是设置其他界面
prefs:root=General&path=About
prefs:root=General&path=ACCESSIBILITY
prefs:root=AIRPLANE_MODE
prefs:root=General&path=AUTOLOCK
prefs:root=General&path=USAGE/CELLULAR_USAGE
prefs:root=Brightness
prefs:root=Bluetooth
prefs:root=General&path=DATE_AND_TIME
prefs:root=FACETIME
prefs:root=General
prefs:root=General&path=Keyboard
prefs:root=CASTLE
prefs:root=CASTLE&path=STORAGE_AND_BACKUP
prefs:root=General&path=INTERNATIONAL
prefs:root=LOCATION_SERVICES
prefs:root=ACCOUNT_SETTINGS
prefs:root=MUSIC
prefs:root=MUSIC&path=EQ
prefs:root=MUSIC&path=VolumeLimit
prefs:root=General&path=Network
prefs:root=NIKE_PLUS_IPOD
prefs:root=NOTES
prefs:root=NOTIFICATIONS_ID
prefs:root=Phone
prefs:root=Photos
prefs:root=General&path=ManagedConfigurationList
prefs:root=General&path=Reset
prefs:root=Sounds&path=Ringtone
prefs:root=Safari
prefs:root=General&path=Assistant
prefs:root=Sounds
prefs:root=General&path=SOFTWARE_UPDATE_LINK
prefs:root=STORE
prefs:root=TWITTER
prefs:root=FACEBOOK
prefs:root=General&path=USAGE prefs:root=VIDEO
prefs:root=General&path=Network/VPN
prefs:root=Wallpaper
prefs:root=WIFI
prefs:root=INTERNET_TETHERING
prefs:root=Phone&path=Blocked
prefs:root=DO_NOT_DISTURB
38、在UITextView中显示html文本
UITextView *textView = [[UITextView alloc] initWithFrame:CGRectMake(20, 30, 100, 199)];
textView.backgroundColor = [UIColor redColor];
[self.view addSubview:textView];
NSString *htmlString = @"<h1>Header</h1><h2>Subheader</h2><p>Some <em>text</em></p>![](http://blogs.babble.com/famecrawler/files/2010/11/mickey_mouse-1097.jpg)";
NSAttributedString *attributedString = [[NSAttributedString alloc] initWithData: [htmlString dataUsingEncoding:NSUnicodeStringEncoding] options: @{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType } documentAttributes: nil error: nil];
textView.attributedText = attributedString;
39、监听scrollView是否滚动到了顶部/底部
-(void)scrollViewDidScroll: (UIScrollView*)scrollView
{
float scrollViewHeight = scrollView.frame.size.height;
float scrollContentSizeHeight = scrollView.contentSize.height;
float scrollOffset = scrollView.contentOffset.y;
if (scrollOffset == 0)
{
// 滚动到了顶部
}
else if (scrollOffset + scrollViewHeight == scrollContentSizeHeight)
{
// 滚动到了底部
}
}
40、UISlider增量/减量为固定值(假如为5)
- (void)setupSlider
{
UISlider *slider = [[UISlider alloc] init];
[self.view addSubview:slider];
[slider addTarget:self action:@selector(sliderAction:) forControlEvents:UIControlEventValueChanged];
slider.maximumValue = 100;
slider.minimumValue = 0;
slider.frame = CGRectMake(200, 20, 100, 30);
}
- (void)sliderAction:(UISlider *)slider
{
[slider setValue:((int)((slider.value + 2.5) / 5) * 5) animated:NO];
}
41、选中textField或者textView所有文本(我这里以textView为例)
[self.textView setSelectedTextRange:[self.textView textRangeFromPosition:self.textView.beginningOfDocument toPosition:self.textView.endOfDocument]]
42、从导航控制器中删除某个控制器
// 方法一、知道这个控制器所处的导航控制器下标
NSMutableArray *navigationArray = [[NSMutableArray alloc] initWithArray: self.navigationController.viewControllers];
[navigationArray removeObjectAtIndex: 2];
self.navigationController.viewControllers = navigationArray;
// 方法二、知道具体是哪个控制器
NSArray* tempVCA = [self.navigationController viewControllers];
for(UIViewController *tempVC in tempVCA)
{
if([tempVC isKindOfClass:[urViewControllerClass class]])
{
[tempVC removeFromParentViewController];
}
}
43、隐藏UITextView/UITextField光标
textField.tintColor = [UIColor clearColor];
44、当UITextView/UITextField中没有文字时,禁用回车键
textField.enablesReturnKeyAutomatically = YES;
45、字符串encode编码(编码url字符串不成功的问题)
// 我们一般用这个方法处理stringByAddingPercentEscapesUsingEncoding但是这个方法好想不会处理/和&这种特殊符号,这种情况就需要用下边这个方法处理
@implementation NSString (NSString_Extended)
- (NSString *)urlencode {
NSMutableString *output = [NSMutableString string];
const unsigned char *source = (const unsigned char *)[self UTF8String];
int sourceLen = strlen((const char *)source);
for (int i = 0; i < sourceLen; ++i) {
const unsigned char thisChar = source[i];
if (thisChar == ' '){
[output appendString:@"+"];
} else if (thisChar == '.' || thisChar == '-' || thisChar == '_' || thisChar == '~' ||
(thisChar >= 'a' && thisChar <= 'z') ||
(thisChar >= 'A' && thisChar <= 'Z') ||
(thisChar >= '0' && thisChar <= '9')) {
[output appendFormat:@"%c", thisChar];
} else {
[output appendFormat:@"%%%02X", thisChar];
}
}
return output;
}
46、计算UILabel上某段文字的frame
@implementation UILabel (TextRect)
- (CGRect)boundingRectForCharacterRange:(NSRange)range
{
NSTextStorage *textStorage = [[NSTextStorage alloc] initWithAttributedString:[self attributedText]];
NSLayoutManager *layoutManager = [[NSLayoutManager alloc] init];
[textStorage addLayoutManager:layoutManager];
NSTextContainer *textContainer = [[NSTextContainer alloc] initWithSize:[self bounds].size];
textContainer.lineFragmentPadding = 0;
[layoutManager addTextContainer:textContainer];
NSRange glyphRange;
[layoutManager characterRangeForGlyphRange:range actualGlyphRange:&glyphRange];
return [layoutManager boundingRectForGlyphRange:glyphRange inTextContainer:textContainer];
}
47、获取随机UUID
NSString *result;
if([[[UIDevice currentDevice] systemVersion] floatValue] > 6.0)
{
result = [[NSUUID UUID] UUIDString];
}
else
{
CFUUIDRef uuidRef = CFUUIDCreate(NULL);
CFStringRef uuid = CFUUIDCreateString(NULL, uuidRef);
CFRelease(uuidRef);
result = (__bridge_transfer NSString *)uuid;
}
48、仿苹果抖动动画
#define RADIANS(degrees) (((degrees) * M_PI) / 180.0)
- (void)startAnimate {
view.transform = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(-5));
[UIView animateWithDuration:0.25 delay:0.0 options:(UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionRepeat | UIViewAnimationOptionAutoreverse) animations:^ {
view.transform = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(5));
} completion:nil];
}
- (void)stopAnimate {
[UIView animateWithDuration:0.25 delay:0.0 options:(UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionBeginFromCurrentState | UIViewAnimationOptionCurveLinear) animations:^ {
view.transform = CGAffineTransformIdentity;
} completion:nil];
}
49、修改UISearBar内部背景颜色
UITextField *textField = [_searchBar valueForKey:@"_searchField"];
textField.backgroundColor = [UIColor redColor];
50、UITextView滚动到顶部
// 方法一
[self.textView scrollRangeToVisible:NSMakeRange(0, 0)];
// 方法二
[self.textView setContentOffset:CGPointZero animated:YES];
51、通知监听APP生命周期
UIApplicationDidEnterBackgroundNotification 应用程序进入后台
UIApplicationWillEnterForegroundNotification 应用程序将要进入前台
UIApplicationDidFinishLaunchingNotification 应用程序完成启动
UIApplicationDidFinishLaunchingNotification 应用程序由挂起变的活跃
UIApplicationWillResignActiveNotification 应用程序挂起(有电话进来或者锁屏)
UIApplicationDidReceiveMemoryWarningNotification 应用程序收到内存警告
UIApplicationDidReceiveMemoryWarningNotification 应用程序终止(后台杀死、手机关机等)
UIApplicationSignificantTimeChangeNotification 当有重大时间改变(凌晨0点,设备时间被修改,时区改变等)
UIApplicationWillChangeStatusBarOrientationNotification 设备方向将要改变
UIApplicationDidChangeStatusBarOrientationNotification 设备方向改变
UIApplicationWillChangeStatusBarFrameNotification 设备状态栏frame将要改变
UIApplicationDidChangeStatusBarFrameNotification 设备状态栏frame改变
UIApplicationBackgroundRefreshStatusDidChangeNotification 应用程序在后台下载内容的状态发生变化
UIApplicationProtectedDataWillBecomeUnavailable 本地受保护的文件被锁定,无法访问
UIApplicationProtectedDataWillBecomeUnavailable 本地受保护的文件可用了
52、触摸事件类型
UIControlEventTouchCancel 取消控件当前触发的事件
UIControlEventTouchDown 点按下去的事件
UIControlEventTouchDownRepeat 重复的触动事件
UIControlEventTouchDragEnter 手指被拖动到控件的边界的事件
UIControlEventTouchDragExit 一个手指从控件内拖到外界的事件
UIControlEventTouchDragInside 手指在控件的边界内拖动的事件
UIControlEventTouchDragOutside 手指在控件边界之外被拖动的事件
UIControlEventTouchUpInside 手指处于控制范围内的触摸事件
UIControlEventTouchUpOutside 手指超出控制范围的控制中的触摸事件
53、UITextField文字周围增加边距
// 子类化UITextField,增加insert属性
@interface WZBTextField : UITextField
@property (nonatomic, assign) UIEdgeInsets insets;
@end
// 在.m文件重写下列方法
- (CGRect)textRectForBounds:(CGRect)bounds {
CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets);
if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeUnlessEditing) {
return [self adjustRectWithWidthRightView:paddedRect];
}
return paddedRect;
}
- (CGRect)placeholderRectForBounds:(CGRect)bounds {
CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets);
if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeUnlessEditing) {
return [self adjustRectWithWidthRightView:paddedRect];
}
return paddedRect;
}
- (CGRect)editingRectForBounds:(CGRect)bounds {
CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets);
if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeWhileEditing) {
return [self adjustRectWithWidthRightView:paddedRect];
}
return paddedRect;
}
- (CGRect)adjustRectWithWidthRightView:(CGRect)bounds {
CGRect paddedRect = bounds;
paddedRect.size.width -= CGRectGetWidth(self.rightView.frame);
return paddedRect;
}
54、监听UISlider拖动状态
// 添加事件
[slider addTarget:self action:@selector(sliderValurChanged:forEvent:) forControlEvents:UIControlEventValueChanged];
// 实现方法
- (void)sliderValurChanged:(UISlider*)slider forEvent:(UIEvent*)event {
UITouch *touchEvent = [[event allTouches] anyObject];
switch (touchEvent.phase) {
case UITouchPhaseBegan:
NSLog(@"开始拖动");
break;
case UITouchPhaseMoved:
NSLog(@"正在拖动");
break;
case UITouchPhaseEnded:
NSLog(@"结束拖动");
break;
default:
break;
}
}
55、设置UITextField光标位置
// textField需要设置的textField,index要设置的光标位置
- (void)cursorLocation:(UITextField *)textField index:(NSInteger)index
{
NSRange range = NSMakeRange(index, 0);
UITextPosition *start = [textField positionFromPosition:[textField beginningOfDocument] offset:range.location];
UITextPosition *end = [textField positionFromPosition:start offset:range.length];
[textField setSelectedTextRange:[textField textRangeFromPosition:start toPosition:end]];
}
56、去除webView底部黑色
[webView setBackgroundColor:[UIColor clearColor]];
[webView setOpaque:NO];
for (UIView *v1 in [webView subviews])
{
if ([v1 isKindOfClass:[UIScrollView class]])
{
for (UIView *v2 in v1.subviews)
{
if ([v2 isKindOfClass:[UIImageView class]])
{
v2.hidden = YES;
}
}
}
}
57、获取collectionViewCell在屏幕中的frame
UICollectionViewLayoutAttributes *attributes = [collectionView layoutAttributesForItemAtIndexPath:indexPath];
CGRect cellRect = attributes.frame;
CGRect cellFrameInSuperview = [collectionView convertRect:cellRect toView:[cv superview]];
58、比较两个UIImage是否相等
- (BOOL)image:(UIImage *)image1 isEqualTo:(UIImage *)image2
{
NSData *data1 = UIImagePNGRepresentation(image1);
NSData *data2 = UIImagePNGRepresentation(image2);
return [data1 isEqual:data2];
}
59、解决当UIScrollView上有UIButton的时候,触摸到button滑动不了的问题
// 子类化UIScrollView,并重写以下方法
- (instancetype)initWithFrame:(CGRect)frame {
if (self = [super initWithFrame:frame]) {
self.delaysContentTouches = NO;
}
return self;
}
- (BOOL)touchesShouldCancelInContentView:(UIView *)view {
if ([view isKindOfClass:UIButton.class]) {
return YES;
}
return [super touchesShouldCancelInContentView:view];
}
60、UITextView中的文字添加阴影效果
- (void)setTextLayer:(UITextView *)textView color:(UIColor *)color
{
CALayer *textLayer = ((CALayer *)[textView.layer.sublayers objectAtIndex:0]);
textLayer.shadowColor = color.CGColor;
textLayer.shadowOffset = CGSizeMake(0.0f, 1.0f);
textLayer.shadowOpacity = 1.0f;
textLayer.shadowRadius = 1.0f;
}
61、MD5加密
+ (NSString *)md5:(NSString *)str
{
const char *concat_str = [str UTF8String];
unsigned char result[CC_MD5_DIGEST_LENGTH];
CC_MD5(concat_str, (unsigned int)strlen(concat_str), result);
NSMutableString *hash = [NSMutableString string];
for (int i =0; i <16; i++){
[hash appendFormat:@"%02X", result[i]];
}
return [hash uppercaseString];
}
62、base64加密
@interface NSData (Base64)
/**
* @brief 字符串base64后转data
*/
+ (NSData *)dataWithBase64EncodedString:(NSString *)string
{
if (![string length]) return nil;
NSData *decoded = nil;
#if __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_9 || __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_7_0
if (![NSData instancesRespondToSelector:@selector(initWithBase64EncodedString:options:)])
{
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
decoded = [[self alloc] initWithBase64Encoding:[string stringByReplacingOccurrencesOfString:@"[^A-Za-z0-9+/=]" withString:@"" options:NSRegularExpressionSearch range:NSMakeRange(0, [string length])]];
#pragma clang diagnostic pop
}
else
#endif
{
decoded = [[self alloc] initWithBase64EncodedString:string options:NSDataBase64DecodingIgnoreUnknownCharacters];
}
return [decoded length]? decoded: nil;
}
/**
* @brief NSData转string
* @param wrapWidth 换行长度 76 64
*/
- (NSString *)base64EncodedStringWithWrapWidth:(NSUInteger)wrapWidth
{
if (![self length]) return nil;
NSString *encoded = nil;
#if __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_9 || __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_7_0
if (![NSData instancesRespondToSelector:@selector(base64EncodedStringWithOptions:)])
{
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
encoded = [self base64Encoding];
#pragma clang diagnostic pop
}
else
#endif
{
switch (wrapWidth)
{
case 64:
{
return [self base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
}
case 76:
{
return [self base64EncodedStringWithOptions:NSDataBase64Encoding76CharacterLineLength];
}
default:
{
encoded = [self base64EncodedStringWithOptions:(NSDataBase64EncodingOptions)0];
}
}
}
if (!wrapWidth || wrapWidth >= [encoded length])
{
return encoded;
}
wrapWidth = (wrapWidth / 4) * 4;
NSMutableString *result = [NSMutableString string];
for (NSUInteger i = 0; i < [encoded length]; i+= wrapWidth)
{
if (i + wrapWidth >= [encoded length])
{
[result appendString:[encoded substringFromIndex:i]];
break;
}
[result appendString:[encoded substringWithRange:NSMakeRange(i, wrapWidth)]];
[result appendString:@"\r\n"];
}
return result;
}
/**
* @brief NSData转string 换行长度默认64
*/
- (NSString *)base64EncodedString
{
return [self base64EncodedStringWithWrapWidth:0];
}
63、AES加密
#import <CommonCrypto/CommonCryptor.h>
@interface NSData (AES)
/**
* 利用AES加密数据
*/
- (NSData*)encryptedWithAESUsingKey:(NSString*)key andIV:(NSData*)iv {
NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];
size_t dataMoved;
NSMutableData *encryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSizeAES128];
CCCryptorStatus status = CCCrypt(kCCEncrypt,kCCAlgorithmAES128,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,encryptedData.mutableBytes, encryptedData.length,&dataMoved);
if (status == kCCSuccess) {
encryptedData.length = dataMoved;
return encryptedData;
}
return nil;
}
/**
* @brief 利用AES解密据
*/
- (NSData*)decryptedWithAESUsingKey:(NSString*)key andIV:(NSData*)iv {
NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];
size_t dataMoved;
NSMutableData *decryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSizeAES128];
CCCryptorStatus result = CCCrypt(kCCDecrypt,kCCAlgorithmAES128,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,decryptedData.mutableBytes, decryptedData.length,&dataMoved);
if (result == kCCSuccess) {
decryptedData.length = dataMoved;
return decryptedData;
}
return nil;
}
64、3DES加密
#import <CommonCrypto/CommonCryptor.h>
@interface NSData (3DES)
/**
* 利用3DES加密数据
*/
- (NSData*)encryptedWith3DESUsingKey:(NSString*)key andIV:(NSData*)iv {
NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];
size_t dataMoved;
NSMutableData *encryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSize3DES];
CCCryptorStatus result = CCCrypt(kCCEncrypt,kCCAlgorithm3DES,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,encryptedData.mutableBytes,encryptedData.length,&dataMoved);
if (result == kCCSuccess) {
encryptedData.length = dataMoved;
return encryptedData;
}
return nil;
}
/**
* @brief 利用3DES解密数据
*/
- (NSData*)decryptedWith3DESUsingKey:(NSString*)key andIV:(NSData*)iv {
NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];
size_t dataMoved;
NSMutableData *decryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSize3DES];
CCCryptorStatus result = CCCrypt(kCCDecrypt,kCCAlgorithm3DES,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,decryptedData.mutableBytes,decryptedData.length,&dataMoved);
if (result == kCCSuccess) {
decryptedData.length = dataMoved;
return decryptedData;
}
return nil;
}
65、单个页面多个网络请求的情况,需要监听所有网络请求结束后刷新UI
dispatch_group_t group = dispatch_group_create();
dispatch_queue_t serialQueue = dispatch_queue_create("com.wzb.test.www", DISPATCH_QUEUE_SERIAL);
dispatch_group_enter(group);
dispatch_group_async(group, serialQueue, ^{
// 网络请求一
[WebClick getDataSuccess:^(ResponseModel *model) {
dispatch_group_leave(group);
} failure:^(NSString *err) {
dispatch_group_leave(group);
}];
});
dispatch_group_enter(group);
dispatch_group_async(group, serialQueue, ^{
// 网络请求二
[WebClick getDataSuccess:getBigTypeRM onSuccess:^(ResponseModel *model) {
dispatch_group_leave(group);
} failure:^(NSString *errorString) {
dispatch_group_leave(group);
}];
});
dispatch_group_enter(group);
dispatch_group_async(group, serialQueue, ^{
// 网络请求三
[WebClick getDataSuccess:^{
dispatch_group_leave(group);
} failure:^(NSString *errorString) {
dispatch_group_leave(group);
}];
});
// 所有网络请求结束后会来到这个方法
dispatch_group_notify(group, serialQueue, ^{
dispatch_async(dispatch_get_global_queue(0, 0), ^{
dispatch_async(dispatch_get_main_queue(), ^{
// 刷新UI
});
});
});
66、解决openUrl延时问题
// 方法一
dispatch_async(dispatch_get_main_queue(), ^{
UIApplication *application = [UIApplication sharedApplication];
if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) {
[application openURL:URL options:@{}
completionHandler:nil];
} else {
[application openURL:URL];
}
});
// 方法二
[self performSelector:@selector(redirectToURL:) withObject:url afterDelay:0.1];
- (void) redirectToURL
{
UIApplication *application = [UIApplication sharedApplication];
if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) {
[application openURL:URL options:@{}
completionHandler:nil];
} else {
[application openURL:URL];
}
}
67、页面跳转实现翻转动画
// modal方式
TestViewController *vc = [[TestViewController alloc] init];
vc.view.backgroundColor = [UIColor redColor];
vc.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self presentViewController:vc animated:YES completion:nil];
// push方式
TestViewController *vc = [[TestViewController alloc] init];
vc.view.backgroundColor = [UIColor redColor];
[UIView beginAnimations:@"View Flip" context:nil];
[UIView setAnimationDuration:0.80];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:self.navigationController.view cache:NO];
[self.navigationController pushViewController:vc animated:YES];
[UIView commitAnimations];
68、tableView实现无限滚动
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGFloat actualPosition = scrollView.contentOffset.y;
CGFloat contentHeight = scrollView.contentSize.height - scrollView.frame.size.height;
if (actualPosition >= contentHeight) {
[self.dataArr addObjectsFromArray:self.dataArr];
[self.tableView reloadData];
}
}
69、代码方式调整屏幕亮度
// brightness属性值在0-1之间,0代表最小亮度,1代表最大亮度
[[UIScreen mainScreen] setBrightness:0.5];
70、获取当前应用CUP用量
float cpu_usage()
{
kern_return_t kr;
task_info_data_t tinfo;
mach_msg_type_number_t task_info_count;
task_info_count = TASK_INFO_MAX;
kr = task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)tinfo, &task_info_count);
if (kr != KERN_SUCCESS) {
return -1;
}
task_basic_info_t basic_info;
thread_array_t thread_list;
mach_msg_type_number_t thread_count;
thread_info_data_t thinfo;
mach_msg_type_number_t thread_info_count;
thread_basic_info_t basic_info_th;
uint32_t stat_thread = 0; // Mach threads
basic_info = (task_basic_info_t)tinfo;
// get threads in the task
kr = task_threads(mach_task_self(), &thread_list, &thread_count);
if (kr != KERN_SUCCESS) {
return -1;
}
if (thread_count > 0)
stat_thread += thread_count;
long tot_sec = 0;
long tot_usec = 0;
float tot_cpu = 0;
int j;
for (j = 0; j < (int)thread_count; j++)
{
thread_info_count = THREAD_INFO_MAX;
kr = thread_info(thread_list[j], THREAD_BASIC_INFO,
(thread_info_t)thinfo, &thread_info_count);
if (kr != KERN_SUCCESS) {
return -1;
}
basic_info_th = (thread_basic_info_t)thinfo;
if (!(basic_info_th->flags & TH_FLAGS_IDLE)) {
tot_sec = tot_sec + basic_info_th->user_time.seconds + basic_info_th->system_time.seconds;
tot_usec = tot_usec + basic_info_th->user_time.microseconds + basic_info_th->system_time.microseconds;
tot_cpu = tot_cpu + basic_info_th->cpu_usage / (float)TH_USAGE_SCALE * 100.0;
}
} // for each thread
kr = vm_deallocate(mach_task_self(), (vm_offset_t)thread_list, thread_count * sizeof(thread_t));
assert(kr == KERN_SUCCESS);
return tot_cpu;
}
71、float数据取整四舍五入
CGFloat f = 4.65;
NSLog(@"%d", (int)f); // 打印结果4
CGFloat f = 4.65;
NSLog(@"%d", (int)round(f)); // 打印结果5
72、删除UISearchBar系统默认边框
// 方法一
searchBar.searchBarStyle = UISearchBarStyleMinimal;
// 方法二
[searchBar setBackgroundImage:[[UIImage alloc]init]];
// 方法三
searchBar.barTintColor = [UIColor whiteColor];
73、为UICollectionViewCell设置圆角和阴影
cell.contentView.layer.cornerRadius = 2.0f;
cell.contentView.layer.borderWidth = 1.0f;
cell.contentView.layer.borderColor = [UIColor clearColor].CGColor;
cell.contentView.layer.masksToBounds = YES;
cell.layer.shadowColor = [UIColor lightGrayColor].CGColor;
cell.layer.shadowOffset = CGSizeMake(0, 2.0f);
cell.layer.shadowRadius = 2.0f;
cell.layer.shadowOpacity = 1.0f;
cell.layer.masksToBounds = NO;
cell.layer.shadowPath = [UIBezierPath bezierPathWithRoundedRect:cell.bounds cornerRadius:cell.contentView.layer.cornerRadius].CGPath;
74、让正在滑动的scrollView停止滚动(不是禁止,而是暂时停止滚动)
[scrollView setContentOffset:scrollView.contentOffset animated:NO];
75、使用xib设置UIView的边框、圆角
圆角和边框看下图即可设置
![](http://upload-images.jianshu.io/upload_images/1432270-92361b4d420ac296.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
但是增加layer.borderColor的keyPath设置边框颜色并不能起作用,后来查了资料,这里应该用layer.borderUIColor,但是这里设置的颜色不起作用,无论设置什么颜色显示出来的都是黑色的。后来又去查了下,有种解决方案是给CALayer添加一个分类,提供一个
- (void)setBorderUIColor:(UIColor *)color;
方法就可以解决了,实现如下:
![](http://upload-images.jianshu.io/upload_images/1432270-1fc7e7ca02eca962.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
#import "CALayer+BorderColor.h"
@implementation CALayer (BorderColor)
- (void)setBorderUIColor:(UIColor *)color
{
self.borderColor = color.CGColor;
}
76、根据经纬度获取城市等信息
// 创建经纬度
CLLocation *location = [[CLLocation alloc] initWithLatitude:latitude longitude:longitude];
//创建一个译码器
CLGeocoder *cLGeocoder = [[CLGeocoder alloc] init];
[cLGeocoder reverseGeocodeLocation:userLocation completionHandler:^(NSArray *placemarks, NSError *error) {
CLPlacemark *place = [placemarks objectAtIndex:0];
// 位置名
NSLog(@"name,%@",place.name);
// 街道
NSLog(@"thoroughfare,%@",place.thoroughfare);
// 子街道
NSLog(@"subThoroughfare,%@",place.subThoroughfare);
// 市
NSLog(@"locality,%@",place.locality);
// 区
NSLog(@"subLocality,%@",place.subLocality);
// 国家
NSLog(@"country,%@",place.country);
}
}];
/* CLPlacemark中属性含义
name 地名
thoroughfare 街道
subThoroughfare 街道相关信息,例如门牌等
locality 城市
subLocality 城市相关信息,例如标志性建筑
administrativeArea 直辖市
subAdministrativeArea 其他行政区域信息(自治区等)
postalCode 邮编
ISOcountryCode 国家编码
country 国家
inlandWater 水源,湖泊
ocean 海洋
areasOfInterest 关联的或利益相关的地标
*/
77、如何防止添加多个NSNotification观察者?
// 解决方案就是添加观察者之前先移除下这个观察者
[[NSNotificationCenter defaultCenter] removeObserver:observer name:name object:object];
[[NSNotificationCenter defaultCenter] addObserver:observer selector:selector name:name object:object];
78、将一个xib添加到另外一个xib上
// 假设你的自定义view名字为CustomView,你需要在CustomView.m中重写 `- (instancetype)initWithCoder:(NSCoder *)aDecoder` 方法,代码如下:
- (instancetype)initWithCoder:(NSCoder *)aDecoder {
if ((self = [super initWithCoder:aDecoder])) {
[self addSubview:[[[NSBundle mainBundle] loadNibNamed:@"CustomView" owner:self options:nil] objectAtIndex:0]];
}
return self;
}
![](http://upload-images.jianshu.io/upload_images/1432270-1baa2a4dd2e2d08f.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
79、处理字符串,使其首字母大写
NSString *str = @"abcdefghijklmn";
NSString *resultStr;
if (str && str.length > 0) {
resultStr = [str stringByReplacingCharactersInRange:NSMakeRange(0,1) withString:[[str substringToIndex:1] capitalizedString]];
}
NSLog(@"%@", resultStr);
80、判断一个UIAlertView/UIAlertController是否显示
// UIAlertView自带属性
if (alert.visible)
{
NSLog(@"显示了");
} else {
NSLog(@"未显示");
}
// UIAlertController没有visible属性,需要自己判断,添加一个全局变量 BOOL visible
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"message" preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *alertAction = [UIAlertAction actionWithTitle:@"ActionTitle" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
self.visible = NO;
}];
UIAlertAction *calcelAction = [UIAlertAction actionWithTitle:@"calcelTitle" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
self.visible = NO;
}];
[alertController addAction:alertAction];
[alertController addAction:calcelAction];
[self presentViewController:alertController animated:YES completion:^{
self.visible = YES;
}];
81、获取字符串中的数字
- (NSString *)getNumberFromStr:(NSString *)str
{
NSCharacterSet *nonDigitCharacterSet = [[NSCharacterSet decimalDigitCharacterSet] invertedSet];
return [[str componentsSeparatedByCharactersInSet:nonDigitCharacterSet] componentsJoinedByString:@""];
}
NSLog(@"%@", [self getNumberFromStr:@"a0b0c1d2e3f4fda8fa8fad9fsad23"]); // 00123488923
82、为UIView的某个方向添加边框
// 添加UIView分类
// UIView+WZB.h
#import <UIKit/UIKit.h>
/**
边框方向
- WZBBorderDirectionTop: 顶部
- WZBBorderDirectionLeft: 左边
- WZBBorderDirectionBottom: 底部
- WZBBorderDirectionRight: 右边
*/
typedef NS_ENUM(NSInteger, WZBBorderDirectionType) {
WZBBorderDirectionTop = 0,
WZBBorderDirectionLeft,
WZBBorderDirectionBottom,
WZBBorderDirectionRight
};
@interface UIView (WZB)
/**
为UIView的某个方向添加边框
@param direction 边框方向
@param color 边框颜色
@param width 边框宽度
*/
- (void)wzb_addBorder:(WZBBorderDirectionType)direction color:(UIColor *)color width:(CGFloat)width;
@end
// UIView+WZB.m
#import "UIView+WZB.h"
@implementation UIView (WZB)
- (void)wzb_addBorder:(WZBBorderDirectionType)direction color:(UIColor *)color width:(CGFloat)width
{
CALayer *border = [CALayer layer];
border.backgroundColor = color.CGColor;
switch (direction) {
case WZBBorderDirectionTop:
{
border.frame = CGRectMake(0.0f, 0.0f, self.bounds.size.width, width);
}
break;
case WZBBorderDirectionLeft:
{
border.frame = CGRectMake(0.0f, 0.0f, width, self.bounds.size.height);
}
break;
case WZBBorderDirectionBottom:
{
border.frame = CGRectMake(0.0f, self.bounds.size.height - width, self.bounds.size.width, width);
}
break;
case WZBBorderDirectionRight:
{
border.frame = CGRectMake(self.bounds.size.width - width, 0, width, self.bounds.size.height);
}
break;
default:
break;
}
[self.layer addSublayer:border];
}
83、通过属性设置UISwitch、UIProgressView等控件的宽高
mySwitch.transform = CGAffineTransformMakeScale(5.0f, 5.0f);
progressView.transform = CGAffineTransformMakeScale(5.0f, 5.0f);
84、自动搜索功能,用户连续输入的时候不搜索,用户停止输入的时候自动搜索(我这里设置的是0.5s,可根据需求更改)
// 输入框文字改变的时候调用
-(void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText{
// 先取消调用搜索方法
[NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(searchNewResult) object:nil];
// 0.5秒后调用搜索方法
[self performSelector:@selector(searchNewResult) withObject:nil afterDelay:0.5];
}
85、修改UISearchBar的占位文字颜色
// 方法一(推荐使用)
UITextField *searchField = [searchBar valueForKey:@"_searchField"];
[searchField setValue:[UIColor blueColor] forKeyPath:@"_placeholderLabel.textColor"];
// 方法二(已过期)
[[UILabel appearanceWhenContainedIn:[UISearchBar class], nil] setTextColor:[UIColor redColor]];
// 方法三(已过期)
NSDictionary *placeholderAttributes = @{NSForegroundColorAttributeName : [UIColor redColor], NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue" size:15],};
NSAttributedString *attributedPlaceholder = [[NSAttributedString alloc] initWithString:searchBar.placeholder attributes:placeholderAttributes];
[[UITextField appearanceWhenContainedIn:[UISearchBar class], nil] setAttributedPlaceholder:attributedPlaceholder];
86、某个界面多个事件同时响应引起的问题(比如,两个button同时按push到新界面,两个都会响应,可能导致push重叠)
// UIView有个属性叫做exclusiveTouch,设置为YES后,其响应事件会和其他view互斥(有其他view事件响应的时候点击它不起作用)
view.exclusiveTouch = YES;
// 一个一个设置太麻烦了,可以全局设置
[[UIView appearance] setExclusiveTouch:YES];
// 或者只设置button
[[UIButton appearance] setExclusiveTouch:YES];
87、修改tabBar的frame
// 子类化UITabBarViewController,我这里以修改tabBar高度为例,重写viewWillLayoutSubviews方法
#import "WZBTabBarViewController.h"
@interface WZBTabBarViewController ()
@end
@implementation WZBTabBarViewController
- (void)viewWillLayoutSubviews {
CGRect tabFrame = self.tabBar.frame;
tabFrame.size.height = 100;
tabFrame.origin.y = self.view.frame.size.height - 100;
self.tabBar.frame = tabFrame;
}
@end
88、修改键盘背景颜色
// 设置某个键盘颜色
textField.keyboardAppearance = UIKeyboardAppearanceAlert;
// 设置工程中所有键盘颜色
[[UITextField appearance] setKeyboardAppearance:UIKeyboardAppearanceAlert];
89、修改image颜色
UIImage *image = [UIImage imageNamed:@"test"];
imageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
CGRect rect = CGRectMake(0, 0, image.size.width, image.size.height);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextClipToMask(context, rect, image.CGImage);
CGContextSetFillColorWithColor(context, [[UIColor redColor] CGColor]);
CGContextFillRect(context, rect);
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImage *flippedImage = [UIImage imageWithCGImage:img.CGImage scale:1.0 orientation: UIImageOrientationDownMirrored];
imageView.image = flippedImage;
90、动画执行removeFromSuperview
[UIView animateWithDuration:0.2
animations:^{
view.alpha = 0.0f;
} completion:^(BOOL finished){
[view removeFromSuperview];
}];
91、启动页显示延时
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
// 延时10s
sleep(10);
return YES;
}
92、设置UIButton高亮时的背景颜色
// 方法一、子类化UIButton,重写setHighlighted:方法,代码如下
#import "WZBButton.h"
@implementation WZBButton
- (void)setHighlighted:(BOOL)highlighted {
[super setHighlighted:highlighted];
UIColor *normalColor = [UIColor greenColor];
UIColor *highlightedColor = [UIColor redColor];
self.backgroundColor = highlighted ? highlightedColor : normalColor;
}
// 方法二、利用setBackgroundImage:forState:方法
[button setBackgroundImage:[self imageWithColor:[UIColor blueColor]] forState:UIControlStateHighlighted];
- (UIImage *)imageWithColor:(UIColor *)color {
CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [color CGColor]);
CGContextFillRect(context, rect);
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
93、关于图片拉伸
推荐看这个博客,讲的很详细http://blog.csdn.net/q199109106q/article/details/8615661
94、利用runtime获取一个类所有属性
- (NSArray *)allPropertyNames:(Class)aClass
{
unsigned count;
objc_property_t *properties = class_copyPropertyList(aClass, &count);
NSMutableArray *rv = [NSMutableArray array];
unsigned i;
for (i = 0; i < count; i++)
{
objc_property_t property = properties[i];
NSString *name = [NSString stringWithUTF8String:property_getName(property)];
[rv addObject:name];
}
free(properties);
return rv;
}
95、设置textView的某段文字变成其他颜色
- (void)setupTextView:(UITextView *)textView text:(NSString *)text color:(UIColor *)color {
NSMutableAttributedString *string = [[NSMutableAttributedString alloc]initWithString:textView.text];
[string addAttribute:NSForegroundColorAttributeName value:color range:[textView.text rangeOfString:text]];
[textView setAttributedText:string];
}
96、让push跳转动画像modal跳转动画那样效果(从下往上推上来)
- (void)push
{
TestViewController *vc = [[TestViewController alloc] init];
vc.view.backgroundColor = [UIColor redColor];
CATransition* transition = [CATransition animation];
transition.duration = 0.4f;
transition.type = kCATransitionMoveIn;
transition.subtype = kCATransitionFromTop;
[self.navigationController.view.layer addAnimation:transition forKey:kCATransition];
[self.navigationController pushViewController:vc animated:NO];
}
- (void)pop
{
CATransition* transition = [CATransition animation];
transition.duration = 0.4f;
transition.type = kCATransitionReveal;
transition.subtype = kCATransitionFromBottom;
[self.navigationController.view.layer addAnimation:transition forKey:kCATransition];
[self.navigationController popViewControllerAnimated:NO];
}
97、上传图片太大,压缩图片
-(UIImage *)resizeImage:(UIImage *)image
{
float actualHeight = image.size.height;
float actualWidth = image.size.width;
float maxHeight = 300.0;
float maxWidth = 400.0;
float imgRatio = actualWidth/actualHeight;
float maxRatio = maxWidth/maxHeight;
float compressionQuality = 0.5;//50 percent compression
if (actualHeight > maxHeight || actualWidth > maxWidth)
{
if(imgRatio < maxRatio)
{
//adjust width according to maxHeight
imgRatio = maxHeight / actualHeight;
actualWidth = imgRatio * actualWidth;
actualHeight = maxHeight;
}
else if(imgRatio > maxRatio)
{
//adjust height according to maxWidth
imgRatio = maxWidth / actualWidth;
actualHeight = imgRatio * actualHeight;
actualWidth = maxWidth;
}
else
{
actualHeight = maxHeight;
actualWidth = maxWidth;
}
}
CGRect rect = CGRectMake(0.0, 0.0, actualWidth, actualHeight);
UIGraphicsBeginImageContext(rect.size);
[image drawInRect:rect];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
NSData *imageData = UIImageJPEGRepresentation(img, compressionQuality);
UIGraphicsEndImageContext();
return [UIImage imageWithData:imageData];
}
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作者:杂雾无尘
链接:http://www.jianshu.com/p/9fcd37c0ea05
來源:简书
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