iOS - Tips

自定义cell选中背景色

UIView *bgColorView = [[UIView alloc] init];
bgColorView.backgroundColor = [UIColor redColor];
[cell setSelectedBackgroundView:bgColorView];

NSURL获取字符串

NSString *urlString = myURL.absoluteString;

获取手机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);

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];
}

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;
}

屏幕翻转相关

/** 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;
}

收起键盘--方便

[[[UIApplication sharedApplication] keyWindow] endEditing:YES];

修改UITextField的placeholder字体颜色大小

[textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];
[textField setValue:[UIFont boldSystemFontOfSize:16] forKeyPath:@"_placeholderLabel.font"];

获取UIWindow

• 当年直接用这个获取[UIApplication sharedApplication].keyWindow有时候获取到的是一个nil

+(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;
}

去除数组中重复的对象.

    NSArray * arr = @[@"1",@"2",@"2",@"3",];
    NSArray *newArr = [arr valueForKeyPath:@"@distinctUnionOfObjects.self"];
    NSLog(@"newArr = %@",newArr);

• 打印结果
  

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;
}

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;
}

转自: http://www.jianshu.com/p/1ff9e44ccc78 感谢作者