UIapplictaion 的工作流程&windows
#import "MXAppDelegate.h"
@implementation MXAppDelegate
/**
* app启动完毕后就会调用
*/
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
NSLog(@"%@", self.window);
NSLog(@"didFinishLaunchingWithOptions");
// Override point for customization after application launch.
return YES;
}
- (void)applicationWillResignActive:(UIApplication *)application
{
// Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
// Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
}
/**
* app进入后台的时候调用
*
* 一般在这里保存应用的数据(游戏数据,比如暂停游戏)
*/
- (void)applicationDidEnterBackground:(UIApplication *)application
{
NSLog(@"applicationDidEnterBackground");
// Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
// If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
}
- (void)applicationWillEnterForeground:(UIApplication *)application
{
NSLog(@"applicationWillEnterForeground");
// Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
}
- (void)applicationDidBecomeActive:(UIApplication *)application
{
// Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
}
/**
* 清除不需要再使用的内存
*/
- (void)applicationDidReceiveMemoryWarning:(UIApplication *)application
{
NSLog(@"applicationDidReceiveMemoryWarning");
}
- (void)applicationWillTerminate:(UIApplication *)application
{
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
}
／／UIWindow
// 旋转事件 --> UIApplication --> UIWindow
/**
* 程序启动完毕就会调用一次
*/
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
// 1.创建window
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// 2.设置window的背景色
self.window.backgroundColor = [UIColor whiteColor];
MjOneViewController *one = [[MjOneViewController alloc] init];
// [self.window addSubview:one.view];
self.window.rootViewController = one;
// 3.显示window
[self.window makeKeyAndVisible];
return YES;
}
一.UIPickerView
1.UIPickerView的常见属性
// 数据源(用来告诉UIPickerView有多少列多少行)
@property(nonatomic,assign) id<UIPickerViewDataSource> dataSource;
// 代理(用来告诉UIPickerView每1列的每1行显示什么内容,监听UIPickerView的选择)
@property(nonatomic,assign) id<UIPickerViewDelegate> delegate;
// 是否要显示选中的指示器
@property(nonatomic) BOOL showsSelectionIndicator;
// 一共有多少列
@property(nonatomic,readonly) NSInteger numberOfComponents;
2.UIPickerView的常见方法
// 重新刷新所有列
- (void)reloadAllComponents;
// 重新刷新第component列
- (void)reloadComponent:(NSInteger)component;
// 主动选中第component列的第row行
- (void)selectRow:(NSInteger)row inComponent:(NSInteger)component animated:(BOOL)animated;
// 获得第component列的当前选中的行号
- (NSInteger)selectedRowInComponent:(NSInteger)component;
3.数据源方法(UIPickerViewDataSource)
// 一共有多少列
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView;
// 第component列一共有多少行
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component;
4.代理方法(UIPickerViewDelegate)
// 第component列的宽度是多少
- (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component;
// 第component列的行高是多少
- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component;
// 第component列第row行显示什么文字
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component;
// 第component列第row行显示怎样的view(内容)
- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view;
// 选中了pickerView的第component列第row行
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component;
二.UIDatePicker
1.常见属性
// datePicker的显示模式
@property (nonatomic) UIDatePickerMode datePickerMode;
// 显示的区域语言
@property (nonatomic, retain) NSLocale *locale;
2.监听UIDatePicker的选择
* 因为UIDatePicker继承自UIControl,所以通过addTarget:...监听
// UIApplication 启动原理
三.程序启动的完整过程
1.main函数
2.UIApplicationMain
* 创建UIApplication对象
* 创建UIApplication的delegate对象
3.delegate对象开始处理(监听)系统事件(没有storyboard)
* 程序启动完毕的时候, 就会调用代理的application:didFinishLaunchingWithOptions:方法
* 在application:didFinishLaunchingWithOptions:中创建UIWindow
* 创建和设置UIWindow的rootViewController
* 显示窗口
3.根据Info.plist获得最主要storyboard的文件名,加载最主要的storyboard(有storyboard)
* 创建UIWindow
* 创建和设置UIWindow的rootViewController
* 显示窗口
