iOS：提示框(警告框)控件UIActionSheet的详解

@property(nonatomic,assign) id<UIActionSheetDelegate> delegate;    // 代理

@property(nonatomic,copy) NSString *title;  //标题

@property(nonatomic) UIActionSheetStyle actionSheetStyle; //风格类型

@property(nonatomic,readonly) NSInteger numberOfButtons; //按钮数量

@property(nonatomic) NSInteger cancelButtonIndex;    //取消按钮的索引

@property(nonatomic) NSInteger destructiveButtonIndex;  //红色按钮索引

@property(nonatomic,readonly) NSInteger firstOtherButtonIndex; //其他第一个按钮索引

@property(nonatomic,readonly,getter=isVisible) BOOL visible; //是否可见

方法：

※创建实例的初始化方法

- (instancetype)initWithTitle:(NSString *)title delegate:(id<UIActionSheetDelegate>)delegate cancelButtonTitle:(NSString *)cancelButtonTitle destructiveButtonTitle:(NSString *)destructiveButtonTitle otherButtonTitles:(NSString *)otherButtonTitles, ...("Use UIAlertController instead.”);

※添加按钮,返回它的索引

- (NSInteger)addButtonWithTitle:(NSString *)title;    

※返回指定索引的按钮文字

- (NSString *)buttonTitleAtIndex:(NSInteger)buttonIndex;

※显示在工具栏

- (void)showFromToolbar:(UIToolbar *)view;

※显示在导航栏

- (void)showFromTabBar:(UITabBar *)view;

※显示在工具栏按钮上

- (void)showFromBarButtonItem:(UIBarButtonItem *)item animated:(BOOL)animated ;

※在指定区域和视图上显示

- (void)showFromRect:(CGRect)rect inView:(UIView *)view animated:(BOOL)animated;

※在视图上显示

- (void)showInView:(UIView *)view;

※按钮消失

- (void)dismissWithClickedButtonIndex:(NSInteger)buttonIndex animated:(BOOL)animated;

代理方法：

@protocol UIActionSheetDelegate <NSObject>

@optional

//点击一个按钮时触发的方法

- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex;

// 如果没有定义的委托,我们模拟一个点击取消按钮

- (void)actionSheetCancel:(UIActionSheet *)actionSheet;

 //将要显示警告框时触发的方

- (void)willPresentActionSheet:(UIActionSheet *)actionSheet; 

 //已经显示提示框时触发的方法

- (void)didPresentActionSheet:(UIActionSheet *)actionSheet; 

//提示框将要消失时触发的方法

- (void)actionSheet:(UIActionSheet *)actionSheet willDismissWithButtonIndex:(NSInteger)buttonIndex;

//提示框已经消失时触发的方法

- (void)actionSheet:(UIActionSheet *)actionSheet didDismissWithButtonIndex:(NSInteger)buttonIndex; 

@end

举例如下：类实现协议

@interface ViewController ()<UIActionSheetDelegate>

   1. //实例化

    //创建提示框实例
    UIActionSheet *actionSheet = [[UIActionSheet alloc]initWithTitle:@"title" delegate:self cancelButtonTitle:@"cance" destructiveButtonTitle:@"destructive" otherButtonTitles:@"button1", @"button2",nil];

  2. //设置风格

    //设置风格
    actionSheet.actionSheetStyle = UIActionSheetStyleBlackTranslucent;

 3. //设置代理

    //设置代理
    actionSheet.delegate = self;

  4. //在视图上显示

    //在视图上显示
    [actionSheet showInView:self.view];

实现代理方法：

#pragma mark-<UIActionSheetDelegate>

1.点击按钮时触发事件

//点击一个按钮时触发的方法
- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex
{
    NSLog(@"actionSheet: clickedButtonAtIndex:");
}

2.取消提示框时触发的事件

// 如果没有定义的委托,我们模拟一个点击取消按钮
- (void)actionSheetCancel:(UIActionSheet *)actionSheet
{
    NSLog(@"actionSheetCancel:");
}

3.提示框将要显示时触发的事件

//将要显示警告框时触发的方
- (void)willPresentActionSheet:(UIActionSheet *)actionSheet
{
    NSLog(@"willPresentActionSheet:");
}

4.显示提示框时触发的方法

//已经显示提示框时触发的方法
- (void)didPresentActionSheet:(UIActionSheet *)actionSheet
{
    NSLog(@"didPresentActionSheet:");
}

5.提示框将要消失时触发的方法

//提示框将要消失时触发的方法
- (void)actionSheet:(UIActionSheet *)actionSheet willDismissWithButtonIndex:(NSInteger)buttonIndex
{
    NSLog(@"actionSheet: willDismissWithButtonIndex:");
}

6.提示框消失时触发的方法

//提示框已经消失时触发的方法
- (void)actionSheet:(UIActionSheet *)actionSheet didDismissWithButtonIndex:(NSInteger)buttonIndex
{
    NSLog(@"actionSheet: didDismissWithButtonIndex:");
}

演示结果如下：

代理方法调用情况如下：

程序运行起来, 没有点击按钮时：

2015-09-30 19:34:29.647 提示框UIActionSheet[3866:212744] willPresentActionSheet:

点击任意按钮时：

2015-09-30 19:35:18.882 提示框UIActionSheet[3866:212744] actionSheet: clickedButtonAtIndex:
2015-09-30 19:35:18.883 提示框UIActionSheet[3866:212744] actionSheet: willDismissWithButtonIndex:
2015-09-30 19:35:19.297 提示框UIActionSheet[3866:212744] actionSheet: didDismissWithButtonIndex: