Ios iPad UI键盘隐藏/退出/取消按钮事件处理程序？

你能看到iPad键盘右下角的按钮吗

我想要访问该按钮的事件处理程序，因为，当按下该按钮时，我需要管理一些逻辑

我尝试的解决方案包括使用UIKeyboardWillHideNotification通知，如下所示：

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(hideKeyboardTapped:)
                                             name:UIKeyboardWillHideNotification
                                           object:nil];

然而，每次键盘被关闭时，包括按下搜索取消按钮、在背景上进行手势点击等，都会调用此功能；所有这些都有稍微不同的逻辑

所以我只需要有一套逻辑，当特定的“隐藏键盘”按钮被按下时

ui键盘由

ui搜索栏激活（适用于需要额外信息的用户）

任何帮助都将不胜感激；我会回答你可能有的任何问题。
没有一个官方的、苹果认可的方法来做到这一点

如果你不介意随意使用私有类，可能会让你被应用商店拒绝，那么有一种不受支持的方法。基本上，您可以监听键盘的
activeKey
属性的更改，如果新的活动键的名称为
“dismise key”
，则按下dismise键：

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self)
    {
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidShow:) name:UIKeyboardDidShowNotification object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
    }
    return self;
}

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{
    if ([keyPath isEqualToString:@"activeKey"])
    {
        id activeKey = [object valueForKey:keyPath];
        NSString *keyName = [activeKey valueForKey:@"name"];
        if ([keyName isEqualToString:@"Dismiss-Key"])
        {
            [self didTapDismissKey];
        }
    }
    else
    {
        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
    }
}

- (void)dealloc
{
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

- (void)keyboardDidShow:(NSNotification *)notification
{
    // Search for the UIKeyboardLayoutStar class, which seems to manage layout for the keyboard, and observe its activeKey property
    UIWindow *topWindow = [UIApplication sharedApplication].windows.lastObject;
    [self traverseViewHierarchyWithView:topWindow block:^(UIView *view, BOOL *stop) {

        if ([view isKindOfClass:NSClassFromString(@"UIKeyboardLayoutStar")])
        {
            [view addObserver:self forKeyPath:@"activeKey" options:0 context:NULL];
        }
    }];
}

- (void)keyboardWillHide:(NSNotification *)notification
{
    // Don't forget to remove the controller as an observer!
    UIWindow *topWindow = [UIApplication sharedApplication].windows.lastObject;
    [self traverseViewHierarchyWithView:topWindow block:^(UIView *view, BOOL *stop) {

        if ([view isKindOfClass:NSClassFromString(@"UIKeyboardLayoutStar")])
        {
            [view removeObserver:self forKeyPath:@"activeKey"];
        }
    }];
}

- (BOOL)traverseViewHierarchyWithView:(UIView *)view block:(void (^)(UIView *, BOOL *))block
{
    BOOL stop = NO;
    block(view, &stop);

    if (stop)
    {
        return YES;
    }

    for (UIView *subview in view.subviews)
    {
        if ([self traverseViewHierarchyWithView:subview block:block])
        {
            return YES;
        }
    }

    return NO;
}

- (void)didTapDismissKey
{
    NSLog(@"Dismiss key tapped");
}

在iOS 7 iPad模拟器上测试，可以正常工作。
我不知道你是否可以将监听器放在键盘的一个按钮上，但你可以尝试在视图上设置一些布尔值，可以打开/关闭你想要或不想要处理的事件（我会这样处理），例如：

在您创建的类中添加自定义通知观察者/侦听器
要执行事件的方法

在将触发通知的控制器上添加Apple默认键盘隐藏侦听器

然后，在可以触发事件的视图上。。。设置布尔值以激活/停用事件操作

@另一类

-（无效）视图将显示：（BOOL）动画{

}

-（无效）视图将消失：（BOOL）已设置动画{

}

@触发类

-(void)viewWillAppear:(BOOL)animated{

        self.isNotificationNeeded = NO;
        [[NSNotificationCenter defaultCenter]addObserver:self
                                                selector:@selector(onKeyboardHide:)
                                                    name:UIKeyboardWillHideNotification
                                                  object:nil];
    }

    -(void)viewWillDisappear:(BOOL)animated{

        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];

    }

    -(void)onKeyboardHide:(id)sender{

        //When your event is Happening
        if (self.isNotificationNeeded == YES) {

            NSNotification *n = [NSNotification notificationWithName:@"doSomethingNotification" object:nil];
            [[NSNotificationCenter defaultCenter] postNotification:n];


            self.isNotificationNeeded = NO;
        }


    }

    -(void)userClickedCancelButton{

        //If this is a keyboard hide event that you don't want to trigger
        self.isNotificationNeeded = NO; 

    }

    //SearchBarDelegate
    -(BOOL)searchBarShouldBeginEditing:(UISearchBar *)searchBar{

        self.isNotificationNeeded = YES; //If your event can happen from here

        return YES;


    }

我不知道这是可能的。
[[NSNotificationCenter defaultCenter] removeObserver:self name:@"doSomethingNotification" object:nil];

-(void)viewWillAppear:(BOOL)animated{

        self.isNotificationNeeded = NO;
        [[NSNotificationCenter defaultCenter]addObserver:self
                                                selector:@selector(onKeyboardHide:)
                                                    name:UIKeyboardWillHideNotification
                                                  object:nil];
    }

    -(void)viewWillDisappear:(BOOL)animated{

        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];

    }

    -(void)onKeyboardHide:(id)sender{

        //When your event is Happening
        if (self.isNotificationNeeded == YES) {

            NSNotification *n = [NSNotification notificationWithName:@"doSomethingNotification" object:nil];
            [[NSNotificationCenter defaultCenter] postNotification:n];


            self.isNotificationNeeded = NO;
        }


    }

    -(void)userClickedCancelButton{

        //If this is a keyboard hide event that you don't want to trigger
        self.isNotificationNeeded = NO; 

    }

    //SearchBarDelegate
    -(BOOL)searchBarShouldBeginEditing:(UISearchBar *)searchBar{

        self.isNotificationNeeded = YES; //If your event can happen from here

        return YES;


    }