无法将手势识别器应用于导航栏 [英] Trouble applying gesture recognizer to navigationbar

问题描述

在我的iPad应用程序中，我在屏幕上有多个视图.

In my iPad Application I have multiple views on a screen.

我想做的是在导航栏上双击手势识别器.但是我没有成功，但是当将相同的手势识别器应用于该视图时，它就可以工作.

What I want to do is apply a double tap Gesture Recognizer to the Navigation Bar. But I had no success, however when the same gesture recognizer applied to that view it works.

这是我正在使用的代码:

Here is the code I am using:

// Create gesture recognizer, notice the selector method
UITapGestureRecognizer *oneFingerTwoTaps = 
[[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerTwoTaps)] autorelease];

// Set required taps and number of touches
[oneFingerTwoTaps setNumberOfTapsRequired:2];
[oneFingerTwoTaps setNumberOfTouchesRequired:1];

[self.view addGestureRecognizer:oneFingerTwoTaps];

这可以在视图上使用，但是完成后:

This works on view, but when this is done:

[self.navigationController.navigationBar addGestureRecognizer:oneFingerTwoTaps]

不起作用.

推荐答案

为此，您需要继承UINavigationBar的子类，重写其中的init按钮，然后在其中添加手势识别器.

For this you need to subclass UINavigationBar, override the init button in it and add your gesture recognizer there.

因此，假设您创建了一个名为'CustomNavigationBar'的子类-在您的m文件中，您将具有如下所示的init方法:

So say you make a subclass called 'CustomNavigationBar' - in your m file you would have an init method like this:

- (id)initWithCoder:(NSCoder *)aDecoder
{
    if ((self = [super initWithCoder:aDecoder])) 
    {
        UISwipeGestureRecognizer *swipeRight;
        swipeRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(didSwipeRight:)];
        [swipeRight setDirection:UISwipeGestureRecognizerDirectionRight];
        [swipeRight setNumberOfTouchesRequired:1];
        [swipeRight setEnabled:YES];
        [self addGestureRecognizer:swipeRight];
    }
    return self;
}

然后，您需要在界面构建器中将导航栏的类名称设置为子类的名称.

Then you need to set the class name of your navigation bar in interface builder to the name of your subclass.

将代理协议添加到导航栏也很方便，以侦听手势结尾处发送的方法.例如-在上述向右滑动的情况下:

Also it's handy to add a delegate protocol to your navigation bar to listen for methods sent at the end of your gestures. For example - in the case of the above swipe right:

@protocol CustomNavigationbarDelegate <NSObject>
    - (void)customNavBarDidFinishSwipeRight;
@end

然后在m文件中-在手势识别方法(无论您采用哪种方法)上，您都可以触发此委托方法.

then in the m file - on the gesture recognised method (whatever you make it) you can trigger this delegate method.

希望这会有所帮助

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