ios touch 从一个按钮移动到另一个按钮

Question

我有两个自定义 uibutton。

@interface myButton : UIButton

我覆盖了几个方法，比如

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
  // do something
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    [super touchesMoved:touches withEvent:event];
    [self.nextResponder touchesMoved:touches withEvent:event];
    UITouch *touch = [touches anyObject];
    CGPoint touchPoint = [touch locationInView:self];

    if (!CGRectContainsPoint(self.bounds, touchPoint)) {
        [self touchesCancelled:touches withEvent:event];
    }
    return;
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
   // do something
}

-(void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
    [super touchesCancelled:touches withEvent:event];
    return;
}

我想要的是，当我触摸一个按钮时，我可以继续将我的触摸移动到另一个按钮。当触摸超出我触摸的第一个按钮的范围时，我厌倦了调用 touchesCancelled。所以我“认为”然后我移动到另一个按钮，这将是一个新的触摸事件。但它不是这样工作的。

我做错了什么吗？或者 touchesCancelled 方法不用于此目的？提前致谢!

Answer 1

您的怀疑是正确的，这不是 touchesCancelled:withEvent: 的用途。来自文档:

This method is invoked when the Cocoa Touch framework receives a system interruption requiring cancellation of the touch event; for this, it generates a UITouch object with a phase of UITouchPhaseCancel. The interruption is something that might cause the application to be no longer active or the view to be removed from the window.

如果您的用户收到来电、短信或他们的闹钟响起等，您的响应者将收到触摸取消事件。它应该用于清除在其他触摸事件中建立的任何状态信息。

似乎您想在触摸中更改与触摸事件关联的响应者，即当您从第一个按钮的边界拖动触摸并输入第二个按钮的触摸时，它应该成为接收触摸事件的响应者.不幸的是，这不是响应者设计的工作方式。一旦 UIView 被识别为响应者，如 hitTest:withEvent: 中返回的那样，这将是接收触摸事件的 UIView。

实现你想要的可能的锻炼是在包含你的两个按钮。然后你的 super View 将收到触摸事件，你可以根据你在哪个按钮的框架内采取行动:

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    for (UITouch *touch in touches)
    {
        CGPoint touchLocation = [touch locationInView:self.view];

        UIButton *button;
        if (CGRectContainsPoint(self.button1.frame, touchLocation))
        {
            button = self.button1;
            NSLog(@"touchesMoved: First Button");
        }
        else if (CGRectContainsPoint(self.button2.frame, touchLocation))
        {
            button = self.button2;
            NSLog(@"touchesMoved: Second Button");
        }

        // Do something with button...
    }
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    for (UITouch *touch in touches)
    {
        CGPoint touchLocation = [touch locationInView:self.view];

        UIButton *button;
        if (CGRectContainsPoint(self.button1.frame, touchLocation))
        {
            button = self.button1;
            NSLog(@"touchesMoved: First Button");
        }
        else if (CGRectContainsPoint(self.button2.frame, touchLocation))
        {
            button = self.button2;
            NSLog(@"touchesMoved: Second Button");
        }

        // Do something with button...
    }
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
    for (UITouch *touch in touches)
    {
        CGPoint touchLocation = [touch locationInView:self.view];

        UIButton *button;
        if (CGRectContainsPoint(self.button1.frame, touchLocation))
        {
            button = self.button1;
            NSLog(@"touchesEnded: First Button");
        }
        else if (CGRectContainsPoint(self.button2.frame, touchLocation))
        {
            button = self.button2;
            NSLog(@"touchesEnded: Second Button");
        }

        // Do something with button...
    }
}