在UIButton上实现触摸取消

Question

我有一个子类UIButton，我把它做成了一个不规则的形状(平行四边形)，在那里我重写了触摸事件，所以它只接受形状内的触摸事件

我如何实现一个触摸事件像一个普通的UIButton，我可以取消触摸事件在点击和拖动手指在UIButton外面取消触摸。对于我现在的代码，如果我把手指拖到按钮里面，它会调用touchesCancelled事件。我使用TouchUpInside事件在UIButton中执行方法。下面是我的代码:

- (id)initWithFrame:(CGRect)frame withAngle:(AngleType)angle andColor:(UIColor *)color
{
    if ((self = [super initWithFrame:frame])){
        [self setImage:[Utils imageWithColor:color andSize:frame.size] forState:UIControlStateNormal];
        _path = [UIBezierPath new];
        self.angleType = angle;
        switch (angle) {
            case AngleLeft:
            {
                [_path moveToPoint:CGPointMake(0, elementHeight(self))];
                [_path addLineToPoint:CGPointMake(elementWidth(self), elementHeight(self))];
                [_path addLineToPoint:CGPointMake(elementWidth(self), 0)];
                [_path addLineToPoint:CGPointMake(15, 0)];
                [_path addLineToPoint:CGPointMake(0, elementHeight(self))];
            }
                break;
            case AngleRight:
            {
                [_path moveToPoint:CGPointMake(0, 0)];
                [_path addLineToPoint:CGPointMake(0, elementHeight(self))];
                [_path addLineToPoint:CGPointMake(elementWidth(self),elementHeight(self))];
                [_path addLineToPoint:CGPointMake(elementWidth(self) - 15, 0)];
                [_path addLineToPoint:CGPointMake(0, 0)];
            }
                break;
            case AngleBoth:
            {
                [_path moveToPoint:CGPointMake(15, 0)];
                [_path addLineToPoint:CGPointMake(0, elementHeight(self))];
                [_path addLineToPoint:CGPointMake(elementWidth(self) - 15, elementHeight(self))];
                [_path addLineToPoint:CGPointMake(elementWidth(self), 0)];
                [_path addLineToPoint:CGPointMake(15, 0)];
            }
                break;
            default:
                break;
        }
        CAShapeLayer *mask = [CAShapeLayer new];
        mask.frame = self.bounds;
        mask.path = _path.CGPath;
        self.layer.mask = mask;
    }
    return self;
}
- (void)setText:(NSString *)text withAlignment:(NSTextAlignment)alignment
{
    _buttonLabel = [[UILabel alloc] init];
    _buttonLabel.font = FONT_Helvetica_Neue(14);
    _buttonLabel.textColor = [UIColor whiteColor];
    _buttonLabel.text = text;
    _buttonLabel.textAlignment = alignment;
    if (alignment == NSTextAlignmentLeft) {
        _buttonLabel.frame = CGRectMake(15 + 10, 0, elementWidth(self), elementHeight(self));
    } else if (alignment == NSTextAlignmentRight) {
        _buttonLabel.frame = CGRectMake(0, 0, elementWidth(self) - 15 - 10, elementHeight(self));
    } else if (alignment == NSTextAlignmentCenter) {
        _buttonLabel.frame = CGRectMake(0, 0, elementWidth(self), elementHeight(self));
    }
    [self addSubview:_buttonLabel];
}
- (void)setBackgroundColor:(UIColor *)backgroundColor
{
    [self setImage:[Utils imageWithColor:backgroundColor andSize:self.frame.size] forState:UIControlStateNormal];
    CAShapeLayer *mask = [CAShapeLayer new];
    mask.frame = self.bounds;
    mask.path = _path.CGPath;
    self.layer.mask = mask;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint touchLocation = [touch locationInView:self];
    if ([_path containsPoint:touchLocation]) {
        NSLog(@"Inside!");
        self.highlighted = YES;
        //[self sendActionsForControlEvents:UIControlEventTouchUpInside];
    }
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint touchLocation = [touch locationInView:self];
    self.highlighted = NO;
    if ([_path containsPoint:touchLocation]) {
        [self sendActionsForControlEvents:UIControlEventTouchUpInside];
    }
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint touchLocation = [touch locationInView:self];
    if ([_path containsPoint:touchLocation]) {
        NSLog(@"...");
        self.highlighted = YES;
    }
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint touchLocation = [touch locationInView:self];
    self.highlighted = NO;
    if ([_path containsPoint:touchLocation]) {
        [self sendActionsForControlEvents:UIControlEventTouchUpInside];
    }
}

Answer 1

不要尝试实现自定义触摸事件处理，请重写hitTest:withEvent:方法。请参考本教程，我相信它描述了您的情况。这是另一个例子