UIButton超出UIView边界不可点击

当按钮超过了父视图范围，点击是没有反应的。因为消息的传递是从最下层的父视图开始调用hittest方法。
- (UIView )hitTest:(CGPoint)point withEvent:(UIEvent )event {
UIView *view = [super hitTest:point withEvent:event];
return view;
}
当存在view时才会传递对应的event，现在点击了父视图以外的范围，自然返回的是nil。所以当子视图（比如按钮btn）因为一些原因超出了父视图范围，就要重写hittest方法，让其返回对应的子视图，来接收事件。
- (UIView )hitTest:(CGPoint)point withEvent:(UIEvent )event {
UIView *view = [super hitTest:point withEvent:event];
if (view == nil) {
CGPoint tempoint = [btn convertPoint:point fromView:self];
if (CGRectContainsPoint(btn.bounds, tempoint))
{
view = btn;
}
}
return view;
}
或

• (UIView )hitTest:(CGPoint)point withEvent:(UIEvent )event { UIView *result = [super hitTest:point withEvent:event]; CGPoint buttonPoint = [self.button convertPoint:point fromView:self]; if ([self.button pointInside:buttonPoint withEvent:event]) { return self.button; } return result; }