UIGestureRecognizer blocking table view scrolling
I'm using a custom UIGestureRecognizer
subclass to track gestures on my InfoView
class. The InfoView
class is a subview of a custom UITableViewCell
subclass called InfoCell
.
I've added my gesture recognizer to my root view (the parent view of everything else on screen, because the purpose of my custom gesture recognizer is to allow dragging of InfoCell
views between tables). Now, everything works as it should except one thing. I'm using the following code in my UIGestureRecognizer
subclass to detect touches on the InfoView
view:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UIView *touchView = [[touches anyObject] view];
if ([touchView isKindOfClass:[InfoView class]]) {
// Do stuff
}
The problem here is that the touches on the InfoView
object are being intercepted, therefore they are not being forwarded to the UITableView
which contains the InfoCell
, which is the parent view of the Info开发者_如何学编程View
. This means that I can no longer scroll the table view by dragging on the InfoView
view, which is an issue because the InfoView
covers the entire InfoCell
.
Is there any way I can forward the touches onto the table view so that it can scroll? I've tried a bunch of things already:
[super touchesBegan:touches withEvent:event];
[touchView.superview.superview touchesBegan:touches withEvent:event];
(touchView.superview.superview
gets a reference to its parent UITableView
)
But nothing has worked so far. Also, the cancelsTouchesInView
propery of my UIGestureRecognizer
is set to NO
, so thats not interfering with the touches.
Help is appreciated. Thanks!
Check out the UIGestureRecognizerDelegate method: - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
If this returns YES it will prevent your gesture recognizer from stomping on the one that UIScrollView is using to detect scrolling.
UIGestureRecognizer has a property "cancelsTouchesInView" which is set to YES by default. This means that touches in a UIView are cancelled when a gesture is recognized. Try to set it to NO to allow the UIScrollView to receive further touch events.
I had a line in my touchesBegan
method that set the state
property of the gesture recognizer to UIGestureRecognizerStateBegan
. Removing this line seems to fix the problem.
You can try add this notification
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer {
if ([gestureRecognizer class] == [UIPanGestureRecognizer class]) {
UIPanGestureRecognizer *panGestureRec = (UIPanGestureRecognizer *)gestureRecognizer;
CGPoint point = [panGestureRec velocityInView:self];
if (fabsf(point.x) > fabsf(point.y) ) {
return YES;
}
}
return NO;
}
精彩评论