I can't seem to be able to figure out why this code for forwarding a UIButton touch stopped working in iOS5:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesBegan:touches withEvent:event];
[self.nextResponder touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesMoved:touches withEvent:event];
[self.nextResponder touchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesEnded:touches withEvent:event];
[self.nextResponder touchesEnded:touches withEvent:event];
}
When I log the next responder's touches methods I can see that touches moved is only forwarded once and touches ended isn't forward at all. This is very unexpected behavior, as all touches are forwarded in iOS4. Any help would be appreciated.
While comment posters were able to get this code to work fine in their tests, I was unsuccessful in getting it to reliably work in iOS5. My solution was to use delegation to forward the touches to the interested party. Not elegant or preferred, but so far has worked fine without any gotchas.
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My Application works on every device except some iPhone 6s. When user tries to tap on buttons nothing happens. I checked Buttons frames and everything is right but still nothing happens when user taps on buttons. I think this is something touch related. Any kind of help here will be appreciated. Thanks.
If you have used any UIButton Category and Overrides the Touch methods
then try adding:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesMoved:touches withEvent:event];
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesEnded:touches withEvent:event];
}
I have some custom animations in my UIButton subclass. I override some inner methods for starting and ending animation
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
//there is my start animation
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesEnded:touches withEvent:event];
//there is my end animation
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesCancelled:touches withEvent:event];
//there is my end animation
}
There is almost all good. All my buttons make some actions on event UIControlEventTouchUpInside. And there is my problem. Methods touchesEnded and touchesCancelled are called only after my app handle UIControlEventTouchUpInside event. So animations in button looks not so nice like I want.
So question is: can I delay UIControlEventTouchUpInside event on some ms and firstly handle touchesEnded method of my button for smooth animation?
I subclassed the UIWindow, but for some reason the - (void)sendEvent:(UIEvent *)event gets called 2 times for any interaction with the screen. Any ideas why would that happen?
For debugging purposes, subclass window (of app delegate) and override sendEvent: method
-(void) sendEvent:(UIEvent *)event
{
NSLog(#"%#",event);
[super sendEvent:event];
}
Most probably, you will notice the events responsible for TouchesBegan and TouchesEnded (for tapping). This can be tested by subclassing the View and overriding touch related methods.
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"tocuhesBegan");
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"touchesMoved");
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"touchesEnded");
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"touchesCancelled");
}
Also, try drag/swipe on the view to notice the change in count of events sent to view :)
sendEvent gets called for fingerDown and allFingersUp
I am dtecting touches on my UIView.
Is some situations I want to be abel to cancel touches so that touchesEnded won't get called. But doesn't matter what touchesEnded will always get called?
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
if (SOMETHING_SPECIAL)
{
[super touchesCancelled:touches withEvent:event];
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
//I don't want it to get here if touches were canceled how can i do this?
}
- In my touchesEnded how can I determine whether touches were canceled or not?
TouchesEnded will always get called wherever your touches where canceled or not, so I would suggest instead having that exact:
if (SOMETHING_SPECIAL)
{
}
In your:
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
To get the touchesCancelled event, implement this method from UIResponder.
touchesCancelled:withEvent:.
It seems that there is no guarantee about the order in which UITouches appear when looping through a UIGestureRecognizer's method [locationOfTouch: inView:]. Specifically:
for (int i = 0; i < [recognizer numberOfTouches]; i++) {
CGPoint point = [recognizer locationOfTouch:i inView:self];
NSLog(#"[%d]: (%.1f, %.1f)", i, point.x, point.y);
}
One would think that point with index 0 would be the first UITouch, or the first that was released, but quite often the order of 2 touches is mixed up. Does anyone know how to test for the order of those events? Unfortunately there is no access to the UITouch objects themselves (with the timestamp).
Also, no guarantee is made in the documentation that the touches from -locationOfTouch:inView: will always be in a reliable order. Can anyone confirm or deny this?
You could try setting the recognizer's delegate property and implementing -gestureRecognizer:shouldReceiveTouch:. It should be called sequentially, and you can then hold on to the touches.
It seems like to me like want to track i.e. two fingers of two hands independently, instead of recognizing a concrete gesture which is the goal of a UIGestureRecognizer, as the name says. If that's what you want i'd rather implement the UIResponder methods:
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesBegan:touches withEvent:event];
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesMoved:touches withEvent:event];
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesEnded:touches withEvent:event];
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
[self touchesEnded:touches withEvent:event];
}
With this approach you really get a set of UITouch objects und can do advanced tracking.
Why not iterating through UITouches sorted by timestamp?