I'm having a rectangle (derived from UIView). This rectangle has an attached UITapGestureRecognizer, UIPanGestureRecognizer, UIPinchGestureRecognizer and an UIRotationGestureRecognizer.
These gesture recognizers are used to move the view, zoom it and rotate it.
However there is a conflict between the recognizers since rotating doesn't work while panning and so on...
I tried the following
[self.pincher requireGestureRecognizerToFail:self.panner];
With this rotating working while panning. How to extend that such the pinching is working either?
Edit:
Whats working:
Every gesture recognizer is working on it's own. But in combination there are troubles or let's say I want a different behavior ;) If I pan an object and tap with a second finger on it and pinch, I want to zoom the object - this is not working.
However, starting rotating with the second finger works with the code line above.
The UIGestureRecognizerDelegate protocol declares the following method gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer:
You can override this method and return YES to have your recognizers working at the same time:
self.pincher.delegate = self;
self.panner.delegate = self;
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
return YES;
}
EDIT:
I've written a simple view controller that implements simultaneous scale, rotate, and pan on a UIView, you can check out this gist
Related
EDIT : Will make it clearer what I am trying to achieve.
I have some annotations on a MKMapView that I want to make easy to drag. The standard Apple way to move the annotations is to tap once then quickly tap and hold and drag. The users of the app have complained that it is too difficult to do this.
So technically what I'd like to do is to use a pan gesture. The problem is that MKMapView is also using the pan gesture to move the map about.
What I would like to do is when the use does the pan gesture, check if the pan gesture starts really close to an annotation, if so then let the pan gesture handler move the annotation. I have this part working.
But if the pan gesture was not close to an annotation then pas the gesture on to MKMapView for it to be handled by it.
// EDIT END
I've a method to handle a pan gesture. This gets called as I would expect when there is a pan gesture on the MKMapView. Sometimes I would not want to handle the gesture in my method but to pass the gesture through to the MKMapView to pan/drag the map around like normal.
Here is an outline of what I've got so far.
The pan gesture is being handled by the method:
-(void)panGesture:(UIPanGestureRecognizer*)sender
Depending on some logic I would like to pass this gesture through to the MKMapView (self.mapView).
Can anybody share the code to do this please?
I tried [self.mapView gestureRecognizerShouldBegin:sender]; but nothing happened from this call.
- (void) addPanGesture
{
self.panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(panGesture:)];
self.panGesture.delegate = self;
[self.panGesture setMinimumNumberOfTouches:1];
[self.panGesture setMaximumNumberOfTouches:1];
[self.mapView addGestureRecognizer:self.panGesture];
}
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return YES;
}
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
BOOL result = NO;
if ((gestureRecognizer == self.panGesture) && [[otherGestureRecognizer view] isDescendantOfView:[gestureRecognizer view]])
{
result = YES;
}
return result;
}
-(void)panGesture:(UIPanGestureRecognizer*)sender
{
//some logic to see if we will handle the gesture in this method or pass gesture on to the MKMapView
return;
}
The standard Apple way to move the annotations is to tap once then quickly tap and hold and drag. The users of the app have complained that it is too difficult to do this.
I'm not think so.. :(
I'm going to write my logic, Actually It is bad thing to use pan gesture even apple provide default drag and drop facility. BTW if you are going with your way that mentioned in your question then you must need to add separate pan gesture for each and every annotation those are displaying on the map. Add it's own tag and keep same name of gesture method for all so you will easily mange it by tag. so when end-user will tap/touch on any annotation then it's method will be called and you can get touched/tapped annotation by it's own tag. write your code for drag-drop annotation only. Not sure but might be solve your problem.
I agree completely with iPatel: If possible one should use the standard Apple way, since users are used to it.
But if you really want to implement you own solution, maybe the following might work (not tested):
The MapView has a built-in PanGestureRecognizer (called here builInPGR). I assume you added your own PanGestureRecognizer (called here ownPGR) to this MapView.
Now the following function in the UIGestureRecognizerDelegate protocol controls if two gesture recognisers should recognise simultaneously (see the docs):
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer,
shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool
The default implementation returns false.
You mentioned that you can drag your annotations using ownPGR. This means that builInPGR does not recognise the pan gesture simultaneously with ownPGR.
If you implement now this delegate function and return true, ownPGR and builInPGR should work simultaneously: builInPGR would move the map, and ownPGR would check, if a region close to an annotation has been tapped, and if so, would move the annotation.
Now, this delegate function gives you also a pointer to builInPGR, the otherGestureRecognizer.
So if ownPGR decides to drag an annotation since it started close to it, you can set the property isEnabled of builInPGR to false. This lets builInPGR transition to a cancelled state, and the map would no longer be dragged.
Of course, you had to set builInPGR.isEnabled to true again, when ownPGR finishes dragging the annotation.
Once more: I don’t know if this works, but it might. And I strongly recommend to use the standard approach!
EDIT: I am sorry, I just realised that you wanted the answer in Obj-C. But, using the docs (just switch to Obj-C) it should be easy to test it in Obj-C.
So I'm working on an app at work where a majority of the code written has been written by other people. So I have a class called BaseDetailViewController and another class which subclasses BaseDetailViewController called ProductViewController. I have a pinch recognizer on ProductViewController and there is a pinch recognizer on it's parent BaseDetailViewController. It seems like the recognizer on the parent seems to be overriding the recognizer on ProductViewController. When I comment out the one on the parent then the recognizer on the child works just fine.
I tried using:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
return TRUE;
}
with proper delegation to see if that helped but the recognizer on BaseDetailViewController seems to take the bacon every time.
What do I need to do to get the one on ProductViewController firing?
It means you are trying to have two Pinch gesture recognizers on the same view. When you are adding pinch gesture recognizer in ProductViewController, try to invalidate pinch gesture recognizer in BaseDetailViewController. It should solve the problem.
UITapGestureRecognizer is applied to both UIImageView and its subview (UITextView). However, when I tap on subview, the receiver becomes subview and its parent view (i.e. UIImageView + UITextView). It should however be only subview because that was the one I tapped. I was assuming nested gestures would react first but apparently parent receives the fist tap and then it goes to child.
So, there are different solutions out there for various scenarios (not similar to mine but rather buttons inside scroll view conflict). How can I easily fix my issue without possible subclassing and for iOS 6+ support? I tried delaying touch on start for UIGestureRecognizer on UIImageView and I tried setting cancelsTouchesInView to NO - all with no luck.
Try the following code:
conform the <UIGestureRecognizerDelegate> to your class.
set yourGesture.delegate = self;
then add this delegate Method:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
// return YES (the default) to allow the gesture recognizer to examine the touch object, NO to prevent the gesture recognizer from seeing this touch object.
if([touch.view isKindOfClass: [UITextView class]] == YES)] {
return YES;
}
else {
return NO;
}
}
Hope it will solve your issue. Enjoy Coding..!!!!
That's exactly what is it supposed to do.
View hierarchy is like a tree structure and its traversal during a touch gesture starts from the root node. It is very likely for your parent view to receive gesture first and then its subviews. The traversal skips the nodes for which
userInteractionEnabled = NO.
since, you don't have any code I can't help you to play with this flag. A more general solution is to always set gesture only for your parentView and in the gesture delegates check the coordinates if it belongs to any one of the subview and if yes then call your gesture method for your subview.
Not a clean approach but works. !!
you should implement the UIGestureRecognizer delegate methods and apply the correct policy to the gesture, when multiple gesture are recognized
I have a map drawn with OpenGLES, and I have a pan gesture recognizer that has maximumNumberofTouches set to 1 to pan around the map and a pinch gesture recognizer for zooming. I want to start panning once im done zooming, (one finger is lifted off the screen) but the pan gesture recognizer doesnt kick in until pinchgesturerecognizer is done which is when it detects there are no fingers on the screen. Any ideas?
It may be possible to allow both gestures to be active via the delegate method:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer
shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
// The two recognizers using the delegate (scale and rotate) should both be active.
//
return YES;
}
And keep a BOOL that tracks if the user is zooming, not allowing the code in the pan gesture to execute while that BOOL is YES. Altering the BOOL value by checking the number of touches in the touchesMoved:withEvent method (or perhaps some other UIGestureRegonizer method).
I think this should work, I do something similar in an app that allows scaling, rotating, and dragging, where dragging is only allowed when the user isn't scaling/rotating.
~Good Luck
I need have a view where users can draw multiple rectangles. Now I need to be able to move those rectangles using a Pan gesture. The problem I am having is that I can move any single rectangle with the Pan gesture recognizer with no problem. Now when I use 2 fingers to Pan 2 rectangles to move simultaneously it doesn't work.
Seem to me that the problem is the target/action that I specified for the pan gesture gets fired only once.
My view adopts the UIGestureRecognizerDelegate and has defined this delegate method:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return YES;
}
Thanks in advance!
Add gesture recognizer to each created rectangle view individually by making a method.
like this
- (void)addGestureRecognizersToPiece:(UIView *)piece
{
// Add the gesture recognizer to the piece here
}
You can loop in to add the gesture recognizer to all the pieces simultaneously, or while u create each rectangle, just fire this method after creating the rectangle, and passing that as the piece parameter to this function.
That should help.