UISwipeGestureRecognizer UIGestureRecognizerStateChanged not called - ios

I'm define two UISwipeGestureRecognizer in my application:
UISwipeGestureRecognizer *swipeLeftVolume = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeGestureVolume:)];
swipeLeftVolume.direction = UISwipeGestureRecognizerDirectionLeft;
[self.playerView addGestureRecognizer:swipeLeftVolume];
UISwipeGestureRecognizer *swipeRightVolume = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeGestureVolume:)];
swipeRightVolume.direction = UISwipeGestureRecognizerDirectionRight;
[self.playerView addGestureRecognizer:swipeRightVolume];
In the target method i have 3 states:
UIGestureRecognizerStateBegan
UIGestureRecognizerStateChanged
UIGestureRecognizerStateEnded
and i noticed that only the UIGestureRecognizerStateEnded is called.
Any idea what can be the problem? i want to recognize a swipe on specific UIView :
- (void)handleSwipeGestureVolume:(UISwipeGestureRecognizer *)sender {
if (sender.state == UIGestureRecognizerStateBegan) {
NSLog(#"Start");
} else if (sender.state == UIGestureRecognizerStateChanged) {
NSLog(#"Changed");
} else if (sender.state == UIGestureRecognizerStateEnded) {
NSLog(#"Finish");
}
}

Seem like you are confused between UISwipeGestureRecognizer and UIPanGestureRecognizer.
UISwipeGestureRecognizer will generate UIGestureRecognizerStateEnded state only while UIPanGestureRecognizer has both 3 states you want.
If you need to receive both UIGestureRecognizerStateBegan, UIGestureRecognizerStateChanged, UIGestureRecognizerStateEnded, use UIPanGestureRecognizer instead.
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeGestureVolume:)];
[self.playerView addGestureRecognizer:panGesture];

Make sure you enable UserInteraction for self.playerView.

For any gesture recogniser, user interaction must be enabled to work. Without it none of the gestures will be triggered including touchBegan:, touchMove:, etc.
so you need to make [self.playerView setUserInteractionEnabled:TRUE];
And one more thing I would like to let you know that if you have implemented touchBegan:, touchMove:, etc. then the method will be triggered first for gesture rather than UIGestureRecognizer shilds.

Related

how can check that which uiimageview is presently clicked?

I have three UIImageview. I set the action for UIImageview by using tapGesture. I want each UIImageview to have a different action. How can I check that which UIImageview is presently clicked?
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(singleTapping:)];
[singleTap setNumberOfTapsRequired:1];
[_imageOne addGestureRecognizer:singleTap];
[_imageTwo addGestureRecognizer:singleTap];
[_imageThree addGestureRecognizer:singleTap];
-(void)singleTapping:(UIGestureRecognizer *)recognizer {
}
You can detect using below code:
-(void)singleTapping:(UITapGestureRecognizer *) recognizer{
if (recognizer.view == _imageOne){
} else if (recognizer.view == _imageTwo) {
}else
{
}
}
A UIGestureRecognizer is to be used with a single view. There is this explicit information in the Apple documentation:
Gesture Recognizers Are Attached to a View
Every gesture recognizer is associated with one view. By contrast, a
view can have multiple gesture recognizers, because a single view
might respond to many different gestures. For a gesture recognizer to
recognize touches that occur in a particular view, you must attach the
gesture recognizer to that view.
Firstly, you can't attach same UITapGestureRecognizer to more than one view.
So, your code will not work and you have to create three UITapGestureRecognizer instances and have to attach it to views like below:
UITapGestureRecognizer *singleTapImg1 = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(singleTapping:)];
[singleTapImg1 setNumberOfTapsRequired:1];
UITapGestureRecognizer *singleTapImg2 = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(singleTapping:)];
[singleTapImg2 setNumberOfTapsRequired:1];
UITapGestureRecognizer *singleTapImg3 = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(singleTapping:)];
[singleTapImg3 setNumberOfTapsRequired:1];
[_imageOne addGestureRecognizer:singleTapImg1];
[_imageTwo addGestureRecognizer:singleTapImg2];
[_imageThree addGestureRecognizer:singleTapImg3];
Now, you can use below code to get, which imageview clicked and perform action according to that:
-(void)singleTapping:(UIGestureRecognizer *)recognizer {
if (recognizer.view == _imageOne){
//_imageOne tapped
}
else if (recognizer.view == _imageTwo) {
//_imageTwo tapped
}else{
//_imageThree tapped
}
}

How to implement Swipe and Hold gesture recognizer in Objective-C?

I am working on an application which works like a remote control of different devices like Game Console, Set-top Box, etc.
Application contains different type of controls like gesture and buttons to perform events as remote.
Single gesture view contains multiple gesture recognizer as follow:
1 finger Tap using UITapGestureRecognizer
2 finger Tap using UITapGestureRecognizer
1 finger swipe using UISwipeGestureRecognizer
2 finger swipe using UISwipeGestureRecognizer
My requirement is to implement 1 finger Swipe gesture recognizer along with hold event. So, that will continue my swipe action until user will not remove its finger from the view.
I have tried UILongPressGestureRecognizer after UISwipeGestureRecognizer but this didn’t work for me because it is executing along with Swipe movement. And I want this after Swipe end, but finger will not remove.
My code snippet :
-(void) gestureView:(UIView*)viewGesture {
UISwipeGestureRecognizer *swipeGestureSingleRight;
UISwipeGestureRecognizer *swipeGestureSingleLeft;
UISwipeGestureRecognizer *swipeGestureSingleUp;
UISwipeGestureRecognizer *swipeGestureSingleDown;
swipeGestureSingleUp = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(swipeGestureSingle_Handle:)];
[swipeGestureSingleUp setDelegate:self];
[swipeGestureSingleUp setDirection:(UISwipeGestureRecognizerDirectionUp)];
[swipeGestureSingleUp setNumberOfTouchesRequired:1];
[viewGesture addGestureRecognizer:swipeGestureSingleUp];
swipeGestureSingleDown = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(swipeGestureSingle_Handle:)];
[swipeGestureSingleDown setDelegate:self];
[swipeGestureSingleDown setDirection:(UISwipeGestureRecognizerDirectionDown)];
[swipeGestureSingleDown setNumberOfTouchesRequired:1];
[viewGesture addGestureRecognizer:swipeGestureSingleDown];
swipeGestureSingleRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(swipeGestureSingle_Handle:)];
[swipeGestureSingleRight setDelegate:self];
[swipeGestureSingleRight setDirection:(UISwipeGestureRecognizerDirectionRight)];
[swipeGestureSingleRight setNumberOfTouchesRequired:1];
[viewGesture addGestureRecognizer:swipeGestureSingleRight];
swipeGestureSingleLeft = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(swipeGestureSingle_Handle:)];
[swipeGestureSingleLeft setDelegate:self];
[swipeGestureSingleLeft setDirection:(UISwipeGestureRecognizerDirectionLeft)];
[swipeGestureSingleLeft setNumberOfTouchesRequired:1];
[viewGesture addGestureRecognizer:swipeGestureSingleLeft];
longPressGestureOnSwipe = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(longPressGesture_Handle:)];
longPressGestureOnSwipe.minimumPressDuration = 0.03;
longPressGestureOnSwipe.delegate = self;
[viewGesture addGestureRecognizer:longPressGestureOnSwipe];
isSwipeEnd = false;
[longPressGestureOnSwipe setEnabled:isSwipeEnd];
}
- (void)swipeGestureSingle_Handle:(UISwipeGestureRecognizer*)sender {
if (sender.state == UIGestureRecognizerStateEnded) {
singleTouchSwipeSenderDirection = sender.direction;
isSwipeEnd = true;
[longPressGestureOnSwipe setEnabled:isSwipeEnd];
}
}
-(void)longPressGesture_Handle:(UILongPressGestureRecognizer*)sender {
if (sender.state == UIGestureRecognizerStateEnded) {
isSwipeEnd = false;
[longPressGestureOnSwipe setEnabled:isSwipeEnd];
}
}
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
return YES;
}
- (void)touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event {
if (isSwipeEnd) {
[super touchesBegan:touches withEvent:event];
} else {
return;
}
}
Please suggest me correction or solution for my requirement.
Thanks in advance!

Adding both short long gestures in same view with proper differentiation

I am working on app in which I want both short long gesture in same view, I added but issue is I'm facing is that short gesture end always call, Need your help how to do that in right way. Below is my code.
UILongPressGestureRecognizer *longGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(longGestureOnFormFields:)];
longGesture.minimumPressDuration = 1.0f;
[longGesture setDelegate:self];
[self addGestureRecognizer:longGesture];
UILongPressGestureRecognizer *shortGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(shortGesture:)];
shortGesture.minimumPressDuration = 0.1f;
[shortGesture setDelegate:self];
[self addGestureRecognizer:shortGesture];
- (void)longGestureOnFormFields:(UIGestureRecognizer*) recogniser
{
if (recogniser.state == UIGestureRecognizerStateEnded ) {
}
- (void)shortGesture:(UIGestureRecognizer*) recogniser
{
if (recogniser.state == UIGestureRecognizerStateEnded ) {
}
You can manage that by using one UITapGestureRecognizer like,
self.view.userInteractionEnabled = YES;
UILongPressGestureRecognizer *longGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(longGestureOnFormFields:)];
longGesture.minimumPressDuration = 1.0f;
[longGesture setDelegate:self];
[self.view addGestureRecognizer:longGesture];
UITapGestureRecognizer *recog = [[UITapGestureRecognizer alloc]initWithTarget:self action:#selector(testm)];
[self.view addGestureRecognizer:recog];
and your methods smething like,
-(void)testm{
NSLog(#"tap");
}
-(void)longGestureOnFormFields : (UILongPressGestureRecognizer*)sender{
if (sender.state == UIGestureRecognizerStateEnded ) {
NSLog(#"long press gesture");
}
}
I have added gesture recognizer in viewDidload i.e in viewcontroller so i have add it to self.view if you have subclass UIVIew and adding this to that view then add it on self like [self addgesture...] as shown in question!

IOS: UISwipeGestureRecognizer

I have this code:
UISwipeGestureRecognizer *recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(rightSwipeHandle:)];
[recognizer setNumberOfTouchesRequired:1];
[n16 addGestureRecognizer:recognizer];
[n17 addGestureRecognizer:recognizer];
- (void)rightSwipeHandle:(UISwipeGestureRecognizer*)gestureRecognizer{
NSLog(#"SWIPE");
}
How can I know what view happens gesture? views are n16 and n17
I am not sure if you can register the same UIGestureRecognizer instance to different views, but if you could, I think UIGestureRecognizer.view property is what you are looking for.
http://developer.apple.com/library/ios/#documentation/UIKit/Reference/UIGestureRecognizer_Class/Reference/Reference.html#//apple_ref/occ/cl/UIGestureRecognizer
So, you should be able to do something like this. (again, I am not sure if you can attach different UIGestureRecognizer instance to different views...)
- (void)rightSwipeHandle:(UISwipeGestureRecognizer*)gestureRecognizer{
if(gestureRecognizer.view == n16)
{
// specific operation to n16
}
else if(gestureRecognizer.view == n17)
{
// specific operation to n17
}
}
Like this:
- (void)rightSwipeHandle:(UISwipeGestureRecognizer*)gestureRecognizer {
NSLog(#"SWIPE");
UIView *vw = [gestureRecognizer view]; // this is the view that generated the
// gesture - either n16 or n17
}

Setting direction for UISwipeGestureRecognizer

I want to add simple swipe gesture recognition to my view based iPhone project. Gestures in all directions (right, down, left, up) should be recognized.
It is stated in the docs for UISwipeGestureRecognizer:
You may specify multiple directions by specifying multiple UISwipeGestureRecognizerDirection constants using bitwise-OR operands. The default direction is UISwipeGestureRecognizerDirectionRight.
However for me it doesn't work. When all four directions are OR'ed only left and right swipes are recognized.
- (void)viewDidLoad {
UISwipeGestureRecognizer *recognizer;
recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeFrom:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionRight | UISwipeGestureRecognizerDirectionDown | UISwipeGestureRecognizerDirectionLeft | UISwipeGestureRecognizerDirectionUp)];
[[self view] addGestureRecognizer:recognizer];
[recognizer release];
[super viewDidLoad];
}
-(void)handleSwipeFrom:(UISwipeGestureRecognizer *)recognizer {
NSLog(#"Swipe received.");
}
I fixed this with adding four recognizers to the view but I'm curious to know why didn't it work as advertised in docs?
- (void)viewDidLoad {
UISwipeGestureRecognizer *recognizer;
recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeFrom:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionRight)];
[[self view] addGestureRecognizer:recognizer];
[recognizer release];
recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeFrom:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionUp)];
[[self view] addGestureRecognizer:recognizer];
[recognizer release];
recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeFrom:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionDown)];
[[self view] addGestureRecognizer:recognizer];
[recognizer release];
recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeFrom:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionLeft)];
[[self view] addGestureRecognizer:recognizer];
[recognizer release];
[super viewDidLoad];
}
-(void)handleSwipeFrom:(UISwipeGestureRecognizer *)recognizer {
NSLog(#"Swipe received.");
}
Seems like there is a bug. You can specify the allowed direction(s) as you did. But when you try to access the actual direction that triggered the swipe in the action selector method you still get the bit mask you originally set (for the allowed directions).
This means that checks for the actual direction will always fail when more than 1 direction is allowed.
You can see it for yourself quite easily when you output the value of 'direction' in the selector method (ie -(void)scrollViewSwiped:(UISwipeGestureRecognizer *)recognizer).
Filed a bug report (#8276386) to Apple.
[Update] I got an answer from Apple saying that the behavior works as was intended.
So for example in a table view you can swipe left or right in a table view cell to trigger 'delete' (this would have directions of the swipe gesture set to left and right)
This means that the original workaround is the way it's supposed to be used. The direction property can only be used to get the gestures recognized correctly, but not in the method performed on a successful recognition to compare for the actual direction that triggered the recognition.
I noticed that left/right and up/down gestures work together in pairs, so you only need to specify two gesture recognizers. And the docs do seem to be wrong.
Well that sucks, I solved the problem by adding 2 gestures like Lars mentioned and that worked perfectly...
1) Left/Right
2) Up/Down
UISwipeGestureRecognizer *swipeLeftRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleGesture:)];
[swipeLeftRight setDirection:(UISwipeGestureRecognizerDirectionRight | UISwipeGestureRecognizerDirectionLeft )];
[self.view addGestureRecognizer:swipeLeftRight];
UISwipeGestureRecognizer *swipeUpDown = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleGesture:)];
[swipeUpDown setDirection:(UISwipeGestureRecognizerDirectionUp | UISwipeGestureRecognizerDirectionDown )];
[self.view addGestureRecognizer:swipeUpDown];
UISwipeGestureRecognizer *recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(didSwipe:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionRight)];
[self.view addGestureRecognizer:recognizer];
[recognizer release];
recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(didSwipe:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionLeft)];
[self.view addGestureRecognizer:recognizer];
[recognizer release];
Now this is the didSwipe function
- (void) didSwipe:(UISwipeGestureRecognizer *)recognizer{
if([recognizer direction] == UISwipeGestureRecognizerDirectionLeft){
//Swipe from right to left
//Do your functions here
}else{
//Swipe from left to right
//Do your functions here
}
}
If your using Xcode 4.2 you can add Gesture Recognizers # the storyboard and then link the GUI Gesture Recognizers to IBActions.
You can find the Gesture Recognizers in the Object Library of the Utility Pane (The bottom of the Right pane).
Then its just a matter of Control-dragging to the appropriate action.
If you want it to detect all four directions, you'll need to create four instances, as you did in your work-around.
Here's Why:
The same instance of UISwipeGestureRecognizer that you create is the instance that gets passed to the selector as sender. So if you set it to recognize all four directions, it will return true for sgr.direction == xxx where xxx is any one of the four directions.
Here's an alternative work-around that involves less code (assumes ARC use):
for(int d = UISwipeGestureRecognizerDirectionRight; d <= UISwipeGestureRecognizerDirectionDown; d = d*2) {
UISwipeGestureRecognizer *sgr = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeFrom:)];
sgr.direction = d;
[self.view addGestureRecognizer:sgr];
}
Swift 2.1
I had to use the following
for var x in [
UISwipeGestureRecognizerDirection.Left,
UISwipeGestureRecognizerDirection.Right,
UISwipeGestureRecognizerDirection.Up,
UISwipeGestureRecognizerDirection.Down
] {
let r = UISwipeGestureRecognizer(target: self, action: "swipe:")
r.direction = x
self.view.addGestureRecognizer(r)
}
Here is a code sample for UISwipeGestureRecognizer usage. Note comments.
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
//add gesture recognizer. The 'direction' property of UISwipeGestureRecognizer only sets the allowable directions. It does not return to the user the direction that was actaully swiped. Must set up separate gesture recognizers to handle the specific directions for which I want an outcome.
UISwipeGestureRecognizer *gestureRight;
UISwipeGestureRecognizer *gestureLeft;
gestureRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(swipeRight:)];//direction is set by default.
gestureLeft = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(swipeLeft:)];//need to set direction.
[gestureLeft setDirection:(UISwipeGestureRecognizerDirectionLeft)];
//[gesture setNumberOfTouchesRequired:1];//default is 1
[[self view] addGestureRecognizer:gestureRight];//this gets things rolling.
[[self view] addGestureRecognizer:gestureLeft];//this gets things rolling.
}
swipeRight and swipeLeft are methods that you use to perform specific activities based on left or right swiping. For example:
- (void)swipeRight:(UISwipeGestureRecognizer *)gesture
{
NSLog(#"Right Swipe received.");//Lets you know this method was called by gesture recognizer.
NSLog(#"Direction is: %i", gesture.direction);//Lets you know the numeric value of the gesture direction for confirmation (1=right).
//only interested in gesture if gesture state == changed or ended (From Paul Hegarty # standford U
if ((gesture.state == UIGestureRecognizerStateChanged) ||
(gesture.state == UIGestureRecognizerStateEnded)) {
//do something for a right swipe gesture.
}
}
UISwipeGestureRecognizer *Updown=[[UISwipeGestureRecognizer alloc]initWithTarget:self action:#selector(handleGestureNext:)];
Updown.delegate=self;
[Updown setDirection:UISwipeGestureRecognizerDirectionDown | UISwipeGestureRecognizerDirectionUp];
[overLayView addGestureRecognizer:Updown];
UISwipeGestureRecognizer *LeftRight=[[UISwipeGestureRecognizer alloc]initWithTarget:self action:#selector(handleGestureNext:)];
LeftRight.delegate=self;
[LeftRight setDirection:UISwipeGestureRecognizerDirectionLeft | UISwipeGestureRecognizerDirectionRight];
[overLayView addGestureRecognizer:LeftRight];
overLayView.userInteractionEnabled=NO;
-(void)handleGestureNext:(UISwipeGestureRecognizer *)recognizer
{
NSLog(#"Swipe Recevied");
//Left
//Right
//Top
//Bottom
}
hmm, strange, it works perfect for me, I do exactly same thing
think you should try look at
UIGestureRecognizerDelegate method
- (BOOL)gestureRecognizerShouldBegin:(UISwipeGestureRecognizer *)gestureRecognizer {
// also try to look what's wrong with gesture
NSLog(#"should began gesture %#", gestureRecognizer);
return YES;
}
in logs you must see something like:
should began gesture ; target= <(action=actionForUpDownSwipeGestureRecognizer:, target=)>; direction = up,down,left,right>
use this, it should be the bit operation
gesture.direction & UISwipeGestureRecognizerDirectionUp ||
gesture.direction & UISwipeGestureRecognizerDirectionDown
This was driving me crazy. I finally figured out a reliable way to have multiple swipeGestureRecognizers.
It appears there is a bug in iOS if the name of your "action" selector is the same across multiple swipeGestureRecognizers. If you just name them differently, e.g. handleLeftSwipeFrom and handleRightSwipeFrom, everything works.
UISwipeGestureRecognizer *recognizer;
recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleLeftSwipeFrom:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionLeft)];
[[self view] addGestureRecognizer:recognizer];
[recognizer release];
recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleRightSwipeFrom:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionRight)];
[[self view] addGestureRecognizer:recognizer];
[recognizer release];

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