I am new in IOS Dev, was searching onclick event for UIView and i found this code that worked perfectly. But it doesnt call specific UIView as i am using multiple UIViews and want to add event on all of them separately while this code calls handleSingleTap onclick of either UIView. plz help..
- (void)viewDidLoad
{
[super viewDidLoad];
UITapGestureRecognizer *singleFingerTap =
[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
[self.view addGestureRecognizer:singleFingerTap];
}
- (void)handleSingleTap:(UITapGestureRecognizer *)recognizer {
CGPoint location = [recognizer locationInView:[recognizer.view superview]];
NSLog(#"Clicked");
}
You can create UITapGestureRecognizer and add it to the views you want it to be clicked.
You can also set up tag property on each view to find out which view was clicked.
For example:
UITapGestureRecognizer *singleFingerTap1 =
[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
view1.tag = 1;
[view1 addGestureRecognizer:singleFingerTap1];
UITapGestureRecognizer *singleFingerTap2 =
[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
view2.tag = 2;
[view2 addGestureRecognizer:singleFingerTap2];
//..and so on
- (void)handleSingleTap:(UITapGestureRecognizer *)recognizer {
UIView *viewClicked = recognizer.view;
NSLog(#"Clicked: %d", viewClicked.tag);
}
The other solution is add one gesture recogniser to the main view (the view which hold the others view, something as you posted) and in handleSingleTap: method check if the point is inside the view:
BOOL isPointInsideView1 = [view1 pointInside:location withEvent:nil];
BOOL isPointInsideView2 = [view1 pointInside:location withEvent:nil];
But ic can failed when one view override another.
Related
I added tapGesture for self.view and UILabel (subview of mainView), each performs different selectors.
But the only main view tapGesture is being called and label tapgesture is not being called. How it is handled?
Here is the code:
UITapGestureRecognizer *tapGesForSelf = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapGesForSelf:)];
[self.view addGestureRecognizer:tapGesForSelf];
UITapGestureRecognizer *tapLblClick = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapGesForLbl:)];
[lbl addGestureRecognizer:tapLblClick];
For two selectors only one method is called tapGesForSelf.
Here lbl is the subview of self.view.
Try this
- (void)viewDidLoad {
[super viewDidLoad];
[_lbl setUserInteractionEnabled:YES];
UITapGestureRecognizer *tapGesForSelf = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapGesForSelf:)];
[self.view addGestureRecognizer:tapGesForSelf];
UITapGestureRecognizer *tapLblClick = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapGesForLbl:)];
[_lbl addGestureRecognizer:tapLblClick];
[tapGesForSelf requireGestureRecognizerToFail:tapLblClick];
}
- (void)tapGesForSelf:(UITapGestureRecognizer *)gesture
{
NSLog(#"self");
}
- (void)tapGesForLbl:(UITapGestureRecognizer *)gesture
{
NSLog(#"label");
}
I post answer for your question now once I tried and it worked well.
First see the label in design.I set label text as "Tap Me"
Now I set the code for view and label
- (void)viewDidLoad
{
[super viewDidLoad];
//TapGesture for Label
UITapGestureRecognizer *tapLabel = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(actionTapLabel:)];
tapLabel.delegate = self;
tapLabel.numberOfTapsRequired = 1;
lblTapMe.userInteractionEnabled = YES;
[lblTapMe addGestureRecognizer:tapLabel];
//TapGesture for View
UITapGestureRecognizer *tapMainView = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(actionTapMainView:)];
tapMainView.delegate = self;
tapMainView.numberOfTapsRequired = 1;
[self.view addGestureRecognizer:tapMainView];
}
//Action method for Label
-(void)actionTapLabel:(UITapGestureRecognizer *)gestureOnLabel{
UILabel *label = (UILabel *)gestureOnLabel.view;
NSLog(#"Lable text is - %#",label.text);
}
//Action method for View
-(void)actionTapMainView:(UITapGestureRecognizer *)gestureOnMainView{
NSLog(#"The Main view is tapped");
}
Output Screenshot
Please setUserInteractionEnabled:YES for interact the TapGesture
[lbl setUserInteractionEnabled:YES];
I have a view controller with 3 UIWebViews, all with the same frame overlaying each other. I use three buttons to switch between them (similar to a segment control). I want to attach a tap gesture recognizer to the webview so that tapping each webview leads to a new controller. However, only the UITapGestureRecognizer for the first webview fires. Can anyone tell me how to get the other two gesture recognizers to fire? This is my code:
- (IBAction)changeWebView:(id)sender
{
UIButton *button = (UIButton *)sender;
switch (button.tag) {
case 0:
{
[self.view bringSubviewToFront:WebView1];
for (UITapGestureRecognizer *recognizer in WebView2.gestureRecognizers) {
[WebView2 removeGestureRecognizer:recognizer];
}
for (UITapGestureRecognizer *recognizer in WebView3.gestureRecognizers) {
[WebView3 removeGestureRecognizer:recognizer];
}
UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(showFullScreen1)];
tapGestureRecognizer.delegate = self;
[WebView1 addGestureRecognizer:tapGestureRecognizer];
}
break;
case 1:
{
[self.view bringSubviewToFront:WebView2];
for (UITapGestureRecognizer *recognizer in WebView1.gestureRecognizers) {
[WebView1 removeGestureRecognizer:recognizer];
}
for (UITapGestureRecognizer *recognizer in WebView3.gestureRecognizers) {
[WebView3 removeGestureRecognizer:recognizer];
}
UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(showFullScreen2)];
tapGestureRecognizer.delegate = self;
[WebView2 addGestureRecognizer:tapGestureRecognizer];
}
break;
case 2:
{
[self.view bringSubviewToFront:WebView3];
for (UITapGestureRecognizer *recognizer in WebView1.gestureRecognizers) {
[WebView1 removeGestureRecognizer:recognizer];
}
for (UITapGestureRecognizer *recognizer in WebView2.gestureRecognizers) {
[WebView2 removeGestureRecognizer:recognizer];
}
UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(showFullScreen3)];
tapGestureRecognizer.delegate = self;
[WebView3 addGestureRecognizer:tapGestureRecognizer];
}
break;
default:
break;
}
}
This sounds like a design issue. Why don't you only have one one UIView and render the correct content depending on what button was pressed. You can then have only one gesture recognizer that will load the proper controller (or perform the correct segue) also depending on the button.
Add UITapGestureRecognizer to a a view and add all 3 UIWebview as a subview on them.Than whenever you detect UITapGestureRecognizer to be tapped get the tag from segmentedController or button whatever you are using and find which one was tapped.
Don't add UITapGestureRecognizer and remove it again and again.
In my app, I have an image and a UITextView.
I have created a UITapGestureRecognizer for both the views but the issue is that wherever I click on the screen, only the method associated with the UITextView gets executed.
Even if I click on the image, only the UITapGestureRecognizer method associated with the UITextView gets executed.
Following is the code I've implemented:
UITapGestureRecognizer *tapGestureRecognizerImage = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(handleTapFromImage:)];
[infobutton addGestureRecognizer:tapGestureRecognizerImage];
[[self view] addGestureRecognizer:tapGestureRecognizerImage];
UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(handleTapFrom:)];
[messageOne addGestureRecognizer:tapGestureRecognizer];
[[self view] addGestureRecognizer:tapGestureRecognizer];
//The following are the methods associated
- (void) handleTapFrom: (UITapGestureRecognizer *)recognizer {
//Code to handle the gesture
NSLog(#"I am in handleTapFrom method");
}
- (void) handleTapFromImage: (UITapGestureRecognizer *)recognizer {
//Code to handle the gesture
NSLog(#"I am in handleTapFrom Image method");
[self.view makeToast:#"Your verification code does not match. Re-enter your verification code"];
}
I am sure I am missing something here.
The association in storyboard is correct to my knowledge.
Please correct me where I am going wrong
Thanks for your time
You should not add gesture on self.view.
It should get added on the view for which you want to identify tap event.
You are setting both the Tap Gesture Objects on [self view] object.
Also, the UIImageView object, lets call it imageObj, should have userInteractionEnabled = YES.
instead of:
[[self view] addGestureRecognizer:tapGestureRecognizerImage];
you should do:
[imageObj setUserInteractionEnabled:YES];
[imageObj addGestureRecognizer:tapGestureRecognizerImage];
You generally use -addGestureRecognizer: on the object you want your gesture object to work on.
Say you have a UITapGestureRecognizer object called myTapGesture.
Then, to make it work...
on a UILabel *lblSomeObj it will be:
[lblSomeObj addGestureRecognizer:myTapGesture];
on a UIView *vwSomeObj it will be:
[vwSomeObj addGestureRecognizer:myTapGesture];
etc...
Just add the gesture in the respective views and not in self.view.
UITapGestureRecognizer *tapGestureRecognizerImage = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTapFromImage:)];
[infobutton addGestureRecognizer:tapGestureRecognizerImage];
UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTapFrom:)];
[messageOne addGestureRecognizer:tapGestureRecognizer];
Add gesture on UIImageView object and make sure that image view userInteractionEnabled is set to YES
imageObj.userInteractionEnabled = YES;
[imageObj addGestureRecognizer:tapGestureRecognizerImage];
You need to include this piece of code:-
[tapGestureRecognizerImage requireGestureRecognizerToFail:tapGestureRecognizer];
[imageObj addGestureRecognizer:tapGestureRecognizerImage];
Something strange I encountered today while attaching same gesture recogniser to multiple image views. It gets attached to only the last one, in other words, it can be attached to only one view!
I had to create multiple gesture recognisers to meet my requirements.
Following is what I have done. Am I doing correct? Is that's the only way to attach recognisers to the multiple imageviews?
Please note that I don't want to use UITableView or UIVIew and put all imageviews in it and attach gesture recogniser to only UITableView or UIVIew. I have all image scattered and I have to detect which image is being dragged. Thanks.
[imgView1 setUserInteractionEnabled:YES];
[imgView1 setMultipleTouchEnabled:YES];
[imgView2 setUserInteractionEnabled:YES];
[imgView2 setMultipleTouchEnabled:YES];
[imgView3 setUserInteractionEnabled:YES];
[imgView3 setMultipleTouchEnabled:YES];
[imgView4 setUserInteractionEnabled:YES];
[imgView4 setMultipleTouchEnabled:YES];
[imgView5 setUserInteractionEnabled:YES];
[imgView5 setMultipleTouchEnabled:YES];
[imgView6 setUserInteractionEnabled:YES];
[imgView6 setMultipleTouchEnabled:YES];
//Attach gesture recognizer to each imagviews
gestureRecognizer1 = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(gestureHandler:)];
gestureRecognizer1.delegate = self;
gestureRecognizer2 = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(gestureHandler:)];
gestureRecognizer2.delegate = self;
gestureRecognizer3 = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(gestureHandler:)];
gestureRecognizer3.delegate = self;
gestureRecognizer4 = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(gestureHandler:)];
gestureRecognizer4.delegate = self;
gestureRecognizer5 = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(gestureHandler:)];
gestureRecognizer5.delegate = self;
gestureRecognizer6 = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(gestureHandler:)];
gestureRecognizer6.delegate = self;
[imgView1 addGestureRecognizer:gestureRecognizer1];
[imgView2 addGestureRecognizer:gestureRecognizer2];
[imgView3 addGestureRecognizer:gestureRecognizer3];
[imgView4 addGestureRecognizer:gestureRecognizer4];
[imgView5 addGestureRecognizer:gestureRecognizer5];
[imgView6 addGestureRecognizer:gestureRecognizer6];
Yes, one view per gesture recognizer. So if you want only one recognizer, put it on the superview, e.g.:
UILongPressGestureRecognizer *gestureRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(gestureHandler:)];
[self.view addGestureRecognizer:gestureRecognizer];
And then, in your handler, you can:
- (void)handleLongPress:(UILongPressGestureRecognizer *)sender
{
CGPoint location = [sender locationInView:self.view];
if (sender.state == UIGestureRecognizerStateBegan)
{
for (UIView *view in self.view.subviews)
{
if ([view isKindOfClass:[UIImageView class]] && CGRectContainsPoint(view.frame, location))
{
UIImageView *image = (UIImageView *) view;
// ok, now you know which image you received your long press for
// do whatever you wanted on it at this point
return;
}
}
}
}
By the way, if you do that, you don't need to worry about enabling user interaction on the images, either.
Finally, you don't need to worry about specifying your gesture recognizer's delegate unless you're going to conform to UIGestureRecognizerDelegate, which this isn't. Also note that I'm using a local var for my recognizer because there's no reason to hang onto it.
Update:
While the above code works fine, perhaps even better would be a custom long press gesture recognizer that would fail if the long press didn't take place over an image (this way it's more likely to play well in case you have other gesture recognizers taking place in your view). So:
#import <UIKit/UIGestureRecognizerSubclass.h>
#interface ImageLongPressGestureRecognizer : UILongPressGestureRecognizer
#property (nonatomic, weak) UIImageView *imageview;
#end
#implementation ImageLongPressGestureRecognizer
#synthesize imageview = _imageview;
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
self.imageview = nil;
[super touchesBegan:touches withEvent:event];
CGPoint location = [self locationInView:self.view];
for (UIView *view in self.view.subviews)
{
if ([view isKindOfClass:[UIImageView class]] && CGRectContainsPoint(view.frame, location))
{
self.imageview = (UIImageView *)view;
return;
}
}
self.state = UIGestureRecognizerStateFailed;
}
#end
then create your gesture recognizer accordingly, using this new subclass:
ImageLongPressGestureRecognizer *gestureRecognizer = [[ImageLongPressGestureRecognizer alloc] initWithTarget:self action:#selector(handleLongPress:)];
[self.view addGestureRecognizer:gestureRecognizer];
and then, as a nice little benefit of this subclassing, your main gesture recognizer is simplified, namely:
- (void)handleLongPress:(ImageLongPressGestureRecognizer *)sender
{
if (sender.state == UIGestureRecognizerStateBegan)
{
// you can now do whatever you want with sender.imageview, e.g. this makes it blink for you:
[UIView animateWithDuration:0.5
animations:^{
sender.imageview.alpha = 0.0;
} completion:^(BOOL finished){
[UIView animateWithDuration:0.5
animations:^{
sender.imageview.alpha = 1.0;
}
completion:nil];
}];
}
}
You can't attach a gesture recognizer to more than one object (as you discovered). One solution to what you are doing might be to subclass UIImageView and have setup code in that class so each view creates its recognizer, etc.
I guess, first of all, you should make an array of views and array of recognizers (mutable array, if needed) and then populate it. It will help you to use cycles to avoid code duplication.
As for multiple view with one recognizer - no, it's not possible, answered here.
I have created a UIViewController, which contains a UIView object.
I want the UIView object response to a single tap by 1 finger, and also pinch by 2 fingers.
I have clicked the "User Interaction Enabled" and the "Multiple touch" options in the xib.
I create both UITapGestureRecognizer, and UIPinchGestureRecognizer inside the UIView function initWithFrame:, as it is the only entry point for the UIView object. But the object doesn't response to the UIGestureRecognizer objects. Why? Or, where is the best place to put the UIGestureRecognizer objects?
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
// single tap
UITapGestureRecognizer* singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
singleTap.numberOfTapsRequired = 1;
singleTap.numberOfTouchesRequired = 1;
[self addGestureRecognizer: singleTap];
// 2 fingers pinch
UIPinchGestureRecognizer* doubleMove = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:#selector(handleDoubleMove:)];
[self addGestureRecognizer: doubleMove];
}
return self;
}
Your problem is that when you instantiate your custom view subclass in IB, initWithCoder: is called. If you had done it programmatically using initWithFrame: it would have worked properly.
Two ways you can fix this,
Move the gestures setup to a different method and call them in both initWithFrame: and initWithCoder:. I would recommend doing this if you intend to reuse this component and expose some kind of callbacks on gestures.
If you want to implement this once and have a lot of interacting with the controller element, add them in viewDidLoad.
I tried your code and it works for me.
Where are you setting the view? Maybe it has any other view in front, or its superview has userInteractionEnabled disabled.
I created a UIView subclass and added this code:
-(void) handleSingleTap:(UITapGestureRecognizer *)gr {
NSLog(#"handleSingleTap");
}
-(void) handleDoubleMove:(UIPinchGestureRecognizer *)gr {
NSLog(#"handleDoubleMove");
}
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
// single tap
UITapGestureRecognizer* singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
singleTap.numberOfTapsRequired = 1;
singleTap.numberOfTouchesRequired = 1;
[self addGestureRecognizer: singleTap];
// 2 fingers pinch
UIPinchGestureRecognizer* doubleMove = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:#selector(handleDoubleMove:)];
[self addGestureRecognizer: doubleMove];
}
return self;
}
Then, in my controller:
-(void) viewDidLoad {
[super viewDidLoad];
MyView * myView = [[MyView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
myView.backgroundColor = [UIColor greenColor];
[self.view addSubview:myView];
[myView release];
}
And it works.
i think if you are working with .xib, initialization can also be done in
-(void)awakeFormNib;
Adding the GestureRecognizers is typically done in the viewDidLoad method of the UIViewController.