I have a small UITableView that is hidden when the view is loaded. When i click on "SHOW" UIButton, the UITableView is made visible by myTableView.hidden=NO;
I want to hide UITableView when a user touches outside its frame. Thanks for any help!
Best Approach
Simple.Before show up the UITable View add one more grayed out/Transparent view then add tap gesture recogniser on it to hide it . That's it.
Show Overlay View first - alpha will be 0.5f and background color should be clear color.
show the table view.
NOTE: over lay view should have tap recogniser which will hide the overlay and table view
in View did load
UITapGestureRecognizer *tapRecog = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(overlayDidTap:)];
[myOverLayView addGestureRecognizer:tapRecog];
- (void)overlayDidTap:(UITapGestureRecognizer *)gesture
{
//hide both overlay and table view here
}
Bad Approach
We should not add tap recogniser on main view itself. Because it may have lots of
controls inside of it. so when user tap on it. it will perform its operation. So to avoid
it we can simulate the same behaviour by above approach
You can get touch position by this:
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(singleTapGestureCaptured:)];
[self.view addGestureRecognizer:singleTap];
- (void)singleTapGestureCaptured:(UITapGestureRecognizer *)gesture
{
CGPoint touchPoint=[gesture locationInView:self.View];
}
Then just check if the point is in tableview frame. If not then hide the tableview. Hope this help. :)
Subclass UITableView, override pointInside:withEvent:. It is templated for this reason.
Something like:
-(BOOL)pointInside:(CGPoint) point withEvent:(UIEvent*) event
{
BOOL pointIsInsideTableView = [super pointInside:point withEvent:event];
BOOL pointIsOutsideTableView = // Some test
return pointIsInsideTableView || pointIsOutsideTableView;
}
So you can catch the touch in table view implementation, where it belongs logically in this case.
I'm having a bit of a problem with a UITapGestureRecognizer. I create it this way:
self.userInteractionEnabled = YES;
UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
tapRecognizer.cancelsTouchesInView = NO;
tapRecognizer.delaysTouchesBegan = YES;
tapRecognizer.delegate = self;
tapRecognizer.numberOfTapsRequired = 1;
tapRecognizer.numberOfTouchesRequired = 1;
[self addGestureRecognizer:tapRecognizer];
In the header file I also include and implement the shouldReceiveTouch: method like so:
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
return YES;
}
I've looked through countless threads of people with similar problems and can't seem to find a solution. I've heard that if the view you're adding the gesture recognizer has subviews with userInteractionEnabled set to YES, that could possibly interfere with the tap recognition, so I also include this:
for(UIView *subview in self.subviews) {
subview.userInteractionEnabled = NO;
}
Anyone know why the gesture recognizer doesn't work?
Edit:
Here are some details:
I'm adding the UITapGestureRecognizer to a UIView subclass.
I add the gesture recognizer in the subclass' initWithFrame: method.
I've verified that the gesture recognizer is being added by stepping through the portion of the code where it's actually added.
The view controller that contains this view does not have any gesture recognizers attached to it, but does implement touchesBegan, touchesMoved, and touchesEnded. However, according to this question, that the view controller implements those shouldn't affect the gesture recognition of the view.
Edit 2:
I've verified that there are no other views blocking the view with the gesture recognizer from receiving touches. I've also verified that the view is actually being added to the containing view controller's view. It seems like the problem's elsewhere.
Your set up should work, so I would guess that one of two things is happening. You may have forgotten to actually add this view to the ViewController's view, or there maybe another view placed on top of this view which is stealing the touches?
Another possibility causing the problem is that the view on which the UITapGestureRecognizer is added is not big enough, so when you tap on the screen, the touch point is not located in the view's bounds.
Also make sure the UIView is not transparent. Set the background color to e.g. black. This solved the problem for me.
It may seem like duplicate, but I can't actually find any good answer to my concrete situation.
I have some button with background image (1pt-wide, streched), icon-like image inside along with the text label. It's height is 33pt, I need to make it's hittest area 44pt-high.
I saw two solutions, but neither of them works for me.
First solution is to enlarge frame and adjust image so it would have some padding. But that is not acceptable for me, because I have both background image and image inside the button.
Second solution is to subclass UIButton (which is absolutely acceptable) and override - (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event. I did that, when I put some breakpoints in this method and tried to tap in desired area nothing happened (breakpoints worked when tapped inside the button frame).
Are there any other solutions? What could be possibly wrong with the second solution?
If you create the view programmatically, you can instantiate a UIView that is 44px high, add a tap gesture recognizer to it, and add your UIButton as a subview inside this view:
CGRect bigFrame = CGRectMake(0,0,100,44);
UIView *big = [[UIView alloc] initWithFrame:bigFrame];
UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(doPress)];
[big addGestureRecognizer:tapRecognizer];
UIButton *yourButton = ...
[big addSubview:yourButton];
[self.view addSubview:big];
Then implement the selector as:
- (void)doPress {
[yourButton sendActionsForControlEvents:UIControlEventTouchUpInside];
}
In that way, the outer view taps will be interpreted as button presses for your button.
When I add a subview to a MKMapView or to any of it's descendent views, touches will pass right through and affect the map.
This question is ultimately used to explain a bug that was fixed for my custom callout which adds a view to an annotation view. The callout is not to be dismissed when the callout is touched and this question is in reference to that. But for the case brevity I'll use a smaller example that demonstrates the problem.
Setting exclusiveTouch and userInteractionEnabled doesn't do anything. BTW.
Let's take a UIView and attach it to the mapView
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)]
view.backgroundColor = [UIColor blackColor];
[mapView addSubview:view];
And let's add a gesture to the map as well
[mapView addGestureRecognizer:[[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(handleLongPress:)]];
And just have handleLongPress print something NSLog(#"longpress"); Now run the program and observe how long pressing the black uiview will cause the longPress to be triggered. If we add an annotation that shows a callout and select it, touching the black uiview will dismiss it. And if we scroll the map so that the annotation is under the black uiview, we'll be able to select the annotation. Now here's my solution. We tag the view that we're going to add to mapview with SOME_TAG and overwrite the hitTest method for MKMapView
#interface MKMapView(HackySolution)
#end
#implementation MKMapView(HackySolution)
- (UIView *) hitTest:(CGPoint)point withEvent:(UIEvent *)event {
UIView *view = [super hitTest:point withEvent:event];
// block touch propagation
if(view.tag == SOME_TAG){
view = nil;
}
return view;
}
#end
Now here's the deal, I may have solved my problem, but I really don't know why touches from the UIView are being passed right through onto the map. It doesn't make sense for a touch to a subview to be passed onto it's parentView. Maybe I'm not understanding how touches work. I mean if I place a button on a normal UIView and place another uiview on top of it, completely obscuring it, the button wouldn't get the touch right? I'm starting to second guess myself. :/
I can only guess that MKMapView is wired to do this, but I'm unsure. I thought there was a scroll view somewhere within MKMapView, but I ran through all the subviews and all the descendents and didn't find anything.
Is there a better way to solve this problem or is this the best it gets?
Any insight into the situation would be greatly appreciated.
I have placed an image (UIImageView) on the navigation bar. Now I want to detect the touch event and want to handle the event. How can I do that?
In practical terms, don't do that.
Instead add a button with Custom style (no button graphics unless you specify images) over the UIImageView. Then attach whatever methods you want called to that.
You can use that technique for many cases where you really want some area of the screen to act as a button instead of messing with the Touch stuff.
A UIImageView is derived from a UIView which is derived from UIResponder so it's ready to handle touch events. You'll want to provide the touchesBegan, touchesMoved, and touchesEnded methods and they'll get called if the user taps the image. If all you want is a tap event, it's easier to just use a custom button with the image set as the button image. But if you want finer-grain control over taps, moves, etc. this is the way to go.
You'll also want to look at a few more things:
Override canBecomeFirstResponder and return YES to indicate that the view can become the focus of touch events (the default is NO).
Set the userInteractionEnabled property to YES. The default for UIViews is YES, but for UIImageViews is NO so you have to explicitly turn it on.
If you want to respond to multi-touch events (i.e. pinch, zoom, etc) you'll want to set multipleTouchEnabled to YES.
To add a touch event to a UIImageView, use the following in your .m file:
UITapGestureRecognizer *newTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(myTapMethod)];
[myImageView setUserInteractionEnabled:YES];
[myImageView addGestureRecognizer:newTap];
-(void)myTapMethod{
// Treat image tap
}
You can also add a UIGestureRecognizer. It does not require you to add an additional element in your view hierarchy, but still provides you will all the nicely written code for handling touch events with a fairly simple interface:
UISwipeGestureRecognizer *swipeRight = [[UISwipeGestureRecognizer alloc]
initWithTarget:self action:#selector(handleSwipe:)];
swipeRight.direction = UISwipeGestureRecognizerDirectionRight;
[imgView_ addGestureRecognizer:swipeRight];
[swipeRight release];
UISwipeGestureRecognizer *swipeLeft = [[UISwipeGestureRecognizer alloc]
initWithTarget:self action:#selector(handleSwipe:)];
swipeLeft.direction = UISwipeGestureRecognizerDirectionLeft;
[imgView_ addGestureRecognizer:swipeLeft];
[swipeLeft release];
I've been on different threads on the past few hours trying to find a solution for my problem, to no avail. I see that many developers share this problem, and I think people here know about this. I have multiple images inside a UIScrollView, trying to get tap events on them.
I am not getting any events from an UIImangeView, but I do get an event from a similar UILable with very similar parameters I am setting to it. Under iOS 5.1.
I have already done the following:
set setUserInteractionEnabled to YES for both `UIImageView and parent
view .
set setMultipleTouchEnabled to YES for UIImageView.
Tried subclassing UIImageView, didn't help any.
Attaching some code below, in this code I initialize both a UIImageView and UILabel, the label works fine in terms of firing events. I tried keeping out irrelevant code.
UIImageView *single_view = [[UIImageView alloc]initWithFrame:CGRectMake(200, 200, 100, 100)];
single_view.image = img;
single_view.layer.zPosition = 4;
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(singleTapGestureCaptured:)];
[single_view addGestureRecognizer:singleTap];
[single_view setMultipleTouchEnabled:YES];
[single_view setUserInteractionEnabled:YES];
[self.myScrollView addSubview:single_view];
self.myScrollView.userInteractionEnabled = YES;
UILabel *testLabel = [[UILabel alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
testLabel.backgroundColor = [UIColor redColor];
[self.myScrollView addSubview:testLabel];
[testLabel addGestureRecognizer:singleTap];
[testLabel setMultipleTouchEnabled:YES];
[testLabel setUserInteractionEnabled:YES];
testLabel.layer.zPosition = 4;
And the method which handles the event:
- (void)singleTapGestureCaptured:(UITapGestureRecognizer *)gesture
{
UIView *tappedView = [gesture.view hitTest:[gesture locationInView:gesture.view] withEvent:nil];
NSLog(#"Touch event on view: %#", [tappedView class]);
}
As said, the label tap is received.
Instead of making a touchable UIImageView then placing it on the navbar, you should just create a UIBarButtonItem, which you make out of a UIImageView.
First make the image view:
UIImageView *yourImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"nameOfYourImage.png"]];
Then make the barbutton item out of your image view:
UIBarButtonItem *yourBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:yourImageView];
Then add the bar button item to your navigation bar:
self.navigationItem.rightBarButtonItem = yourBarButtonItem;
Remember that this code goes into the view controller which is inside a navigation controller viewcontroller array. So basically, this "touchable image-looking bar button item" will only appear in the navigation bar when this view controller when it's being shown. When you push another view controller, this navigation bar button item will disappear.
You might want to override the touchesBegan:withEvent: method of the UIView (or subclass) that contains your UIImageView subview.
Within this method, test if any of the UITouch touches fall inside the bounds of the UIImageView instance (let's say it is called imageView).
That is, does the CGPoint element [touch locationInView] intersect with with the CGRect element [imageView bounds]? Look into the function CGRectContainsPoint to run this test.
First, you should place an UIButton and then either you can add a background image for this button, or you need to place an UIImageView over the button.
Or:
You can add the tap gesture to a UIImageView so that get the click action when tap on the UIImageView.
For those of you looking for a Swift 4 solution to this answer, you can use the following to detect a touch event on a UIImageView.
let gestureRecognizer: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(imageViewTapped))
imageView.addGestureRecognizer(gestureRecognizer)
imageView.isUserInteractionEnabled = true
You will then need to define your selector as follows:
#objc func imageViewTapped() {
// Image has been tapped
}
Add gesture on that view. Add an image into that view, and then it would be detecting a gesture on the image too. You could try with the delegate method of the touch event. Then in that case it also might be detecting.