I'm implementing long press in UITableViewCell using following code. Everything works fine except that when long press is over I have to click two times on a cell to select it.
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(handleLongPress:)];
longPress.minimumPressDuration = 0.5;
longPress.delegate = self;
[cell addGestureRecognizer:longPress];
Does anybody knows the reason behind this behavior ?
Thanks.
Related
We need to set a UIButton with 2 methods, the first one is when you touch it (down and up) you get one action , but when you long press it, you get another one.
For example, to get data about it when you long click, and when regular click , another thing.
How can i achieve this with UIButton ?
UIButton *CAT = [UIButton buttonWithType:UIButtonTypeCustom];
CAT.contentHorizontalAlignment=UIControlContentHorizontalAlignmentCenter;
CAT.backgroundColor=[UIColor clearColor];
[CAT addTarget:self action:#selector(newcat:)forControlEvents:UIControlEventTouchUpInside];
I have started with adding it a gesture with this
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(longPress:)];
[CAT addGestureRecognizer:longPress];
But this triggered only when you take off your finger .
i want it to be triggered while my finger is still there after 1-2 seconds .
Can i do that? and can i adjust the time required for it to trigger ?
You can use the event UIControlEventTouchDown, use delay time for long press and you must deal with UIControlEventTouchUpInside and UIControlEventTouchUpOutside. good luck!
this is normal method
UIButton *CAT = [UIButton buttonWithType:UIButtonTypeCustom];
CAT.contentHorizontalAlignment=UIControlContentHorizontalAlignmentCenter;
CAT.backgroundColor=[UIColor clearColor];
[CAT addTarget:self action:#selector(newcat:)forControlEvents:UIControlEventTouchUpInside];
UILongPressGestureRecognizer *longpressGesture =
[[UILongPressGestureRecognizer alloc] initWithTarget:self
action:#selector(longPressHandler:)];
longpressGesture.minimumPressDuration = 5; // set the time interval
[longpressGesture setDelegate:self];
[CAT addGestureRecognizer:longpressGesture];
[self.view addsubview: CAT];
longpress action method
- (void)longPressHandler:(UILongPressGestureRecognizer *)gestureRecognizer {
NSLog(#"longPressHandler");
// do long press action
}
normal action method
-(void) newcat:(id)sender
{
// do normal action here
}
Today I tried to add an additional UILongPressGestureRecognizer to an UISwitch, which did not really work. My code is the following:
UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(doSomething:)];
[lpgr setDelaysTouchesBegan:YES];
[lpgr setDelaysTouchesEnded:YES];
[lpgr setCancelsTouchesInView:YES];
[self.switcher addGestureRecognizer:lpgr];
in the viewDidLoad method of the viewController that is the parent viewController of that switch. (the switcher is an instance variable, set through a storyboard. The IBOutlet is set properly from the UISwitch to the switcherProperty of its viewController).
On a couple of other controls (like a UIButton, UISlider, UIStepper and so on) this works, even without the touches cancelled or delayed, and perfectly triggers the target method. However, with my switch, it refuses that behavior.
I have tried removing any other gestureRecognizer on the UISwitch by iterating through all gestureRecognizers on that switch and calling [switcher removeGestureRecognizer: ... ], I´ve also set all of them to require my longPressGestureRecognizer to fail. Other types of gestureRecognizers don´t fire as well.
As far as I understand, GestureRecognizers will receive touches, before the view or control, which they belong to, receives them. Thus, setCancelsTouchesInView:YES and setDelaysTouchesInView:YES should enable the gestureRecognizer to handle every single gesture until it fails or succeeds, without the view knowing, right?
--------------EDIT------------------
The whole content of my method:
- (void)viewDidLoad
{
[super viewDidLoad];
UIGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(edit:)];
[self.view addGestureRecognizer:lpgr];
lpgr = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(edit:)];
[self.button addGestureRecognizer:lpgr];
lpgr = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(edit:)];
[self.slider addGestureRecognizer:lpgr];
lpgr = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(edit:)];
[self.segmentedControl addGestureRecognizer:lpgr];
lpgr = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(edit:)];
[self.switcher addGestureRecognizer:lpgr];
lpgr = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(edit:)];
[self.stepper addGestureRecognizer:lpgr];
}
As I said, for the other controls this is working, only the switch does not want to work
try with it
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
// Disallow recognition of tap gestures in the segmented control.
if ((touch.view == yourSwitch)) {//change it to your condition
return NO;
}
return YES;
}
make sure you confirm UIGestureRecognizerDelegate for it to work.
As the title of this question said, I need to create a view where it needs to have action when one tap it or hold it. That means I have to add UITapGestureRecognizer and a UILongPressGestureRecognizer. I have already tried it. Somehow it redirect me to the screen where I needed to go, but it has affected it's back button. Affected by in the sense of it goes back to default text which is "Item" and it cannot perform it's assigned action.
Yes you can add these two gestures in one view. See the below code
UITapGestureRecognizer *singleTapRecognizer = [[UITapGestureRecognizer alloc]initWithTarget:self action:#selector(didTap:)];
singleTapRecognizer.numberOfTapsRequired = 1;
singleTapRecognizer.delegate = self;
[self.view addGestureRecognizer:singleTapRecognizer];
UILongPressGestureRecognizer *longPressRecognizer = [[UILongPressGestureRecognizer alloc]initWithTarget:self action:#selector(didLongPress:)];
[longPressRecognizer setDelegate:self];
longPressRecognizer.allowableMovement = 1.0f;
longPressRecognizer.minimumPressDuration = 2.0;
[self.view addGestureRecognizer:longPressRecognizer];
As i mentioned in my comment you can do so,here is some piece of code to help you out.
UITapGestureRecognizer * recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
recognizer.delegate = self;
[view addGestureRecognizer:recognizer];
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc]
initWithTarget:self
action:#selector(handleLongPress:)];
longPress.minimumPressDuration = 2.0;
[view addGestureRecognizer:longPress];
and here are are some links too for your better understanding:-
https://developer.apple.com/library/ios/documentation/uikit/reference/UILongPressGestureRecognizer_Class/Reference/Reference.html
https://developer.apple.com/library/ios/documentation/uikit/reference/UITapGestureRecognizer_Class/Reference/Reference.html
Hope this will help you out.
Problem：Fast UITableViewCell with a UIWebView
Using UITapGestureRecognizer achieve UIWebView click event,but when click link in UIWebView, UITapGestureRecognizer and Link event will be triggered. How to solve it？
cellForRowAtIndexPath code:
UITapGestureRecognizer* singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
singleTap.numberOfTapsRequired = 1;
singleTap.numberOfTouchesRequired = 1;
singleTap.view.tag = indexPath.row;
singleTap.delegate = self;
singleTap.cancelsTouchesInView = NO;
[cell.wvContent addGestureRecognizer:singleTap]; // cell.wvContent is UIWebView
Click on any row will be repeated trigger multiple times，how to solve it？
Its not advised to use webview within tableview cell. Both classses are inherited from scrollview :)
I have this code in viewDidLoad:
UILongPressGestureRecognizer *change = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(dragGestureChange:)];
[imageView addGestureRecognizer:change];
for (UILongPressGestureRecognizer *gestureRecognizer in imageView.gestureRecognizers)
{
[gestureRecognizer requireGestureRecognizerToFail:change];
}
when I call the class where is this code, the first time it's all ok , but the second time it crash because EXC_BAD_ACCESS; it don't happens if instead of an imageView I use a scrollView, why???
With this code, you are requiring all recognizers (including change) to fail for change to succeed, which cannot be good
UILongPressGestureRecognizer *change = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(dragGestureChange:)];
[imageView addGestureRecognizer:change];
for (UILongPressGestureRecognizer *gestureRecognizer in imageView.gestureRecognizers)
{
[gestureRecognizer requireGestureRecognizerToFail:change];
}
you should change it to this
UILongPressGestureRecognizer *change = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(dragGestureChange:)];
for (UILongPressGestureRecognizer *gestureRecognizer in imageView.gestureRecognizers)
{
[gestureRecognizer requireGestureRecognizerToFail:change];
}
[imageView addGestureRecognizer:change];
And you should release change here. Don't know if that will actually solve your problem, can't see anything else wrong in what you posted.
Maybe try this: UIButtonLongTab. Use the Background-Image for your Images. I use this in an App within a ScrollView and it works without problem.