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Locating long press gesture recognizer

I currently have Long Pres Gesture Recognizers on four different table views (two in each storyboard scene, so two storyboard scenes). I am creating these LPGRs with the following code in my ViewDidLoad method ...

//Add Long Press Gesture Reconizer
UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc] 
                                      initWithTarget:self action:@selector(handleLongPress:)];
lpgr.minimumPressDuration = 1; //seconds
lpgr.delegate = self;
[self.GolferOne addGestureRecognizer:lpgr];
[self.GolferTwo addGestureRecognizer:lpgr];
[self.GolferThree addGestureRecognizer:lpgr];
[self.GolferFour addGestureRecognizer:lpgr];
//Done Adding Long Press Gesture Reconizer

Next, I have another method that I want to use in NSLog where LPG was clicked ...

CGPoint p = [gestureRecognizer locationInView:self.GolferOne];

   NSIndexPath *indexPath = [self.GolferOne indexPathForRowAtPoint:p];
    if (indexPath == nil)
        NSLog(@"long press on table view but not on a row [Golfer One]");
    else
        NSLog(@"long press on table view at row %d [Golfer One]", indexPath.row);

    //Golfer Two

    p = [gestureRecognizer locationInView:self.GolferTwo];

    indexPath = [self.GolferTwo indexPathForRowAtPoint:p];
    if (indexPath == nil)
        NSLog(@"long press on table view but not on a row [Golfer Two]");
    else
        NSLog(@"long press on table view at row %d [Golfer Two]", indexPath.row);

    //Golfer Three

    p = [gestureRecognizer locationInView:self.GolferThree];

    indexPath = [self.GolferThree indexPathForRowAtPoint:p];
    if (indexPath == nil)
        NSLog(@"long press on table view but not on a row [Golfer Three]");
    else
        NSLog(@"long press on table view at row %d [Golfer Three]", indexPath.row);

    //Golfer Four

    p = [gestureRecognizer locationInView:self.GolferFour];

    indexPath = [self.GolferFour indexPathForRowAtPoint:p];
    if (indexPath == nil)
        NSLog(@"long press on table view but not on a row [Golfer Four]");
    else
        NSLog(@"long press on table view at row %d [Golfer Four]", indexPath.row);

I know why this won't work, but I can't seem to find a solution to get it to work. Instead of just saving one NSLog, it returns something four times (once for each golfer, because three of them have indexPath = nil)

Any help would be appreciated. Also, why is there such a lag behind it in NSLog?

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4 answers


You can get the touch point of the recognizer using

 -(void)handleLongPress:(UILongPressGestureRecognizer *)gestureRecognizer
{
 NSLog(@"%@",NSStringFromCGPoint([[gestureRecognizer valueForKey:@"_startPointScreen"] CGPointValue]));

}

you will get a point of view on the coordinate system for which your recognizer is added.



Your recognizer is only registered for the last golfer. you have to do this,

UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc] 
                                      initWithTarget:self action:@selector(handleLongPress:)];
lpgr.minimumPressDuration = 1; //seconds
[self.GolferOne addGestureRecognizer:lpgr];
[lgpr release];
lpgr = [[UILongPressGestureRecognizer alloc] 
                                      initWithTarget:self action:@selector(handleLongPress:)];
lpgr.minimumPressDuration = 1; //seconds

[self.GolferTwo addGestureRecognizer:lpgr];
[lgpr release];
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To locate gestures in a view from the location of the recognizers InView: property:



// Get the location of the gesture
CGPoint location = [recognizer locationInView:self.view];
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The long hit recognizer is applied to the entire view . To lag behind NSLog, you can simply use NSTimer. The way you can get the result as yours wants is with alpha zero buttons. When they let go (that's 1 second or 120), it records the touch.

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  • As TheDeveloper said, the long press gesture is for the whole view.

  • As an aside, if you are configuring gestures for multiple views, I believe you need a separate gesturer for each view. Not relevant here, but I see a lot of guys wondering why the gesture they were trying to assign to multiple views only works for one.

  • With long press gestures, I suggest you check your sender.state == UIGestureRecognizerStateEnded or Started or whatever you are looking for. You will receive multiple events triggered for the same user interaction.

  • If you have a gesture in the view and you want to see, for example, if the user has released their finger for a certain subset, you can get the CGPoint for the release (via locationInView as Vignesh pointed out), you can also get the CGRect for a specific frame of the view. and then check if CGPoint is inside CGRect via CGRectContainsPoint ().

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