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Answer 1

A:

Use the UITouch timestamp property in touchesBegan to launch a timer or stop it when touchesEnded got fired

Thomas Joulin 2010-10-13 13:58:30

Thanks for your answer but how can i detect which row is concerned by the touch ?

foOg 2010-10-13 14:05:55

I might be wrong, but nothing is provided to help you do that. You'll have to get the indexes of the current visible cells with [tableView indexPathsForVisibleRows] and then, using some calculations (your tableView offset from the top + X times the rows) you'll know that the coordinates of your finger is on which row.

Thomas Joulin 2010-10-13 14:17:39

I'm sure that there is an easier way to do that, anyway if you have another idea, i'll be here :)

foOg 2010-10-13 14:32:46

I'd be glad to know too if something easier is possible. But I don't think there is, mostly because the is not the way Apple wants us to handle interactions... It looks like an Android way of thinking this "quick access menu". If it were my app, I'll handle it like the Twitter app. A swipe to the left displays the options

Thomas Joulin 2010-10-13 14:37:10

Yes, i thought about that, so if i really can't do it with a long press event, i'll use the swipe method. But, maybe someone in stack-overflow did it ...

foOg 2010-10-13 14:47:36

Answer 2

+1 A:

First add the long press gesture recognizer to the table view:

UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc] 
  initWithTarget:self action:@selector(handleLongPress:)];
lpgr.minimumPressDuration = 2.0; //seconds
lpgr.delegate = self;
[self.myTableView addGestureRecognizer:lpgr];
[lpgr release];

Then in the gesture handler:

-(void)handleLongPress:(UILongPressGestureRecognizer *)gestureRecognizer
{
    CGPoint p = [gestureRecognizer locationInView:self.myTableView];

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

You have to be careful with this so that it doesn't interfere with the user's normal tapping of the cell and also note that handleLongPress may fire multiple times before user lifts their finger.

aBitObvious 2010-10-13 14:49:59

Awesome !!! Thanks a lot! But a last little question: Why is the method handleLongPress is call when the touch ended ???

foOg 2010-10-13 15:15:22

It's not called when touch ends but can fire multiple times if the user keeps their finger on the cell for more than 4 seconds (in this example) before lifting it.

aBitObvious 2010-10-13 15:19:03

Correction: it fires multiple times to indicate the different states of the gesture (began, changed, ended, etc). So in the handler method, check the state property of the gesture recognizer to avoid doing the action at each state of the gesture. Eg: `if (gestureRecognizer.state == UIGestureRecognizerStateBegan) ...`.

aBitObvious 2010-10-18 15:12:36

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Long press on UITableView

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