Problem in dragging textField

my problem is that textField does not save the last position so when I dropped my textField he returned to the starting position

- (void)panPiece:(UIPanGestureRecognizer *)gestureRecognizer
{
    if ([gestureRecognizer state] == UIGestureRecognizerStateBegan || [gestureRecognizer     state] == UIGestureRecognizerStateChanged) {
        CGPoi开发者_如何转开发nt translation = [gestureRecognizer translationInView:self.view];

        //textfieldToAdd.center = CGPointMake([textfieldToAdd center].x + translation.x, [textfieldToAdd center].y + translation.y);
        textfieldToAdd.center = CGPointMake(translation.x, translation.y);  
    }
}

As far as I know, when you use PanGestureRecognizer, you should reset it's translation to 0 every time you use it. So I would recommend you to rewrite this part of code like this:

- (void)panPiece:(UIPanGestureRecognizer *)gestureRecognizer
{
    if ([gestureRecognizer state] == UIGestureRecognizerStateBegan || [gestureRecognizer     state] == UIGestureRecognizerStateChanged) 
    {
        CGPoint translation = [gestureRecognizer translationInView:self.view];
        CGPoint textFieldCenter = textfieldToAdd.center;

        textfieldToAddCenter.x += translation.x;
        textfieldToAddCenter.y += translation.y;
        textfieldToAdd.center = textfieldCenter;

        [gestureRecognizer setTranslation:CGPointZero inView:self.view];
    }
}

Another possible reason could be calling of layoutSubviews method of textField superview.

Hope this'll help!