I have this code:

- (void)my_button_tapped
{
if (my_button.tag == 0)
{
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:0.5];
    my_label.frame = CGRectMake(450, 455, 200, 20);
    [UIView commitAnimations];

    [my_button setBackgroundImage:[UIImage imageNamed:@"check.png"] forState:UIControlStateNormal];
    my_button.tag = 1;
}
else
{
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:0.5];
    my_label.frame = CGRectMake(450, 455, 0, 20);
    [UIView commitAnimations];

    [my_button setBackgroundImage:nil forState:UIControlStateNormal];
    my_button.tag = 0;
}
}

When I tap my_button first time the label is expanded into 200px width, when I press the button again the label decreases to 0px width but immediately at button press the text disappears. What's wrong?