Animate UIButton becoming hidden and unhidden - objective-c

Question

So, I have a UIButton that, when a UITextField is in editing mode, becomes hidden and unhidden. The problem is, it changes perfectly fine (from hidden to unhidden), but doesn't animate. I've tried setAlpha: instead, but that only works when it is setting its alpha from 0 to 100, not 100 to 0. Here is my code so far:
-(BOOL) textFieldShouldBeginEditing:(UITextField *)textField
{
negButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
negButton.frame = CGRectMake(textField.frame.origin.x, textField.frame.origin.y, 37, textField.frame.size.height);
[negButton setHidden:YES];
return YES;
}
-(void) textFieldDidBeginEditing:(UITextField *)textField
{
if ([textField isEditing])
{
[UIView animateWithDuration:0.3 animations:^
{
CGRect frame = textField.frame;
frame.size.width -= 40;
frame.origin.x += 40;
[negButton setHidden:NO];
[textField setFrame:frame];
[self.view addSubview:negButton];
}];
}
}
-(void) textFieldDidEndEditing:(UITextField *)textField
{
[UIView animateWithDuration:0.3 animations:^
{
CGRect frame = textField.frame;
frame.size.width += 40;
frame.origin.x -= 40;
[negButton setHidden:YES];
[negButton removeFromSuperview];
[textField setFrame:frame];
}
];
}
EDIT: I resolved the issue. I just didn't have to call the removeFromSuperview function, and I had to switch from hidden to alpha. (See #David's answer below)

Answer 1

You have a problem with your animations. Change it to the following:
-(BOOL) textFieldShouldBeginEditing:(UITextField *)textField
{
negButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
negButton.frame = CGRectMake(textField.frame.origin.x, textField.frame.origin.y, 37, textField.frame.size.height);
[negButton setAlpha:0];
[self.view addSubView:negButton];
return YES;
}
-(void) textFieldDidBeginEditing:(UITextField *)textField
{
if ([textField isEditing])
{
CGRect frame = textField.frame;
frame.size.width -= 40;
frame.origin.x += 40;
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.3];
[negButton setAlpha:1];
[textField setFrame:frame];
[UIView commitAnimations];
}
}
-(void) textFieldDidEndEditing:(UITextField *)textField
{
CGRect frame = textField.frame;
frame.size.width += 40;
frame.origin.x -= 40;
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.3];
[negButton setAlpha:0];
[textField setFrame:frame];
[UIView commitAnimations];
[self performSelector:#selector(removeBtn) withObject:negButton afterDelay:0.3];
}
- (void)removeBtn:(UIButton*)button
{
[button removeFromSuperView];
}
You were removing the button from the view immediately instead of removing it after it had faded out.
Cheers!