How to unhide view with animations

问题:

Say I have a hidden view in Xcode for iOS. Now, when I set the view to not hidden (view.hidden=NO), how can I make it so that it now appears, but with animations?

回答1:

What you probably want is not to set view.hidden, but to set view.alpha to 0 (corresponds to hidden = YES) or 1 (hidden = NO).

You can then use implicit animations to show the view, e.g

[UIView animateWithDuration:0.3 animations:^() {
    view.alpha = 1.0;
}];

回答2:

If you want other animations than only fading then use this method

[UIView transitionWithView:_yourView duration:1.0 options:UIViewAnimationOptionTransitionCurlDown animations:^(void){

            [_yourView setHidden:NO];

        } completion:nil];

回答3:

For a fade, you can adjust the alpha property of the view.

myView.alpha = 0;
[UIView animateWithDuration:0.5 animations:^{
    myView.alpha = 1;
}];

That will apply a fade in over 0.5 seconds to the view myView. Many UIView properties are animatable; you aren't just limited to alpha fades. You can change background colours, or even rotate and scale a view, with animation. If you need further control and advanced animation, you can then move into Core Animation - a much more complex animation framework.

回答4:

-(void)showView{

  [UIView beginAnimations: @"Fade Out" context:nil];
  [UIView setAnimationDelay:0];
  [UIView setAnimationDuration:.5];
  //show your view with Fade animation lets say myView
  [myView setHidden:FALSE];
  [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(hideView) userInfo:nil repeats:YES];

  [UIView commitAnimations];
}


-(void)hideView{
  [UIView beginAnimations: @"Fade In" context:nil];
  [UIView setAnimationDelay:0];
  [UIView setAnimationDuration:.5];
  //hide your view with Fad animation
  [myView setHidden:TRUE];
  [UIView commitAnimations];
}

OR you can try this way

self.yourView.alpha = 0.0;
[UIView beginAnimations:@"Fade-in" context:NULL];
[UIView setAnimationDuration:1.0];
self.yourView.alpha = 1.0;
[UIView commitAnimations];