Unable to display UIToolbar or UITabbar in iOS7

Question

I installed a new application with a tab bar at the bottom. The following is the method of viewDidAppear:my root view controller:

- (void)viewDidAppear:(BOOL)animated
{
    self.tabBarController.tabBar.alpha = 0.0f;

    [UIView animateWithDuration:10.0f delay:0 options:UIViewAnimationOptionBeginFromCurrentState animations:^{
        self.view.backgroundColor = [UIColor redColor];
        self.tabBarController.tabBar.alpha = 1.0f;
    } completion:nil];
}

I observe that as soon as the presentation appears, it has alpha = 1.0f. I expect it to start with alpha = 0.0f, and then disappear to have alpha = 1.0f. On the other hand, the background fades to have backgroundColorred as expected.

The same thing happens when I try to fade away UIToolbar.

Answer 1

Set GroupOpacity UIToolbar NO. , iOS 7. viewDidLoad:

if([self.view.layer respondsToSelector:@selector(setAllowsGroupOpacity:)]) {
    self.view.layer.allowsGroupOpacity = NO;
}