iOS9: Custom UIWindow makes status bar disappear
When I create a custom UIWindow in iOS9, the window becomes visible on the screen, but the status bar suddenly disappears.
When the window becomes hidden, the status bar appears again.
Below, 2 screenshots of what I get on iOS9 with Xcode7 beta5.
Status bar while the custom window is hidden: 
Status bar while the custom window is visible: (The whole screen moves to the top.)
This is the code I'm using (which worked well on iOS8):
#define DEBUG_SHOWENV_HEIGHT 20.0f
@interface AppDelegate ()
@property (nonatomic) UIWindow* envWindow;
@end
-(UIWindow*)envWindow
{
if (_envWindow == nil)
{
// Create the window
_envWindow = [[UIWindow alloc] initWithFrame:CGRectMake(0.0f, self.window.frame.size.height, self.window.frame.size.width, DEBUG_SHOWENV_HEIGHT)];
_envWindow.rootViewController = [[UIViewController alloc] init]; // added since iOS9 to avoid the assertion
_envWindow.userInteractionEnabled = NO;
_envWindow.windowLevel = UIWindowLevelStatusBar;
_envWindow.backgroundColor = [UIColor colorWithRed:0.243 green:0.471 blue:0.992 alpha:0.8];
// Make a label
UILabel* labelEnv = [[UILabel alloc] initWithFrame:CGRectMake(8.0f, 0.0f, _envWindow.bounds.size.width - 16.0f, DEBUG_SHOWENV_HEIGHT)];
labelEnv.font = [UIFont boldSystemFontOfSize:12.0f];
labelEnv.textColor = [UIColor whiteColor];
labelEnv.text = @"DEVELOP ENVIRONMENT";
[_envWindow addSubview:labelEnv];
}
return _envWindow;
}
// ==== in applicationDidBecomeActive
// Show the window 2 seconds then hide it.
[self.envWindow.layer removeAllAnimations];
self.envWindow.frame = CGRectMake(0.0f, self.window.frame.size.height, self.window.frame.size.width, DEBUG_SHOWENV_HEIGHT);
self.envWindow.hidden = NO;
[UIView animateWithDuration:0.25f
delay:0.0f
options:UIViewAnimationOptionCurveEaseOut
animations:^{
self.envWindow.frame = CGRectMake(0.0f, self.window.frame.size.height - DEBUG_SHOWENV_HEIGHT, self.window.frame.size.width, DEBUG_SHOWENV_HEIGHT);
}
completion:^(BOOL finished) {
if (finished)
{
[UIView animateWithDuration:0.25f
delay:2.0f
options:UIViewAnimationOptionCurveEaseOut
animations:^{
self.envWindow.frame = CGRectMake(0.0f, self.window.frame.size.height, self.window.frame.size.width, DEBUG_SHOWENV_HEIGHT);
}
completion:^(BOOL finished) {
if (finished)
{
self.envWindow.hidden = YES;
}
}];
}
}];
I'd appreciate any help.
Solved. I needed to implement this method in the root view controller:
- (BOOL)prefersStatusBarHidden
{
return NO;
}
For some reasons, the root view controller in this UIWindow hid the status bar. (though it should return NO by default, normally)
So instead of doing:
_envWindow.rootViewController = [[UIViewController alloc] init]; // added since iOS9 to avoid the assertion
I created my own view controller with prefersStatusBarHidden overridden.
The line _envWindow.windowLevel = UIWindowLevelStatusBar; puts your window at the same level (z-ordering) as the status bar. I think that what you want is UIWindowLevelNormal , so that the status bar appears over it.
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