Black bars with HDMI Adapter on iPad 2

Question

My app supports HDMI Output.

I asked the code for the resolution of the TV and got 1920 x 1080 px for

externalScreen.bounds

OK, everything fine. I've setup my views and tried it on the TV ...

BUT: There were black bars on the bottom / top / sides of the screen though the TV was detected correctly as 1920 x 1080 and my view is also set up correctly?

Why is the format wrong?

P.S. When I mirror the home screen, it also shows the bars, when I watch a video with the Youtube App, the black bars disappear?

Thank you for your help!

Update:

OK, although I got this output in my console:

A new screen got connected: <UIScreen: 0x3439a0; bounds = {{0, 0}, {1920, 1080}}; mode = <UIScreenMode: 0x345240; size = 1920.000000 x 1080.000000>>

... I still get the black frame. I init my view with CGRectMake(0.0f,0.0f,1920.0f,1080.0f) for test purposes.

This is the view I can see on my screen (note the black bars):

Answer 1

The home screen will have black bars because the aspect ratio doesn't match 16:9 (it's 4:3 I think). As far as the external display, check the frame of your main view (the view that's supposed to span the screen). It is probably not set to 1920 x 1080

edit: I used this code for a project where I had to output from an iPad to a 1920 x 1080 display and it worked

- (void) screenDidConnect:(NSNotification *)aNotification
{
    NSLog(@"A new screen got connected: %@", [aNotification object]);
    //[self printScreenInfo];

    UIScreen* newScreen = [aNotification object];

    CGRect screenBounds = newScreen.bounds;

    if (!self.externalWindow)
    {
        self.externalWindow = [[UIWindow alloc] initWithFrame:screenBounds];

        self.externalWindow.screen = newScreen;
        self.externalViewController.view.frame = externalWindow.frame;

        [self.externalWindow addSubview:externalViewController.view];

        self.externalWindow.hidden = NO;
        // Set the initial UI for the window.
        // [externalViewController displaySelectionInSecondaryWindow:externalWindow];

    }
}

Answer 2

externalScreen.overscanCompensation = UIScreenOverscanCompensationInsetApplicationFrame;

Answer 3

The setting that works best for most TVs is:

externalScreen.overscanCompensation = UIScreenOverscanCompensationInsetBounds | UIScreenOverscanCompensationInsetApplicationFrame; // this is the same as setting it to 3

Just setting it to UIScreenOverscanCompensationInsetApplicationFrame can cause misalignment of the UIWindow contents.