On Wed, 10 Jan 2024 23:45:57 GMT, Sergey Bylokhov <s...@openjdk.org> wrote:
>> A black screen is seen on newer versions of macOS (13.3 & above) when a
>> window is set to full-screen using `setFullScreenWindow()`. The root cause
>> was narrowed down to the shield level of the full-screen window vs the
>> shield level of the captured display.
>>
>> Following solutions were explored -
>>
>> 1. Setting `kCGMaximumWindowLevelKey` as the shield level for the full
>> screen window. But setting the fullscreen window to maximum available window
>> level might cause z-order issues when other popup/screen savers are involved.
>>
>> int shieldLevel = CGWindowLevelForKey(kCGMaximumWindowLevelKey);
>> window.preFullScreenLevel = [nsWindow level];
>> [nsWindow setLevel: shieldLevel];
>>
>> 2. Raise the window's level slightly (shieldLevel + 1) above the system
>> shield window.
>>
>> int shieldLevel = CGShieldingWindowLevel();
>> window.preFullScreenLevel = [nsWindow level];
>> [nsWindow setLevel: (shieldLevel + 1)];
>>
>> 3. Keeping the shielding level as-is and bringing the window to the
>> foreground after display is captured. The 3rd approach **(also the one Apple
>> recommends)** ensures that the full screen window has focus as well as being
>> visible and also maintains the correct z-order. This solution works as
>> expected on older (< 13.3) and newer versions (13.3 & above) of macOS.
>>
>> if (CGDisplayCapture(aID) == kCGErrorSuccess) {
>> ...
>> ...
>> int shieldLevel = CGShieldingWindowLevel();
>> window.preFullScreenLevel = [nsWindow level];
>> [nsWindow setLevel: shieldLevel];
>> [nsWindow makeKeyAndOrderFront: nil];
>> }
>
> How it will work now(and worked before) if the user will call toBack() on the
> such fullscreen window?
@mrserb
> How it will work now(and worked before) if the user will call toBack() on the
> such fullscreen window?
Tested both cases
- current fix on macOS 13.3 & above + fullScreenWindow.toBack()
- original code on older macOS version (11.5) + fullScreenWindow.toBack()
It works the same in both cases - the shield window becomes the topmost window
and a black screen is seen.
-------------
PR Comment: https://git.openjdk.org/jdk/pull/17358#issuecomment-1886019314
