On Thu, 30 Oct 2025 13:43:58 GMT, Lukasz Kostyra <[email protected]> wrote:
>> modules/javafx.graphics/src/main/native-glass/win/GlassWindow.cpp line 1959: >> >>> 1957: } >>> 1958: >>> 1959: ::ShowWindow(hWnd, visible ? SW_SHOWNA : SW_HIDE); >> >> Is this change needed? I presume that the idea behind it is that if it is a >> focusable window, it will be activated anyway? > > Yes, this is part of the fix. The values in question are: > - `SW_SHOW` - shows a window and activates it, sending the `WM_ACTIVATE` > message > - `SW_SHOWNA` - shows a window but doesn't activate it - activation is > postponed to us later calling `::SetForegroundWindow()` > > By using `SW_SHOWNA` we can postpone the window activation and have > `::SetForegroundWindow()` trigger it. If `::SetForegroundWindow()` succeeds, > window gets activated and gains focus, and `WM_ACTIVATE` gets sent, which > will then be captured by JavaFX message loop so we can notify Java-side that > we gained focus. If `::SetForegroundWindow()` fails, we see that in this > function and we can notify Java-side the focus has been lost. > > This is unfortunately a bit hacky, but I couldn't find another way of > establishing whether we actually have focus or not, especially combining that > with what `::SetForegroundWindow()` returns. With `SW_SHOW` the `WM_ACTIVATE` > message would go through despite `::SetForegroundWindow()` failing and us > ultimately _not_ having focus. > > My first attempt also considered leaving this part as-is and simply notifying > Java-side if we lost focus or not based on `::SetForegroundWindow()` result, > but that wasn't consistent. Postponing the window activation seemed to me as > the best bet here. On my system the `SetForegroundWindow` call activates the window and makes it the focus window. We get `WM_ACTIVATE` and `WM_SETFOCUS` and tell the Java side to set the focused property to true. Then `SetForegroundWindow` returns false and we tell the Java side to clear the focused property. ------------- PR Review Comment: https://git.openjdk.org/jfx/pull/1849#discussion_r2486382236
