I just want to add that the native window handles are available prior to
the windows being shown if you listen to the observable list
Window.getWindows().
On 02/04/2025 16:01, Bahaa Zaid wrote:
Hello,
Modern macOS apps tend to expand the client area of the window to take
the entire window area including the titlebar. This is usually done by:
1. Setting NSWindow.titlebarAppearsTransparent to true.
2. Setting NSWindow.styleMask NSWindowStyleMaskFullSizeContentView flag.
This can be useful because it gives the app modern look, make use of
all available window real-estate, and allows JavaFX developers to
create completely custom windows like UNDECORATED styles without
loosing the platform resize-window feature and the three window buttons.
Swing supports this already using code like this:
final var frame = new JFrame();
final var rootPane = frame.getRootPane();
rootPane.putClientProperty("apple.awt.fullWindowContent", true);
rootPane.putClientProperty("apple.awt.transparentTitleBar", true);
This can be done easily today using reflection to access non-public
API to get the Stage native NSWindow handle and using FFM to change
styleMask and set the titlebarAppearsTransparent property. I have
created an example here
(https://github.com/bahaa/jfx-transparent-window-titlebar). But this
approach has the following drawbacks:
* It uses non-public API.
* JavaFX stage native window handle is available only after the
stage is shown, this cause some flicker because the window style
is changed after it’s shown to the user.
I think JavaFX should support this out of the box. One possible
solution is to introduce a new StageStyle that behaves like UNIFIED
style (it falls back to DECORATED) if it’s not supported by the
platform. I think something similar can be done on Windows
(https://learn.microsoft.com/en-us/windows/win32/dwm/customframe) but
I’m not sure about GTK.
Thanks,
Bahaa.
