Native window decorations for Windows 10 (using JNI)

[DevCharly]

This PR is the successor of PR #262 and implements native window decorations for Windows 10 using JNI. This avoids the 3MB dependency on JNA. Also flatlaf-native-jna-1.1-SNAPSHOT.jar is no longer needed. A small 9kB DLL is now contained in flatlaf.jar. This DLL is extracted at startup to folder $TEMP/flatlaf.temp. Since it is not possible to delete it when the application exits (because Windows has locked it), unused temporary DLL is deleted on next startup.

This PR enables dark frame/dialog title bar and embedded menu bar with all JREs while still having:

• native Window 10 border drop shadows
• native Window 10 resize functionality
• Windows 10 snapping functionality
• native Windows 10 system window menu when right-clicking on title bar or left-clicking on application icon

Try it

To try it out, either build from source or download the build artifacts ZIP from GitHub Actions
(at the bottom of that page):
https://github.com/JFormDesigner/FlatLaf/actions/runs/642361750

The ZIP contains the demo flatlaf-demo-1.1-SNAPSHOT.jar (contains all dependencies).

To test in own applications, add flatlaf-1.1-SNAPSHOT.jar to the classpath.

Enable/disable

This feature is enabled by default on Windows 10.

If you don't like/want it, you can disable it with:

UIManager.put( "TitlePane.useWindowDecorations", false );

It is also possible to disable only the embedded menu bar (and keep the dark title pane) with:

UIManager.put( "TitlePane.menuBarEmbedded", false );

It is also possible to disable this on command line with following VM options:

-Dflatlaf.useWindowDecorations=false
-Dflatlaf.menuBarEmbedded=false

If you have following code in your app, you can remove it (no longer necessary):

// enable window decorations
JFrame.setDefaultLookAndFeelDecorated( true );
JDialog.setDefaultLookAndFeelDecorated( true );

JetBrains Runtime (JRE)

If you're using JetBrains Runtime 11 to run your app, this feature is not used.
Instead the native window decorations feature provided by the JetBrains Runtime is used (as in FlatLaf 1.0).

fixes issue #170

[DevCharly]

This feature is now enabled by default (see updated main post)

[basix86]

Very nice and complex job.
Congratulations!