Linux: use X11 window manager events to move window and to show window menu (right-click on window title bar), if custom window decorations are enabled (issue #482)

2025-12-06 14:00:55 +03:00 · 2022-08-20 21:09:49 +02:00
parent 16f3f9e6ff
commit fb4576fc1b
18 changed files with 769 additions and 59 deletions
--- a/flatlaf-natives/README.md
+++ b/flatlaf-natives/README.md
@@ -2,4 +2,5 @@ FlatLaf Native Libraries
 ========================

 - [Windows 10 Native Library](flatlaf-natives-windows)
+- [Linux Native Library](flatlaf-natives-linux)
 - [Natives using JNA](flatlaf-natives-jna) (for development only)
--- a/flatlaf-natives/flatlaf-natives-jna/build.gradle.kts
+++ b/flatlaf-natives/flatlaf-natives-jna/build.gradle.kts
@@ -20,6 +20,6 @@ plugins {

 dependencies {
 	implementation( project( ":flatlaf-core" ) )
-	implementation( "net.java.dev.jna:jna:5.10.0" )
-	implementation( "net.java.dev.jna:jna-platform:5.10.0" )
+	implementation( "net.java.dev.jna:jna:5.12.1" )
+	implementation( "net.java.dev.jna:jna-platform:5.12.1" )
 }
--- a/flatlaf-natives/flatlaf-natives-jna/src/main/java/com/formdev/flatlaf/natives/jna/linux/X11WmUtils.java
+++ b/flatlaf-natives/flatlaf-natives-jna/src/main/java/com/formdev/flatlaf/natives/jna/linux/X11WmUtils.java
@@ -0,0 +1,135 @@
+/*
+ * Copyright 2022 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.natives.jna.linux;
+
+import java.awt.Window;
+import com.sun.jna.Native;
+import com.sun.jna.NativeLong;
+import com.sun.jna.Pointer;
+import com.sun.jna.platform.unix.X11;
+
+/**
+ * @author Karl Tauber
+ * @since 2.5
+ */
+public class X11WmUtils
+{
+	/**
+	 * Send _NET_WM_MOVERESIZE to window to initiate moving or resizing.
+	 *
+	 * Warning: Although the implementation of this method is (nearly) identical
+	 *          to the C++ implementation, this one does not work correctly.
+	 *          DO NOT USE.
+	 *
+	 * https://specifications.freedesktop.org/wm-spec/wm-spec-latest.html#idm45446104441728
+	 * https://gitlab.gnome.org/GNOME/gtk/-/blob/main/gdk/x11/gdksurface-x11.c#L3841-3881
+	 */
+	public static boolean xMoveOrResizeWindow( Window window, int x, int y, int direction ) {
+		System.out.println( "---- move or resize window: " + x + "," + y );
+		return sendEvent( window,
+			"_NET_WM_MOVERESIZE",
+			x,
+			y,
+			direction,
+			X11.Button1,		// left mouse button
+			1 );				// source indication
+	}
+
+	/**
+	 * Send _GTK_SHOW_WINDOW_MENU to window to show system window menu.
+	 *
+	 * Warning: Although the implementation of this method is (nearly) identical
+	 *          to the C++ implementation, this one does not work correctly.
+	 *          DO NOT USE.
+	 *
+	 * https://docs.gtk.org/gdk3/method.Window.show_window_menu.html
+	 * https://gitlab.gnome.org/GNOME/gtk/-/blob/main/gdk/x11/gdksurface-x11.c#L4751-4801
+	 */
+	public static boolean xShowWindowMenu( Window window, int x, int y ) {
+		System.out.println( "---- show window menu: " + x + "," + y );
+		return sendEvent( window,
+			"_GTK_SHOW_WINDOW_MENU",
+			0,				// device id TODO
+			x,
+			y,
+			0,
+			0 );
+	}
+
+	private static boolean sendEvent( Window window, String atom_name,
+		long data0, long data1, long data2, long data3, long data4 )
+	{
+		sun.awt.SunToolkit.awtLock();
+		try {
+
+			// open display and get root window
+			X11.Display display = X11.INSTANCE.XOpenDisplay( null );
+			X11.Window root = X11.INSTANCE.XDefaultRootWindow( display );
+
+			// get X11 window ID for AWT window
+			Pointer p = Native.getComponentPointer( window );
+			long windowsId = Pointer.nativeValue( p );
+			System.out.println( "WindowId = " + windowsId );
+
+			// ungrab pointer and keyboard to allow the window manager to grab them
+			System.out.println( "Ungrab Pointer =  " + X11Ext.INSTANCE.XUngrabPointer( display, new NativeLong( 0 ) ) );
+			System.out.println( "Ungrab Keyboard = " + X11.INSTANCE.XUngrabKeyboard( display, new NativeLong( 0 ) ) );
+
+			// build event structure
+			X11.Window w = new X11.Window( windowsId );
+			X11.XEvent event = new X11.XEvent();
+			event.type = X11.ClientMessage;
+			event.setType( X11.XClientMessageEvent.class );
+			event.xclient.type = X11.ClientMessage;
+			event.xclient.serial = new NativeLong( 0 );
+			event.xclient.send_event = 1;
+			event.xclient.message_type = X11.INSTANCE.XInternAtom( display, atom_name, false );
+			event.xclient.display = display;
+			event.xclient.window = w;
+			event.xclient.format = 32;
+			event.xclient.data.setType( NativeLong[].class );
+			event.xclient.data.l[0] = new NativeLong( data0 );
+			event.xclient.data.l[1] = new NativeLong( data1 );
+			event.xclient.data.l[2] = new NativeLong( data2 );
+			event.xclient.data.l[3] = new NativeLong( data3 );
+			event.xclient.data.l[4] = new NativeLong( data4 );
+
+			// send event
+			System.out.println( "SendEvent = " + X11.INSTANCE.XSendEvent( display, root, 0,
+				new NativeLong( X11.SubstructureNotifyMask | X11.SubstructureRedirectMask ), event ) );
+
+			System.out.println( "Flush = " + X11.INSTANCE.XFlush( display ) );
+			System.out.println( "CloseDisplay = " + X11.INSTANCE.XCloseDisplay( display ) );
+			System.out.println( "Done" );
+
+		} finally {
+			sun.awt.SunToolkit.awtUnlock();
+		}
+
+		return true;
+	}
+
+	//----- interface X11Ext --------------------------------------------------
+
+	interface X11Ext
+		extends X11
+	{
+		X11Ext INSTANCE = Native.load( "X11", X11Ext.class );
+
+		int XUngrabPointer( Display display, NativeLong time );
+	}
+}
--- a/flatlaf-natives/flatlaf-natives-linux/README.md
+++ b/flatlaf-natives/flatlaf-natives-linux/README.md
@@ -0,0 +1,39 @@
+FlatLaf Linux Native Library
+============================
+
+This sub-project contains the source code for the FlatLaf Linux native library.
+
+The native library can be built only on Linux and requires a C++ compiler.
+
+To be able to build FlatLaf on any platform, and without C++ compiler, the
+pre-built native library is checked into Git at
+[flatlaf-core/src/main/resources/com/formdev/flatlaf/natives/](https://github.com/JFormDesigner/FlatLaf/tree/main/flatlaf-core/src/main/resources/com/formdev/flatlaf/natives).
+
+The native library was built on a GitHub server with the help of GitHub Actions.
+See:
+[Native Libraries](https://github.com/JFormDesigner/FlatLaf/actions/workflows/natives.yml)
+workflow. Then the produced Artifacts ZIP was downloaded and the native library
+checked into Git.
+
+
+## Development
+
+To build the library on Linux, some packages needs to be installed.
+
+
+### Ubuntu
+
+`build-essential` contains GCC and development tools. `libxt-dev` contains the
+X11 toolkit development headers.
+
+~~~
+sudo apt update
+sudo apt install build-essential libxt-dev
+~~~
+
+
+### CentOS
+
+~~~
+sudo yum install libXt-devel
+~~~
--- a/flatlaf-natives/flatlaf-natives-linux/build.gradle.kts
+++ b/flatlaf-natives/flatlaf-natives-linux/build.gradle.kts
@@ -0,0 +1,89 @@
+/*
+ * Copyright 2022 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+plugins {
+	`cpp-library`
+	`flatlaf-cpp-library`
+	`flatlaf-jni-headers`
+}
+
+flatlafJniHeaders {
+	headers = listOf( "com_formdev_flatlaf_ui_FlatNativeLinuxLibrary.h" )
+}
+
+library {
+	targetMachines.set( listOf( machines.linux.x86_64 ) )
+}
+
+var javaHome = System.getProperty( "java.home" )
+if( javaHome.endsWith( "jre" ) )
+	javaHome += "/.."
+
+tasks {
+	register( "build-natives" ) {
+		group = "build"
+		description = "Builds natives"
+
+		if( org.gradle.internal.os.OperatingSystem.current().isLinux )
+			dependsOn( "linkRelease" )
+	}
+
+	withType<CppCompile>().configureEach {
+		onlyIf { name.contains( "Release" ) }
+
+		// generate and copy needed JNI headers
+		dependsOn( "jni-headers" )
+
+		includes.from(
+			"${javaHome}/include",
+			"${javaHome}/include/linux"
+		)
+
+		compilerArgs.addAll( toolChain.map {
+			when( it ) {
+				is Gcc, is Clang -> listOf()
+				else -> emptyList()
+			}
+		} )
+	}
+
+	withType<LinkSharedLibrary>().configureEach {
+		onlyIf { name.contains( "Release" ) }
+
+		val nativesDir = project( ":flatlaf-core" ).projectDir.resolve( "src/main/resources/com/formdev/flatlaf/natives" )
+		val libraryName = "libflatlaf-linux-x86_64.so"
+		val jawt = "jawt"
+		var jawtPath = "${javaHome}/lib"
+		if( JavaVersion.current() == JavaVersion.VERSION_1_8 )
+			jawtPath += "/amd64"
+
+		linkerArgs.addAll( toolChain.map {
+			when( it ) {
+				is Gcc, is Clang -> listOf( "-L${jawtPath}", "-l${jawt}" )
+				else -> emptyList()
+			}
+		} )
+
+		doLast {
+			// copy shared library to flatlaf-core resources
+			copy {
+				from( linkedFile )
+				into( nativesDir )
+				rename( "libflatlaf-natives-linux.so", libraryName )
+			}
+		}
+	}
+}
--- a/flatlaf-natives/flatlaf-natives-linux/src/main/cpp/X11WmUtils.cpp
+++ b/flatlaf-natives/flatlaf-natives-linux/src/main/cpp/X11WmUtils.cpp
@@ -0,0 +1,189 @@
+/*
+ * Copyright 2022 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <jawt.h>
+#include <linux/jawt_md.h>
+#include <X11/Xatom.h>
+#include "com_formdev_flatlaf_ui_FlatNativeLinuxLibrary.h"
+
+/**
+ * @author Karl Tauber
+ * @since 2.5
+ */
+
+
+bool sendEvent( JNIEnv *env, jobject window, const char *atom_name,
+	long data0, long data1, long data2, long data3, long data4 );
+bool isWMHintSupported( Display* display, Window rootWindow, Atom atom );
+Window getWindowHandle( JNIEnv* env, JAWT* awt, jobject window, Display** display_return );
+
+
+//---- JNI methods ------------------------------------------------------------
+
+/**
+ * Send _NET_WM_MOVERESIZE to window to initiate moving or resizing.
+ *
+ * https://specifications.freedesktop.org/wm-spec/wm-spec-latest.html#idm45446104441728
+ * https://gitlab.gnome.org/GNOME/gtk/-/blob/main/gdk/x11/gdksurface-x11.c#L3841-3881
+ */
+extern "C"
+JNIEXPORT jboolean JNICALL Java_com_formdev_flatlaf_ui_FlatNativeLinuxLibrary_xMoveOrResizeWindow
+	( JNIEnv *env, jclass cls, jobject window, jint x, jint y, jint direction )
+{
+	return sendEvent( env, window,
+		"_NET_WM_MOVERESIZE",
+		x,
+		y,
+		direction,
+		Button1,		// left mouse button
+		1 );			// source indication
+}
+
+/**
+ * Send _GTK_SHOW_WINDOW_MENU to window to show system window menu.
+ *
+ * https://docs.gtk.org/gdk3/method.Window.show_window_menu.html
+ * https://gitlab.gnome.org/GNOME/gtk/-/blob/main/gdk/x11/gdksurface-x11.c#L4751-4801
+ */
+extern "C"
+JNIEXPORT jboolean JNICALL Java_com_formdev_flatlaf_ui_FlatNativeLinuxLibrary_xShowWindowMenu
+	( JNIEnv *env, jclass cls, jobject window, jint x, jint y )
+{
+	// TODO pass useful value for (input?) devide id ?
+	//
+	// not used in Mutter and Metacity window manager (but maybe in other WMs?): 
+	//     https://github.com/GNOME/mutter/blob/5e5480e620ed5b307902d913f89f5937cc01a28f/src/x11/window-x11.c#L3437
+	//     https://github.com/GNOME/metacity/blob/7c1cc3ca1d8131499b9cf2ef50b295602ffd6112/src/core/window.c#L5699
+	// not used in KWin:
+	//     https://github.com/KDE/kwin/blob/7e1617c2808b7c9b23a8c786327fc88212e10b32/src/netinfo.cpp#L222
+
+	return sendEvent( env, window,
+		"_GTK_SHOW_WINDOW_MENU",
+		0,				//TODO device id
+		x,
+		y,
+		0,
+		0 );
+}
+
+bool sendEvent( JNIEnv *env, jobject window, const char *atom_name,
+	long data0, long data1, long data2, long data3, long data4 )
+{
+	// get the AWT
+	JAWT awt;
+	awt.version = JAWT_VERSION_1_4;
+	if( !JAWT_GetAWT( env, &awt ) )
+		return false;
+
+	// get Xlib window and display from AWT window
+	Display* display;
+	Window w = getWindowHandle( env, &awt, window, &display );
+	if( w == 0 )
+		return false;
+
+	awt.Lock( env );
+
+	Window rootWindow = XDefaultRootWindow( display );
+
+	// check whether window manager supports message
+	Atom atom = XInternAtom( display, atom_name, false );
+	if( !isWMHintSupported( display, rootWindow, atom ) ) {
+		awt.Unlock( env );
+		return false;
+	}
+
+	// ungrab (mouse) pointer and keyboard to allow the window manager to grab them
+	XUngrabPointer( display, CurrentTime );
+	XUngrabKeyboard( display, CurrentTime );
+
+	// build event structure
+	XClientMessageEvent xclient = { 0 };
+	xclient.type = ClientMessage;
+	xclient.window = w;
+	xclient.message_type = atom;
+	xclient.format = 32;
+	xclient.data.l[0] = data0;
+	xclient.data.l[1] = data1;
+	xclient.data.l[2] = data2;
+	xclient.data.l[3] = data3;
+	xclient.data.l[4] = data4;
+
+	// send event
+	XSendEvent( display, rootWindow, False,
+		SubstructureRedirectMask | SubstructureNotifyMask,
+		(XEvent*) &xclient );
+
+	awt.Unlock( env );
+	return true;
+}
+
+
+bool isWMHintSupported( Display* display, Window rootWindow, Atom atom ) {
+	Atom type;
+	int format;
+	unsigned long n_atoms;
+	unsigned long bytes_after;
+	Atom* atoms;
+
+	// get all supported hints
+	XGetWindowProperty( display, rootWindow,
+		XInternAtom( display, "_NET_SUPPORTED", false ),
+		0, 0xffff, False, XA_ATOM,
+		&type, &format, &n_atoms, &bytes_after, (unsigned char**) &atoms );
+
+	if( atoms == NULL )
+		return false;
+
+	if( type != XA_ATOM ) {
+		XFree( atoms );
+		return false;
+	}
+
+	bool supported = false;
+	for( int i = 0; i < n_atoms; i++ ) {
+		if( atoms[i] == atom ) {
+			supported = true;
+			break;
+		}
+	}
+
+	XFree( atoms );
+	return supported;
+}
+
+Window getWindowHandle( JNIEnv* env, JAWT* awt, jobject window, Display** display_return ) {
+	jawt_DrawingSurface* ds = awt->GetDrawingSurface( env, window );
+	if( ds == NULL )
+		return 0;
+
+	jint lock = ds->Lock( ds );
+	if( (lock & JAWT_LOCK_ERROR) != 0 ) {
+		awt->FreeDrawingSurface( ds );
+		return 0;
+	}
+
+	JAWT_DrawingSurfaceInfo* dsi = ds->GetDrawingSurfaceInfo( ds );
+	JAWT_X11DrawingSurfaceInfo* xdsi = (JAWT_X11DrawingSurfaceInfo*) dsi->platformInfo;
+
+	Window handle = xdsi->drawable;
+	*display_return = xdsi->display;
+
+	ds->FreeDrawingSurfaceInfo( dsi );
+	ds->Unlock( ds );
+	awt->FreeDrawingSurface( ds );
+
+	return handle;
+}
--- a/flatlaf-natives/flatlaf-natives-linux/src/main/headers/com_formdev_flatlaf_ui_FlatNativeLinuxLibrary.h
+++ b/flatlaf-natives/flatlaf-natives-linux/src/main/headers/com_formdev_flatlaf_ui_FlatNativeLinuxLibrary.h
@@ -0,0 +1,31 @@
+/* DO NOT EDIT THIS FILE - it is machine generated */
+#include <jni.h>
+/* Header for class com_formdev_flatlaf_ui_FlatNativeLinuxLibrary */
+
+#ifndef _Included_com_formdev_flatlaf_ui_FlatNativeLinuxLibrary
+#define _Included_com_formdev_flatlaf_ui_FlatNativeLinuxLibrary
+#ifdef __cplusplus
+extern "C" {
+#endif
+#undef com_formdev_flatlaf_ui_FlatNativeLinuxLibrary_MOVE
+#define com_formdev_flatlaf_ui_FlatNativeLinuxLibrary_MOVE 8L
+/*
+ * Class:     com_formdev_flatlaf_ui_FlatNativeLinuxLibrary
+ * Method:    xMoveOrResizeWindow
+ * Signature: (Ljava/awt/Window;III)Z
+ */
+JNIEXPORT jboolean JNICALL Java_com_formdev_flatlaf_ui_FlatNativeLinuxLibrary_xMoveOrResizeWindow
+  (JNIEnv *, jclass, jobject, jint, jint, jint);
+
+/*
+ * Class:     com_formdev_flatlaf_ui_FlatNativeLinuxLibrary
+ * Method:    xShowWindowMenu
+ * Signature: (Ljava/awt/Window;II)Z
+ */
+JNIEXPORT jboolean JNICALL Java_com_formdev_flatlaf_ui_FlatNativeLinuxLibrary_xShowWindowMenu
+  (JNIEnv *, jclass, jobject, jint, jint);
+
+#ifdef __cplusplus
+}
+#endif
+#endif
--- a/flatlaf-natives/flatlaf-natives-windows/build.gradle.kts
+++ b/flatlaf-natives/flatlaf-natives-windows/build.gradle.kts
@@ -16,22 +16,19 @@

 plugins {
 	`cpp-library`
+	`flatlaf-cpp-library`
+	`flatlaf-jni-headers`
+}
+
+flatlafJniHeaders {
+	headers = listOf(
+		"com_formdev_flatlaf_ui_FlatWindowsNativeWindowBorder.h",
+		"com_formdev_flatlaf_ui_FlatWindowsNativeWindowBorder_WndProc.h"
+	)
 }

 library {
 	targetMachines.set( listOf( machines.windows.x86, machines.windows.x86_64 ) )
-
-	// disable debuggable for release builds to make shared libraries smaller
-	binaries.configureEach( CppSharedLibrary::class ) {
-		with( compileTask.get() ) {
-			if( name.contains( "Release" ) )
-				isDebuggable = false
-		}
-		with( linkTask.get() ) {
-			if( name.contains( "Release" ) )
-				debuggable.set( false )
-		}
-	}
 }

 var javaHome = System.getProperty( "java.home" )
@@ -43,36 +40,15 @@ tasks {
 		group = "build"
 		description = "Builds natives"

-		dependsOn( "linkReleaseX86", "linkReleaseX86-64" )
+		if( org.gradle.internal.os.OperatingSystem.current().isWindows() )
+			dependsOn( "linkReleaseX86", "linkReleaseX86-64" )
 	}

 	withType<CppCompile>().configureEach {
 		onlyIf { name.contains( "Release" ) }

-		// depend on :flatlaf-core:compileJava because it generates the JNI headers
-		dependsOn( ":flatlaf-core:compileJava" )
-
-		doFirst {
-			println( "Used Tool Chain:" )
-			println( "  - ${toolChain.get()}" )
-			println( "Available Tool Chains:" )
-			toolChains.forEach {
-				println( "  - $it" )
-			}
-
-			// copy needed JNI headers
-			copy {
-				from( project( ":flatlaf-core" ).buildDir.resolve( "generated/jni-headers" ) )
-				into( "src/main/headers" )
-				include(
-					"com_formdev_flatlaf_ui_FlatWindowsNativeWindowBorder.h",
-					"com_formdev_flatlaf_ui_FlatWindowsNativeWindowBorder_WndProc.h"
-				)
-				filter<org.apache.tools.ant.filters.FixCrLfFilter>(
-					"eol" to org.apache.tools.ant.filters.FixCrLfFilter.CrLf.newInstance( "lf" )
-				)
-			}
-		}
+		// generate and copy needed JNI headers
+		dependsOn( "jni-headers" )

 		includes.from(
 			"${javaHome}/include",