[linux] fix closing of custom context menu #3329 (#3330)

* [linux] fix closing of custom context menu

* Update changelog

---------

Co-authored-by: Lea Anthony <lea.anthony@gmail.com>

mkdocs-website/docs/en/changelog.md

@@ -52,6 +52,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Correctly compute `startURL` across multiple `GetStartURL` invocations when `FRONTEND_DEVSERVER_URL` is present. [#3299](https://github.com/wailsapp/wails/pull/3299)
 - Fix the JS type of the `Screen` struct to match its Go counterpart by [@fbbdev](https://github.com/fbbdev) in [#3295](https://github.com/wailsapp/wails/pull/3295)
 - Fix the `WML.Reload` method to ensure proper cleanup of registered event listeners by [@fbbdev](https://github.com/fbbdev) in [#3295](https://github.com/wailsapp/wails/pull/3295)
+- Fix custom context menu closing immediately on linux by [@abichinger](https://github.com/abichinger) in [#3330](https://github.com/wailsapp/wails/pull/3330)
 - Fix the output path and extension of model files produced by the binding generator by [@fbbdev](https://github.com/fbbdev) in [#3334](https://github.com/wailsapp/wails/pull/3334)
 - Fix the import paths of model files in JS code produced by the binding generator by [@fbbdev](https://github.com/fbbdev) in [#3334](https://github.com/wailsapp/wails/pull/3334)
 

v3/pkg/application/linux_cgo.go

@@ -64,6 +64,7 @@ extern gboolean handleFocusEvent(GtkWidget*, GdkEvent*, uintptr_t);
 extern void handleLoadChanged(WebKitWebView*, WebKitLoadEvent, uintptr_t);
 void handleClick(void*);
 extern gboolean onButtonEvent(GtkWidget *widget, GdkEventButton *event, uintptr_t user_data);
+extern gboolean onMenuButtonEvent(GtkWidget *widget, GdkEventButton *event, uintptr_t user_data);
 extern void onDragNDrop(
    void         *target,
    GdkDragContext* context,
@@ -361,6 +362,13 @@ func appDestroy(application pointer) {
 	C.g_application_quit((*C.GApplication)(application))
 }
 
+func (w *linuxWebviewWindow) contextMenuSignals(menu pointer) {
+	c := NewCalloc()
+	defer c.Free()
+	winID := unsafe.Pointer(uintptr(C.uint(w.parent.ID())))
+	C.signal_connect(unsafe.Pointer(menu), c.String("button-release-event"), C.onMenuButtonEvent, winID)
+}
+
 func (w *linuxWebviewWindow) contextMenuShow(menu pointer, data *ContextMenuData) {
 	geometry := C.GdkRectangle{
 		x: C.int(data.X),
@@ -376,6 +384,7 @@ func (w *linuxWebviewWindow) contextMenuShow(menu pointer, data *ContextMenuData
 		C.GDK_GRAVITY_NORTH_WEST,
 		(*C.GdkEvent)(&event),
 	)
+	w.ctxMenuOpened = true
 }
 
 func (a *linuxApp) getCurrentWindowID() uint {
@@ -1329,6 +1338,30 @@ func onButtonEvent(_ *C.GtkWidget, event *C.GdkEventButton, data C.uintptr_t) C.
 	return C.gboolean(0)
 }
 
+//export onMenuButtonEvent
+func onMenuButtonEvent(_ *C.GtkWidget, event *C.GdkEventButton, data C.uintptr_t) C.gboolean {
+	// Constants (defined here to be easier to use with purego)
+	GdkButtonRelease := C.GDK_BUTTON_RELEASE // 7
+
+	windowId := uint(C.uint(data))
+	window := globalApplication.getWindowForID(windowId)
+	if window == nil {
+		return C.gboolean(0)
+	}
+	lw, ok := (window.(*WebviewWindow).impl).(*linuxWebviewWindow)
+	if !ok {
+		return C.gboolean(0)
+	}
+
+	// prevent custom context menu from closing immediately
+	if event.button == 3 && int(event._type) == GdkButtonRelease && lw.ctxMenuOpened {
+		lw.ctxMenuOpened = false
+		return C.gboolean(1)
+	}
+
+	return C.gboolean(0)
+}
+
 //export onDragNDrop
 func onDragNDrop(target unsafe.Pointer, context *C.GdkDragContext, x C.gint, y C.gint, seldata unsafe.Pointer, info C.guint, time C.guint, data unsafe.Pointer) {
 	var length C.gint

v3/pkg/application/webview_window_linux.go

@@ -20,20 +20,21 @@ type dragInfo struct {
 }
 
 type linuxWebviewWindow struct {
-	id           uint
-	application  pointer
-	window       pointer
-	webview      pointer
-	parent       *WebviewWindow
-	menubar      pointer
-	vbox         pointer
-	menu         *Menu
-	accels       pointer
-	lastWidth    int
-	lastHeight   int
-	drag         dragInfo
-	lastX, lastY int
-	gtkmenu      pointer
+	id            uint
+	application   pointer
+	window        pointer
+	webview       pointer
+	parent        *WebviewWindow
+	menubar       pointer
+	vbox          pointer
+	menu          *Menu
+	accels        pointer
+	lastWidth     int
+	lastHeight    int
+	drag          dragInfo
+	lastX, lastY  int
+	gtkmenu       pointer
+	ctxMenuOpened bool
 }
 
 var (
@@ -61,6 +62,9 @@ func (w *linuxWebviewWindow) openContextMenu(menu *Menu, data *ContextMenuData)
 	}
 	if menu.impl == nil {
 		ctxMenu.update()
+
+		native := ctxMenu.menu.impl.(*linuxMenu).native
+		w.contextMenuSignals(native)
 	}
 
 	native := ctxMenu.menu.impl.(*linuxMenu).native