LibGUI+WindowServer: Add support for per-GWidget context menus.

You can now simply assign a GMenu as a GWidget's context menu and it will
automagically pop up on right click. :^)

Applications/VisualBuilder/VBForm.cpp

@@ -1,6 +1,8 @@
 #include "VBForm.h"
 #include "VBWidget.h"
 #include <LibGUI/GPainter.h>
+#include <LibGUI/GMenu.h>
+#include <LibGUI/GAction.h>
 
 static VBForm* s_current;
 VBForm* VBForm::current()
@@ -32,6 +34,11 @@ VBForm::VBForm(const String& name, GWidget* parent)
     auto groupbox1 = VBWidget::create(VBWidgetType::GGroupBox, *this);
     groupbox1->set_rect({ 300, 150, 161, 51 });
     m_widgets.append(move(groupbox1));
+
+    auto context_menu = make<GMenu>("Context menu");
+    context_menu->add_action(GAction::create("Item 1", [] (auto&) { dbgprintf("Item 1 activated!\n"); }));
+    context_menu->add_action(GAction::create("Item 2", [] (auto&) { dbgprintf("Item 2 activated!\n"); }));
+    set_context_menu(move(context_menu));
 }
 
 void VBForm::insert_widget(VBWidgetType type)

LibGUI/GMenu.cpp

@@ -39,6 +39,17 @@ void GMenu::add_separator()
     m_items.append(make<GMenuItem>(m_menu_id, GMenuItem::Separator));
 }
 
+void GMenu::popup(const Point& screen_position)
+{
+    if (!m_menu_id)
+        realize_menu();
+    WSAPI_ClientMessage request;
+    request.type = WSAPI_ClientMessage::Type::PopupMenu;
+    request.menu.menu_id = m_menu_id;
+    request.menu.position = screen_position;
+    GEventLoop::post_message_to_server(request);
+}
+
 int GMenu::realize_menu()
 {
     WSAPI_ClientMessage request;

LibGUI/GMenu.h

@@ -5,6 +5,7 @@
 #include <AK/Vector.h>
 
 class GAction;
+class Point;
 
 class GMenu {
 public:
@@ -18,6 +19,8 @@ public:
     void add_action(Retained<GAction>&&);
     void add_separator();
 
+    void popup(const Point& screen_position);
+
     Function<void(unsigned)> on_item_activation;
 
 private:

LibGUI/GWidget.cpp

@@ -7,7 +7,7 @@
 #include <SharedGraphics/GraphicsBitmap.h>
 #include <LibGUI/GPainter.h>
 #include <LibGUI/GApplication.h>
-
+#include <LibGUI/GMenu.h>
 #include <unistd.h>
 
 GWidget::GWidget(GWidget* parent)
@@ -161,12 +161,14 @@ void GWidget::handle_mouseup_event(GMouseEvent& event)
         return;
     // It's a click.. but is it a doubleclick?
     // FIXME: This needs improvement.
-    int elapsed_since_last_click = m_click_clock.elapsed();
-    dbgprintf("Click clock elapsed: %d\n", m_click_clock.elapsed());
-    if (elapsed_since_last_click < 250) {
-        doubleclick_event(event);
-    } else {
-        m_click_clock.start();
+    if (m_click_clock.is_valid()) {
+        int elapsed_since_last_click = m_click_clock.elapsed();
+        dbgprintf("Click clock elapsed: %d\n", m_click_clock.elapsed());
+        if (elapsed_since_last_click < 250) {
+            doubleclick_event(event);
+        } else {
+            m_click_clock.start();
+        }
     }
 }
 
@@ -174,6 +176,13 @@ void GWidget::handle_mousedown_event(GMouseEvent& event)
 {
     if (accepts_focus())
         set_focus(true);
+    if (event.button() == GMouseButton::Right) {
+        if (m_context_menu) {
+            m_context_menu->popup(screen_relative_rect().location().translated(event.position()));
+            return;
+        }
+    }
+    // FIXME: Maybe the click clock should be per-button.
     if (!m_click_clock.is_valid())
         m_click_clock.start();
     mousedown_event(event);
@@ -416,3 +425,10 @@ void GWidget::set_enabled(bool enabled)
     m_enabled = enabled;
     update();
 }
+
+void GWidget::set_context_menu(OwnPtr<GMenu>&& context_menu)
+{
+    // FIXME: Support switching context menus.
+    ASSERT(!m_context_menu);
+    m_context_menu = move(context_menu);
+}

LibGUI/GWidget.h

@@ -11,6 +11,7 @@
 
 class GraphicsBitmap;
 class GLayout;
+class GMenu;
 class GWindow;
 
 enum class SizePolicy { Fixed, Fill };
@@ -41,6 +42,9 @@ public:
     bool is_enabled() const { return m_enabled; }
     void set_enabled(bool);
 
+    const GMenu* context_menu() const { return m_context_menu.ptr(); }
+    void set_context_menu(OwnPtr<GMenu>&&);
+
     virtual void event(CEvent&) override;
     virtual void paint_event(GPaintEvent&);
     virtual void resize_event(GResizeEvent&);
@@ -186,4 +190,5 @@ private:
     bool m_enabled { true };
 
     CElapsedTimer m_click_clock;
+    OwnPtr<GMenu> m_context_menu;
 };

Servers/WindowServer/WSAPITypes.h

@@ -192,6 +192,7 @@ struct WSAPI_ClientMessage {
         GetWallpaper,
         SetWindowOverrideCursor,
         WM_SetActiveWindow,
+        PopupMenu,
     };
     Type type { Invalid };
     int window_id { -1 };
@@ -214,6 +215,7 @@ struct WSAPI_ClientMessage {
             char shortcut_text[32];
             int shortcut_text_length;
             bool enabled;
+            WSAPI_Point position;
         } menu;
         struct {
             WSAPI_Rect rect;

Servers/WindowServer/WSClientConnection.cpp

@@ -223,6 +223,19 @@ void WSClientConnection::handle_request(const WSAPIAddMenuItemRequest& request)
     post_message(response);
 }
 
+void WSClientConnection::handle_request(const WSAPIPopupMenuRequest& request)
+{
+    int menu_id = request.menu_id();
+    auto position = request.position();
+    auto it = m_menus.find(menu_id);
+    if (it == m_menus.end()) {
+        post_error("WSAPIPopupMenuRequest: Bad menu ID");
+        return;
+    }
+    auto& menu = *(*it).value;
+    menu.popup(position);
+}
+
 void WSClientConnection::handle_request(const WSAPIUpdateMenuItemRequest& request)
 {
     int menu_id = request.menu_id();
@@ -616,6 +629,8 @@ void WSClientConnection::on_request(const WSAPIClientRequest& request)
         return handle_request(static_cast<const WSAPISetWindowOverrideCursorRequest&>(request));
     case WSMessage::WMAPISetActiveWindowRequest:
         return handle_request(static_cast<const WSWMAPISetActiveWindowRequest&>(request));
+    case WSMessage::APIPopupMenuRequest:
+        return handle_request(static_cast<const WSAPIPopupMenuRequest&>(request));
     default:
         break;
     }

Servers/WindowServer/WSClientConnection.h

@@ -70,6 +70,7 @@ private:
     void handle_request(const WSAPIGetWallpaperRequest&);
     void handle_request(const WSAPISetWindowOverrideCursorRequest&);
     void handle_request(const WSWMAPISetActiveWindowRequest&);
+    void handle_request(const WSAPIPopupMenuRequest&);
 
     void post_error(const String&);
 

Servers/WindowServer/WSMenu.cpp

@@ -178,4 +178,14 @@ WSMenuItem* WSMenu::item_at(const Point& position)
 void WSMenu::close()
 {
     WSWindowManager::the().close_menu(*this);
-};
+    if (menu_window())
+        menu_window()->set_visible(false);
+}
+
+void WSMenu::popup(const Point& position)
+{
+    ASSERT(!is_empty());
+    auto& window = ensure_menu_window();
+    window.move_to(position);
+    window.set_visible(true);
+}

Servers/WindowServer/WSMenu.h

@@ -73,6 +73,8 @@ public:
 
     void close();
 
+    void popup(const Point&);
+
 private:
     virtual void on_message(const WSMessage&) override;
 

Servers/WindowServer/WSMessage.h

@@ -57,6 +57,7 @@ public:
         APIGetWallpaperRequest,
         APISetWindowOverrideCursorRequest,
         WMAPISetActiveWindowRequest,
+        APIPopupMenuRequest,
         __End_API_Client_Requests,
     };
 
@@ -189,6 +190,24 @@ private:
     int m_menu_id { 0 };
 };
 
+class WSAPIPopupMenuRequest : public WSAPIClientRequest {
+public:
+    WSAPIPopupMenuRequest(int client_id, int menu_id, const Point& position)
+        : WSAPIClientRequest(WSMessage::APIPopupMenuRequest, client_id)
+        , m_menu_id(menu_id)
+        , m_position(position)
+    {
+    }
+
+    int menu_id() const { return m_menu_id; }
+    Point position() const { return m_position; }
+
+private:
+    int m_menu_id;
+    Point m_position;
+};
+
+
 class WSAPICreateMenuRequest : public WSAPIClientRequest {
 public:
     WSAPICreateMenuRequest(int client_id, const String& text)

Servers/WindowServer/WSMessageLoop.cpp

@@ -290,6 +290,9 @@ void WSMessageLoop::on_receive_from_client(int client_id, const WSAPI_ClientMess
         ASSERT(message.text_length < (ssize_t)sizeof(message.text));
         post_message(client, make<WSAPICreateMenuRequest>(client_id, String(message.text, message.text_length)));
         break;
+    case WSAPI_ClientMessage::Type::PopupMenu:
+        post_message(client, make<WSAPIPopupMenuRequest>(client_id, message.menu.menu_id, message.menu.position));
+        break;
     case WSAPI_ClientMessage::Type::DestroyMenu:
         post_message(client, make<WSAPIDestroyMenuRequest>(client_id, message.menu.menu_id));
         break;