LibGUI: Add GAction class and make GMenu deal in actions rather than strings.

Author: https://github.com/awesomekling
Commit: https://github.com/SerenityOS/serenity/commit/3085e400bcd

Applications/Terminal/main.cpp

@@ -14,6 +14,7 @@
 #include <LibGUI/GWidget.h>
 #include <LibGUI/GWindow.h>
 #include <LibGUI/GMenuBar.h>
+#include <LibGUI/GAction.h>
 
 static void make_shell(int ptm_fd)
 {
@@ -95,38 +96,28 @@ int main(int argc, char** argv)
     auto menubar = make<GMenuBar>();
 
     auto app_menu = make<GMenu>("Terminal");
-    app_menu->add_item(0, "Quit");
-    app_menu->on_item_activation = [] (unsigned identifier) {
-        if (identifier == 0) {
-            dbgprintf("Terminal: Quit menu activated!\n");
-            GApplication::the().exit(0);
-            return;
-        }
-    };
+    app_menu->add_action(make<GAction>("Quit", String(), [] (const GAction&) {
+        dbgprintf("Terminal: Quit menu activated!\n");
+        GApplication::the().exit(0);
+        return;
+    }));
     menubar->add_menu(move(app_menu));
 
     auto font_menu = make<GMenu>("Font");
-    font_menu->add_item(0, "Liza Thin");
-    font_menu->add_item(1, "Liza Regular");
-    font_menu->add_item(2, "Liza Bold");
-    font_menu->on_item_activation = [&terminal] (unsigned identifier) {
-        switch (identifier) {
-        case 0:
-            terminal.set_font(Font::load_from_file("/res/fonts/LizaThin8x10.font"));
-            break;
-        case 1:
-            terminal.set_font(Font::load_from_file("/res/fonts/LizaRegular8x10.font"));
-            break;
-        case 2:
-            terminal.set_font(Font::load_from_file("/res/fonts/LizaBold8x10.font"));
-            break;
-        }
+    auto handle_font_selection = [&terminal] (const GAction& action) {
+        terminal.set_font(Font::load_from_file(action.custom_data()));
         terminal.force_repaint();
     };
+    font_menu->add_action(make<GAction>("Liza Thin", "/res/fonts/LizaThin8x10.font", move(handle_font_selection)));
+    font_menu->add_action(make<GAction>("Liza Regular", "/res/fonts/LizaRegular8x10.font", move(handle_font_selection)));
+    font_menu->add_action(make<GAction>("Liza Bold", "/res/fonts/LizaBold8x10.font", move(handle_font_selection)));
+
     menubar->add_menu(move(font_menu));
 
     auto help_menu = make<GMenu>("Help");
-    help_menu->add_item(0, "About");
+    help_menu->add_action(make<GAction>("About", [] (const GAction&) {
+        dbgprintf("FIXME: Implement Help/About\n");
+    }));
     menubar->add_menu(move(help_menu));
 
     app.set_menubar(move(menubar));

LibGUI/GAction.cpp

@@ -0,0 +1,23 @@
+#include <LibGUI/GAction.h>
+
+GAction::GAction(const String& text, const String& custom_data, Function<void(const GAction&)> on_activation_callback)
+    : m_text(text)
+    , on_activation(move(on_activation_callback))
+    , m_custom_data(custom_data)
+{
+}
+
+GAction::GAction(const String& text, Function<void(const GAction&)> on_activation_callback)
+    : GAction(text, String(), move(on_activation_callback))
+{
+}
+
+GAction::~GAction()
+{
+}
+
+void GAction::activate()
+{
+    if (on_activation)
+        on_activation(*this);
+}

LibGUI/GAction.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <AK/AKString.h>
+#include <AK/Function.h>
+
+class GAction {
+public:
+    GAction(const String& text, Function<void(const GAction&)> = nullptr);
+    GAction(const String& text, const String& custom_data = String(), Function<void(const GAction&)> = nullptr);
+    ~GAction();
+
+    String text() const { return m_text; }
+    String custom_data() const { return m_custom_data; }
+
+    Function<void(GAction&)> on_activation;
+
+    void activate();
+
+private:
+    String m_text;
+    String m_custom_data;
+};
+

LibGUI/GEventLoop.cpp

@@ -2,6 +2,7 @@
 #include "GEvent.h"
 #include "GObject.h"
 #include "GWindow.h"
+#include <LibGUI/GAction.h>
 #include <LibGUI/GNotifier.h>
 #include <LibGUI/GMenu.h>
 #include <LibC/unistd.h>
@@ -156,8 +157,8 @@ void GEventLoop::handle_menu_event(const GUI_Event& event)
             dbgprintf("GEventLoop received event for invalid window ID %d\n", event.window_id);
             return;
         }
-        if (menu->on_item_activation)
-            menu->on_item_activation(event.menu.identifier);
+        if (auto* action = menu->action_at(event.menu.identifier))
+            action->activate();
         return;
     }
     ASSERT_NOT_REACHED();

LibGUI/GMenu.cpp

@@ -1,3 +1,4 @@
+#include <LibGUI/GAction.h>
 #include <LibGUI/GMenu.h>
 #include <LibC/gui.h>
 #include <AK/HashMap.h>
@@ -32,26 +33,38 @@ GMenu::~GMenu()
     }
 }
 
-void GMenu::add_item(unsigned identifier, const String& text)
+void GMenu::add_action(OwnPtr<GAction>&& action)
 {
-    m_items.append({ identifier, text });
+    m_items.append(make<GMenuItem>(move(action)));
 }
 
 void GMenu::add_separator()
 {
-    m_items.append(GMenuItem(GMenuItem::Separator));
+    m_items.append(make<GMenuItem>(GMenuItem::Separator));
 }
 
 int GMenu::realize_menu()
 {
     m_menu_id = gui_menu_create(m_name.characters());
     ASSERT(m_menu_id > 0);
-    for (auto& item : m_items) {
-        if (item.type() == GMenuItem::Separator)
+    for (size_t i = 0; i < m_items.size(); ++i) {
+        auto& item = *m_items[i];
+        if (item.type() == GMenuItem::Separator) {
             gui_menu_add_separator(m_menu_id);
-        else if (item.type() == GMenuItem::Text)
-            gui_menu_add_item(m_menu_id, item.identifier(), item.text().characters());
+            continue;
+        }
+        if (item.type() == GMenuItem::Action) {
+            auto& action = *item.action();
+            gui_menu_add_item(m_menu_id, i, action.text().characters());
+        }
     }
     all_menus().set(m_menu_id, this);
     return m_menu_id;
 }
+
+GAction* GMenu::action_at(size_t index)
+{
+    if (index >= m_items.size())
+        return nullptr;
+    return m_items[index]->action();
+}

LibGUI/GMenu.h

@@ -4,6 +4,8 @@
 #include <AK/Function.h>
 #include <AK/Vector.h>
 
+class GAction;
+
 class GMenu {
 public:
     explicit GMenu(const String& name);
@@ -11,7 +13,9 @@ public:
 
     static GMenu* from_menu_id(int);
 
-    void add_item(unsigned identifier, const String& text);
+    GAction* action_at(size_t);
+
+    void add_action(OwnPtr<GAction>&&);
     void add_separator();
 
     Function<void(unsigned)> on_item_activation;
@@ -23,5 +27,5 @@ private:
 
     int m_menu_id { 0 };
     String m_name;
-    Vector<GMenuItem> m_items;
+    Vector<OwnPtr<GMenuItem>> m_items;
 };

LibGUI/GMenuItem.cpp

@@ -1,14 +1,14 @@
 #include <LibGUI/GMenuItem.h>
+#include <LibGUI/GAction.h>
 
 GMenuItem::GMenuItem(Type type)
     : m_type(type)
 {
 }
 
-GMenuItem::GMenuItem(unsigned identifier, const String& text)
-    : m_type(Text)
-    , m_identifier(identifier)
-    , m_text(text)
+GMenuItem::GMenuItem(OwnPtr<GAction>&& action)
+    : m_type(Action)
+    , m_action(move(action))
 {
 }
 

LibGUI/GMenuItem.h

@@ -2,21 +2,25 @@
 
 #include <AK/AKString.h>
 
+class GAction;
+
 class GMenuItem {
 public:
-    enum Type { Invalid, Text, Separator };
+    enum Type { Invalid, Action, Separator };
 
     explicit GMenuItem(Type);
-    GMenuItem(unsigned identifier, const String& text);
+    explicit GMenuItem(OwnPtr<GAction>&&);
     ~GMenuItem();
 
     Type type() const { return m_type; }
-    String text() const { return m_text; }
+    String text() const;
+    const GAction* action() const { return m_action.ptr(); }
+    GAction* action() { return m_action.ptr(); }
     unsigned identifier() const { return m_identifier; }
 
 private:
     Type m_type { Invalid };
     unsigned m_identifier { 0 };
-    String m_text;
+    OwnPtr<GAction> m_action;
 };
 

LibGUI/Makefile

@@ -25,6 +25,7 @@ LIBGUI_OBJS = \
     GMenu.o \
     GMenuItem.o \
     GApplication.o \
+    GAction.o \
     GWindow.o
 
 OBJS = $(SHAREDGRAPHICS_OBJS) $(LIBGUI_OBJS)