LibGUI: Add GAbstractView::activate_selected()

This is a nice little utility to activate all the selected items,
which is what you usually want to do.

Libraries/LibGUI/GAbstractColumnView.cpp

@@ -383,9 +383,7 @@ void GAbstractColumnView::keydown_event(GKeyEvent& event)
         return;
     auto& model = *this->model();
     if (event.key() == KeyCode::Key_Return) {
-        selection().for_each_index([this](auto& index) {
-            activate(index);
-        });
+        activate_selected();
         return;
     }
     if (event.key() == KeyCode::Key_Up) {
@@ -457,13 +455,10 @@ void GAbstractColumnView::doubleclick_event(GMouseEvent& event)
         if (event.y() < header_height())
             return;
         if (!selection().is_empty()) {
-            if (is_editable()) {
+            if (is_editable())
                 begin_editing(selection().first());
-            } else {
-                selection().for_each_index([this](auto& index) {
-                    activate(index);
-                });
-            }
+            else
+                activate_selected();
         }
     }
 }

Libraries/LibGUI/GAbstractView.cpp

@@ -113,6 +113,16 @@ void GAbstractView::activate(const GModelIndex& index)
         on_activation(index);
 }
 
+void GAbstractView::activate_selected()
+{
+    if (!on_activation)
+        return;
+
+    selection().for_each_index([this](auto& index) {
+        on_activation(index);
+    });
+}
+
 void GAbstractView::notify_selection_changed(Badge<GModelSelection>)
 {
     did_update_selection();

Libraries/LibGUI/GAbstractView.h

@@ -51,6 +51,7 @@ protected:
 
     virtual void did_scroll() override;
     void activate(const GModelIndex&);
+    void activate_selected();
     void update_edit_widget_position();
 
     bool m_editable { false };

Libraries/LibGUI/GItemView.cpp

@@ -258,9 +258,7 @@ void GItemView::doubleclick_event(GMouseEvent& event)
         return;
     if (event.button() == GMouseButton::Left) {
         mousedown_event(event);
-        selection().for_each_index([this](auto& index) {
-            activate(index);
-        });
+        activate_selected();
     }
 }
 
@@ -352,9 +350,7 @@ void GItemView::keydown_event(GKeyEvent& event)
 
     auto& model = *this->model();
     if (event.key() == KeyCode::Key_Return) {
-        selection().for_each_index([this](auto& index) {
-            activate(index);
-        });
+        activate_selected();
         return;
     }
     if (event.key() == KeyCode::Key_Home) {

Libraries/LibGUI/GListView.cpp

@@ -161,9 +161,7 @@ void GListView::keydown_event(GKeyEvent& event)
         return;
     auto& model = *this->model();
     if (event.key() == KeyCode::Key_Return) {
-        selection().for_each_index([this](auto& index) {
-            activate(index);
-        });
+        activate_selected();
         return;
     }
     if (event.key() == KeyCode::Key_Up) {
@@ -233,13 +231,10 @@ void GListView::doubleclick_event(GMouseEvent& event)
         return;
     if (event.button() == GMouseButton::Left) {
         if (!selection().is_empty()) {
-            if (is_editable()) {
+            if (is_editable())
                 begin_editing(selection().first());
-            } else {
-                selection().for_each_index([this](auto& index) {
-                    activate(index);
-                });
-            }
+            else
+                activate_selected();
         }
     }
 }