LibGUI: Remove parent parameter to GUI::Widget constructor

Libraries/LibGUI/AbstractButton.cpp

@@ -31,14 +31,8 @@
 
 namespace GUI {
 
-AbstractButton::AbstractButton(Widget* parent)
-    : AbstractButton({}, parent)
-{
-}
-
-AbstractButton::AbstractButton(const StringView& text, Widget* parent)
-    : Widget(parent)
-    , m_text(text)
+AbstractButton::AbstractButton(const StringView& text)
+    : m_text(text)
 {
     m_auto_repeat_timer = add<Core::Timer>();
     m_auto_repeat_timer->on_timeout = [this] {

Libraries/LibGUI/AbstractButton.h

@@ -60,8 +60,7 @@ public:
     void set_auto_repeat_interval(int interval) { m_auto_repeat_interval = interval; }
 
 protected:
-    explicit AbstractButton(Widget* parent = nullptr);
-    AbstractButton(const StringView&, Widget* parent = nullptr);
+    explicit AbstractButton(const StringView& = {});
 
     virtual void mousedown_event(MouseEvent&) override;
     virtual void mousemove_event(MouseEvent&) override;

Libraries/LibGUI/AbstractTableView.cpp

@@ -39,8 +39,7 @@ namespace GUI {
 
 static const int minimum_column_width = 2;
 
-AbstractTableView::AbstractTableView(Widget* parent)
-    : AbstractView(parent)
+AbstractTableView::AbstractTableView()
 {
     set_should_hide_unnecessary_scrollbars(true);
 }

Libraries/LibGUI/AbstractTableView.h

@@ -72,7 +72,7 @@ public:
 
 protected:
     virtual ~AbstractTableView() override;
-    explicit AbstractTableView(Widget* parent = nullptr);
+    AbstractTableView();
 
     virtual void did_update_model() override;
     virtual void mouseup_event(MouseEvent&) override;

Libraries/LibGUI/AbstractView.cpp

@@ -37,9 +37,8 @@
 
 namespace GUI {
 
-AbstractView::AbstractView(Widget* parent)
-    : ScrollableWidget(parent)
-    , m_selection(*this)
+AbstractView::AbstractView()
+    : m_selection(*this)
 {
 }
 

Libraries/LibGUI/AbstractView.h

@@ -73,7 +73,7 @@ public:
     NonnullRefPtr<Gfx::Font> font_for_index(const ModelIndex&) const;
 
 protected:
-    explicit AbstractView(Widget* parent = nullptr);
+    AbstractView();
     virtual ~AbstractView() override;
 
     virtual void mousedown_event(MouseEvent&) override;

Libraries/LibGUI/Button.cpp

@@ -36,13 +36,8 @@
 
 namespace GUI {
 
-Button::Button(Widget* parent)
-    : AbstractButton(parent)
-{
-}
-
-Button::Button(const StringView& text, Widget* parent)
-    : AbstractButton(text, parent)
+Button::Button(const StringView& text)
+    : AbstractButton(text)
 {
 }
 

Libraries/LibGUI/Button.h

@@ -62,8 +62,7 @@ public:
     void set_focusable(bool b) { m_focusable = b; }
 
 protected:
-    Button(const StringView& text, Widget* parent = nullptr);
-    explicit Button(Widget* parent = nullptr);
+    explicit Button(const StringView& text = {});
     virtual void paint_event(PaintEvent&) override;
 
 private:

Libraries/LibGUI/CheckBox.cpp

@@ -52,13 +52,8 @@ static const int s_checked_bitmap_height = 9;
 static const int s_box_width = 13;
 static const int s_box_height = 13;
 
-CheckBox::CheckBox(Widget* parent)
-    : AbstractButton(parent)
-{
-}
-
-CheckBox::CheckBox(const StringView& text, Widget* parent)
-    : AbstractButton(text, parent)
+CheckBox::CheckBox(const StringView& text)
+    : AbstractButton(text)
 {
 }
 

Libraries/LibGUI/CheckBox.h

@@ -38,8 +38,7 @@ public:
     virtual void click() override;
 
 private:
-    CheckBox(const StringView&, Widget* parent = nullptr);
-    explicit CheckBox(Widget* parent = nullptr);
+    explicit CheckBox(const StringView& = {});
 
     // These don't make sense for a check box, so hide them.
     using AbstractButton::auto_repeat_interval;

Libraries/LibGUI/ColumnsView.cpp

@@ -47,8 +47,7 @@ static const char* s_arrow_bitmap_data = {
 static const int s_arrow_bitmap_width = 9;
 static const int s_arrow_bitmap_height = 9;
 
-ColumnsView::ColumnsView(Widget* parent)
-    : AbstractView(parent)
+ColumnsView::ColumnsView()
 {
     set_fill_with_background_color(true);
     set_background_role(ColorRole::Base);

Libraries/LibGUI/ColumnsView.h

@@ -40,8 +40,8 @@ public:
     virtual ModelIndex index_at_event_position(const Gfx::Point&) const override;
 
 private:
-    ColumnsView(Widget* parent = nullptr);
-    virtual ~ColumnsView();
+    ColumnsView();
+    virtual ~ColumnsView() override;
     void push_column(ModelIndex& parent_index);
     void update_column_sizes();
 

Libraries/LibGUI/ComboBox.cpp

@@ -35,8 +35,7 @@
 
 namespace GUI {
 
-ComboBox::ComboBox(Widget* parent)
-    : Widget(parent)
+ComboBox::ComboBox()
 {
     m_editor = add<TextBox>();
     m_editor->on_change = [this] {
@@ -57,11 +56,11 @@ ComboBox::ComboBox(Widget* parent)
             open();
     };
 
-    m_list_window = Window::construct(this);
+    m_list_window = add<Window>();
     // FIXME: This is obviously not a tooltip window, but it's the closest thing to what we want atm.
     m_list_window->set_window_type(WindowType::Tooltip);
 
-    m_list_view = ListView::construct(nullptr);
+    m_list_view = ListView::construct();
     m_list_view->horizontal_scrollbar().set_visible(false);
     m_list_window->set_main_widget(m_list_view);
 

Libraries/LibGUI/ComboBox.h

@@ -56,7 +56,7 @@ public:
     Function<void()> on_return_pressed;
 
 protected:
-    explicit ComboBox(Widget* parent = nullptr);
+    ComboBox();
     virtual void resize_event(ResizeEvent&) override;
 
 private:

Libraries/LibGUI/Frame.cpp

@@ -31,8 +31,7 @@
 
 namespace GUI {
 
-Frame::Frame(Widget* parent)
-    : Widget(parent)
+Frame::Frame()
 {
     set_frame_thickness(2);
     set_frame_shape(Gfx::FrameShape::Container);

Libraries/LibGUI/Frame.h

@@ -49,7 +49,7 @@ public:
     Gfx::Rect frame_inner_rect() const { return frame_inner_rect_for_size(size()); }
 
 protected:
-    explicit Frame(Widget* parent = nullptr);
+    Frame();
     void paint_event(PaintEvent&) override;
 
 private:

Libraries/LibGUI/GroupBox.cpp

@@ -32,14 +32,8 @@
 
 namespace GUI {
 
-GroupBox::GroupBox(Widget* parent)
-    : GroupBox({}, parent)
-{
-}
-
-GroupBox::GroupBox(const StringView& title, Widget* parent)
-    : Widget(parent)
-    , m_title(title)
+GroupBox::GroupBox(const StringView& title)
+    : m_title(title)
 {
 }
 

Libraries/LibGUI/GroupBox.h

@@ -39,8 +39,7 @@ public:
     void set_title(const StringView&);
 
 protected:
-    explicit GroupBox(Widget* parent = nullptr);
-    GroupBox(const StringView& title, Widget* parent = nullptr);
+    explicit GroupBox(const StringView& title = {});
 
     virtual void paint_event(PaintEvent&) override;
 

Libraries/LibGUI/ItemView.cpp

@@ -37,8 +37,7 @@
 
 namespace GUI {
 
-ItemView::ItemView(Widget* parent)
-    : AbstractView(parent)
+ItemView::ItemView()
 {
     set_background_role(ColorRole::Base);
     set_foreground_role(ColorRole::BaseText);

Libraries/LibGUI/ItemView.h

@@ -48,7 +48,7 @@ public:
     virtual ModelIndex index_at_event_position(const Gfx::Point&) const override;
 
 private:
-    explicit ItemView(Widget* parent = nullptr);
+    ItemView();
 
     virtual void did_update_model() override;
     virtual void paint_event(PaintEvent&) override;

Libraries/LibGUI/Label.cpp

@@ -32,14 +32,8 @@
 
 namespace GUI {
 
-Label::Label(Widget* parent)
-    : Label({}, parent)
-{
-}
-
-Label::Label(const StringView& text, Widget* parent)
-    : Frame(parent)
-    , m_text(text)
+Label::Label(const StringView& text)
+    : m_text(text)
 {
     set_frame_thickness(0);
     set_frame_shadow(Gfx::FrameShadow::Plain);

Libraries/LibGUI/Label.h

@@ -52,8 +52,7 @@ public:
     void size_to_fit();
 
 protected:
-    explicit Label(Widget* parent = nullptr);
-    Label(const StringView& text, Widget* parent = nullptr);
+    explicit Label(const StringView& text = {});
 
     virtual void paint_event(PaintEvent&) override;
 

Libraries/LibGUI/LazyWidget.cpp

@@ -28,8 +28,7 @@
 
 namespace GUI {
 
-LazyWidget::LazyWidget(Widget* parent)
-    : Widget(parent)
+LazyWidget::LazyWidget()
 {
 }
 

Libraries/LibGUI/LazyWidget.h

@@ -38,7 +38,7 @@ public:
     Function<void(LazyWidget&)> on_first_show;
 
 protected:
-    explicit LazyWidget(Widget* parent = nullptr);
+    LazyWidget();
 
 private:
     virtual void show_event(ShowEvent&) override;

Libraries/LibGUI/ListView.cpp

@@ -33,8 +33,7 @@
 
 namespace GUI {
 
-ListView::ListView(Widget* parent)
-    : AbstractView(parent)
+ListView::ListView()
 {
     set_background_role(ColorRole::Base);
     set_foreground_role(ColorRole::BaseText);

Libraries/LibGUI/ListView.h

@@ -33,7 +33,6 @@ namespace GUI {
 class ListView : public AbstractView {
     C_OBJECT(ListView)
 public:
-    explicit ListView(Widget* parent = nullptr);
     virtual ~ListView() override;
 
     int item_height() const { return 16; }
@@ -54,6 +53,8 @@ public:
     void set_model_column(int column) { m_model_column = column; }
 
 private:
+    ListView();
+
     virtual void did_update_model() override;
     virtual void paint_event(PaintEvent&) override;
     virtual void doubleclick_event(MouseEvent&) override;

Libraries/LibGUI/ModelEditingDelegate.h

@@ -77,7 +77,7 @@ public:
 
     virtual RefPtr<Widget> create_widget() override
     {
-        auto textbox = TextBox::construct(nullptr);
+        auto textbox = TextBox::construct();
         textbox->on_return_pressed = [this] {
             commit();
         };

Libraries/LibGUI/ProgressBar.cpp

@@ -32,8 +32,7 @@
 
 namespace GUI {
 
-ProgressBar::ProgressBar(Widget* parent)
-    : Frame(parent)
+ProgressBar::ProgressBar()
 {
 }
 

Libraries/LibGUI/ProgressBar.h

@@ -56,7 +56,7 @@ public:
     void set_format(Format format) { m_format = format; }
 
 protected:
-    explicit ProgressBar(Widget* parent = nullptr);
+    ProgressBar();
 
     virtual void paint_event(PaintEvent&) override;
 

Libraries/LibGUI/RadioButton.cpp

@@ -33,13 +33,8 @@
 
 namespace GUI {
 
-RadioButton::RadioButton(Widget* parent)
-    : RadioButton({}, parent)
-{
-}
-
-RadioButton::RadioButton(const StringView& text, Widget* parent)
-    : AbstractButton(text, parent)
+RadioButton::RadioButton(const StringView& text)
+    : AbstractButton(text)
 {
 }
 

Libraries/LibGUI/RadioButton.h

@@ -38,8 +38,7 @@ public:
     virtual void click() override;
 
 protected:
-    explicit RadioButton(Widget* parent = nullptr);
-    explicit RadioButton(const StringView& text, Widget* parent = nullptr);
+    explicit RadioButton(const StringView& text = {});
     virtual void paint_event(PaintEvent&) override;
 
 private:

Libraries/LibGUI/ResizeCorner.cpp

@@ -75,8 +75,7 @@ static Gfx::CharacterBitmap* s_resize_corner_highlights_bitmap;
 static const int s_resize_corner_bitmap_width = 16;
 static const int s_resize_corner_bitmap_height = 16;
 
-ResizeCorner::ResizeCorner(Widget* parent)
-    : Widget(parent)
+ResizeCorner::ResizeCorner()
 {
     set_background_role(ColorRole::Button);
     set_size_policy(SizePolicy::Fixed, SizePolicy::Fixed);

Libraries/LibGUI/ResizeCorner.h

@@ -34,7 +34,7 @@ public:
     virtual ~ResizeCorner() override;
 
 protected:
-    explicit ResizeCorner(Widget* parent = nullptr);
+    ResizeCorner();
 
     virtual void paint_event(PaintEvent&) override;
     virtual void mousedown_event(MouseEvent&) override;

Libraries/LibGUI/ScrollBar.cpp

@@ -86,14 +86,8 @@ static Gfx::CharacterBitmap* s_down_arrow_bitmap;
 static Gfx::CharacterBitmap* s_left_arrow_bitmap;
 static Gfx::CharacterBitmap* s_right_arrow_bitmap;
 
-ScrollBar::ScrollBar(Widget* parent)
-    : ScrollBar(Orientation::Vertical, parent)
-{
-}
-
-ScrollBar::ScrollBar(Orientation orientation, Widget* parent)
-    : Widget(parent)
-    , m_orientation(orientation)
+ScrollBar::ScrollBar(Orientation orientation)
+    : m_orientation(orientation)
 {
     m_automatic_scrolling_timer = add<Core::Timer>();
     if (!s_up_arrow_bitmap)

Libraries/LibGUI/ScrollBar.h

@@ -65,8 +65,7 @@ public:
     };
 
 private:
-    explicit ScrollBar(Widget* parent = nullptr);
-    explicit ScrollBar(Orientation, Widget* parent = nullptr);
+    explicit ScrollBar(Gfx::Orientation = Gfx::Orientation::Vertical);
 
     virtual void paint_event(PaintEvent&) override;
     virtual void mousedown_event(MouseEvent&) override;

Libraries/LibGUI/ScrollableWidget.cpp

@@ -29,17 +29,16 @@
 
 namespace GUI {
 
-ScrollableWidget::ScrollableWidget(Widget* parent)
-    : Frame(parent)
+ScrollableWidget::ScrollableWidget()
 {
-    m_vertical_scrollbar = ScrollBar::construct(Orientation::Vertical, this);
+    m_vertical_scrollbar = add<ScrollBar>(Orientation::Vertical);
     m_vertical_scrollbar->set_step(4);
     m_vertical_scrollbar->on_change = [this](int) {
         did_scroll();
         update();
     };
 
-    m_horizontal_scrollbar = ScrollBar::construct(Orientation::Horizontal, this);
+    m_horizontal_scrollbar = add<ScrollBar>(Orientation::Horizontal);
     m_horizontal_scrollbar->set_step(4);
     m_horizontal_scrollbar->set_big_step(30);
     m_horizontal_scrollbar->on_change = [this](int) {
@@ -47,7 +46,7 @@ ScrollableWidget::ScrollableWidget(Widget* parent)
         update();
     };
 
-    m_corner_widget = Widget::construct(this);
+    m_corner_widget = add<Widget>();
     m_corner_widget->set_fill_with_background_color(true);
 }
 

Libraries/LibGUI/ScrollableWidget.h

@@ -71,7 +71,7 @@ public:
     Gfx::Point to_widget_position(const Gfx::Point& content_position) const;
 
 protected:
-    explicit ScrollableWidget(Widget* parent = nullptr);
+    ScrollableWidget();
     virtual void custom_layout() override;
     virtual void resize_event(ResizeEvent&) override;
     virtual void mousewheel_event(MouseEvent&) override;

Libraries/LibGUI/Slider.cpp

@@ -33,14 +33,8 @@
 
 namespace GUI {
 
-Slider::Slider(Widget* parent)
-    : Slider(Orientation::Horizontal, parent)
-{
-}
-
-Slider::Slider(Orientation orientation, Widget* parent)
-    : Widget(parent)
-    , m_orientation(orientation)
+Slider::Slider(Orientation orientation)
+    : m_orientation(orientation)
 {
 }
 

Libraries/LibGUI/Slider.h

@@ -74,8 +74,7 @@ public:
     Function<void(int)> on_value_changed;
 
 protected:
-    explicit Slider(Widget* = nullptr);
-    explicit Slider(Orientation, Widget* = nullptr);
+    explicit Slider(Orientation = Orientation::Vertical);
 
     virtual void paint_event(PaintEvent&) override;
     virtual void mousedown_event(MouseEvent&) override;
@@ -106,8 +105,8 @@ public:
     virtual ~VerticalSlider() override {}
 
 private:
-    explicit VerticalSlider(Widget* parent = nullptr)
-        : Slider(Orientation::Vertical, parent)
+    VerticalSlider()
+        : Slider(Orientation::Vertical)
     {
     }
 };
@@ -118,8 +117,8 @@ public:
     virtual ~HorizontalSlider() override {}
 
 private:
-    explicit HorizontalSlider(Widget* parent = nullptr)
-        : Slider(Orientation::Horizontal, parent)
+    HorizontalSlider()
+        : Slider(Orientation::Horizontal)
     {
     }
 };

Libraries/LibGUI/SpinBox.cpp

@@ -30,8 +30,7 @@
 
 namespace GUI {
 
-SpinBox::SpinBox(Widget* parent)
-    : Widget(parent)
+SpinBox::SpinBox()
 {
     m_editor = add<TextBox>();
     m_editor->set_text("0");

Libraries/LibGUI/SpinBox.h

@@ -47,7 +47,7 @@ public:
     Function<void(int value)> on_change;
 
 protected:
-    explicit SpinBox(Widget* parent = nullptr);
+    SpinBox();
 
     virtual void resize_event(ResizeEvent&) override;
 

Libraries/LibGUI/Splitter.cpp

@@ -32,9 +32,8 @@
 
 namespace GUI {
 
-Splitter::Splitter(Orientation orientation, Widget* parent)
-    : Frame(parent)
-    , m_orientation(orientation)
+Splitter::Splitter(Orientation orientation)
+    : m_orientation(orientation)
 {
     set_background_role(ColorRole::Button);
     set_layout(make<BoxLayout>(orientation));

Libraries/LibGUI/Splitter.h

@@ -36,7 +36,7 @@ public:
     virtual ~Splitter() override;
 
 protected:
-    Splitter(Gfx::Orientation, Widget* parent = nullptr);
+    explicit Splitter(Gfx::Orientation);
 
     virtual void paint_event(PaintEvent&) override;
     virtual void resize_event(ResizeEvent&) override;
@@ -68,8 +68,8 @@ public:
     virtual ~VerticalSplitter() override {}
 
 private:
-    explicit VerticalSplitter(Widget* parent = nullptr)
-        : Splitter(Gfx::Orientation::Vertical, parent)
+    VerticalSplitter()
+        : Splitter(Gfx::Orientation::Vertical)
     {
     }
 };
@@ -80,8 +80,8 @@ public:
     virtual ~HorizontalSplitter() override {}
 
 private:
-    explicit HorizontalSplitter(Widget* parent = nullptr)
-        : Splitter(Gfx::Orientation::Horizontal, parent)
+    HorizontalSplitter()
+        : Splitter(Gfx::Orientation::Horizontal)
     {
     }
 };

Libraries/LibGUI/StackWidget.cpp

@@ -29,8 +29,7 @@
 
 namespace GUI {
 
-StackWidget::StackWidget(Widget* parent)
-    : Widget(parent)
+StackWidget::StackWidget()
 {
 }
 

Libraries/LibGUI/StackWidget.h

@@ -42,7 +42,7 @@ public:
     Function<void(Widget*)> on_active_widget_change;
 
 protected:
-    explicit StackWidget(Widget* parent = nullptr);
+    StackWidget();
     virtual void child_event(Core::ChildEvent&) override;
     virtual void resize_event(ResizeEvent&) override;
 

Libraries/LibGUI/StatusBar.cpp

@@ -34,13 +34,7 @@
 
 namespace GUI {
 
-StatusBar::StatusBar(Widget* parent)
-    : StatusBar(1, parent)
-{
-}
-
-StatusBar::StatusBar(int label_count, Widget* parent)
-    : Widget(parent)
+StatusBar::StatusBar(int label_count)
 {
     set_size_policy(SizePolicy::Fill, SizePolicy::Fixed);
     set_preferred_size(0, 20);
@@ -54,7 +48,7 @@ StatusBar::StatusBar(int label_count, Widget* parent)
     for (auto i = 0; i < label_count; i++)
         m_labels.append(create_label());
 
-    m_corner = ResizeCorner::construct(this);
+    m_corner = add<ResizeCorner>();
 }
 
 StatusBar::~StatusBar()
@@ -63,7 +57,7 @@ StatusBar::~StatusBar()
 
 NonnullRefPtr<Label> StatusBar::create_label()
 {
-    auto label = Label::construct(this);
+    auto label = add<Label>();
     label->set_frame_shadow(Gfx::FrameShadow::Sunken);
     label->set_frame_shape(Gfx::FrameShape::Panel);
     label->set_frame_thickness(1);

Libraries/LibGUI/StatusBar.h

@@ -41,8 +41,7 @@ public:
     void set_text(int index, const StringView&);
 
 protected:
-    explicit StatusBar(Widget* parent = nullptr);
-    explicit StatusBar(int label_count, Widget* parent = nullptr);
+    explicit StatusBar(int label_count = 1);
     virtual void paint_event(PaintEvent&) override;
 
 private:

Libraries/LibGUI/TabWidget.cpp

@@ -33,8 +33,7 @@
 
 namespace GUI {
 
-TabWidget::TabWidget(Widget* parent)
-    : Widget(parent)
+TabWidget::TabWidget()
 {
 }
 

Libraries/LibGUI/TabWidget.h

@@ -38,7 +38,6 @@ public:
         Bottom,
     };
 
-    explicit TabWidget(Widget* parent = nullptr);
     virtual ~TabWidget() override;
 
     TabPosition tab_position() const { return m_tab_position; }
@@ -56,6 +55,8 @@ public:
     void add_widget(const StringView&, Widget*);
 
 protected:
+    TabWidget();
+
     virtual void paint_event(PaintEvent&) override;
     virtual void child_event(Core::ChildEvent&) override;
     virtual void resize_event(ResizeEvent&) override;

Libraries/LibGUI/TableView.cpp

@@ -38,8 +38,7 @@
 
 namespace GUI {
 
-TableView::TableView(Widget* parent)
-    : AbstractTableView(parent)
+TableView::TableView()
 {
     set_background_role(ColorRole::Base);
     set_foreground_role(ColorRole::BaseText);

Libraries/LibGUI/TableView.h

@@ -36,7 +36,7 @@ public:
     virtual ~TableView() override;
 
 protected:
-    explicit TableView(Widget* parent = nullptr);
+    TableView();
 
     virtual void paint_event(PaintEvent&) override;
 };

Libraries/LibGUI/TextBox.cpp

@@ -28,8 +28,8 @@
 
 namespace GUI {
 
-TextBox::TextBox(Widget* parent)
-    : TextEditor(TextEditor::SingleLine, parent)
+TextBox::TextBox()
+    : TextEditor(TextEditor::SingleLine)
 {
 }
 

Libraries/LibGUI/TextBox.h

@@ -33,7 +33,7 @@ namespace GUI {
 class TextBox : public TextEditor {
     C_OBJECT(TextBox)
 public:
-    explicit TextBox(Widget* parent = nullptr);
+    TextBox();
     virtual ~TextBox() override;
 };
 

Libraries/LibGUI/TextEditor.cpp

@@ -49,14 +49,8 @@
 
 namespace GUI {
 
-TextEditor::TextEditor(Widget* parent)
-    : TextEditor(Type::MultiLine, parent)
-{
-}
-
-TextEditor::TextEditor(Type type, Widget* parent)
-    : ScrollableWidget(parent)
-    , m_type(type)
+TextEditor::TextEditor(Type type)
+    : m_type(type)
 {
     set_background_role(ColorRole::Base);
     set_foreground_role(ColorRole::BaseText);

Libraries/LibGUI/TextEditor.h

@@ -130,8 +130,7 @@ public:
     void set_syntax_highlighter(OwnPtr<SyntaxHighlighter>);
 
 protected:
-    explicit TextEditor(Widget* parent = nullptr);
-    explicit TextEditor(Type, Widget* parent = nullptr);
+    explicit TextEditor(Type = Type::MultiLine);
 
     virtual void did_change_font() override;
     virtual void paint_event(PaintEvent&) override;

Libraries/LibGUI/ToolBar.cpp

@@ -34,14 +34,8 @@
 
 namespace GUI {
 
-ToolBar::ToolBar(Widget* parent)
-    : ToolBar(Orientation::Horizontal, 16, parent)
-{
-}
-
-ToolBar::ToolBar(Orientation orientation, int button_size, Widget* parent)
-    : Widget(parent)
-    , m_button_size(button_size)
+ToolBar::ToolBar(Orientation orientation, int button_size)
+    : m_button_size(button_size)
 {
     if (orientation == Orientation::Horizontal) {
         set_size_policy(SizePolicy::Fill, SizePolicy::Fixed);
@@ -87,8 +81,7 @@ void ToolBar::add_action(Action& action)
 class SeparatorWidget final : public Widget {
     C_OBJECT(SeparatorWidget)
 public:
-    SeparatorWidget(Widget* parent)
-        : Widget(parent)
+    SeparatorWidget()
     {
         set_size_policy(SizePolicy::Fixed, SizePolicy::Fixed);
         set_preferred_size(8, 22);
@@ -109,7 +102,7 @@ void ToolBar::add_separator()
 {
     auto item = make<Item>();
     item->type = Item::Type::Separator;
-    new SeparatorWidget(this);
+    add<SeparatorWidget>();
     m_items.append(move(item));
 }
 

Libraries/LibGUI/ToolBar.h

@@ -43,8 +43,7 @@ public:
     void set_has_frame(bool has_frame) { m_has_frame = has_frame; }
 
 protected:
-    explicit ToolBar(Widget* parent = nullptr);
-    explicit ToolBar(Orientation, int button_size, Widget* parent = nullptr);
+    explicit ToolBar(Gfx::Orientation = Gfx::Orientation::Horizontal, int button_size = 16);
 
     virtual void paint_event(PaintEvent&) override;
 

Libraries/LibGUI/TreeView.cpp

@@ -51,8 +51,7 @@ TreeView::MetadataForIndex& TreeView::ensure_metadata_for_index(const ModelIndex
     return new_metadata_ref;
 }
 
-TreeView::TreeView(Widget* parent)
-    : AbstractTableView(parent)
+TreeView::TreeView()
 {
     set_background_role(ColorRole::Base);
     set_foreground_role(ColorRole::BaseText);

Libraries/LibGUI/TreeView.h

@@ -41,7 +41,7 @@ public:
     virtual int item_count() const override;
 
 protected:
-    explicit TreeView(Widget* parent = nullptr);
+    TreeView();
 
     virtual void paint_event(PaintEvent&) override;
     virtual void doubleclick_event(MouseEvent&) override;

Libraries/LibGUI/Widget.cpp

@@ -70,7 +70,7 @@ static HashMap<String, WidgetClassRegistration*>& widget_classes()
     return *map;
 }
 
-WidgetClassRegistration::WidgetClassRegistration(const String& class_name, Function<NonnullRefPtr<Widget>(Widget*)> factory)
+WidgetClassRegistration::WidgetClassRegistration(const String& class_name, Function<NonnullRefPtr<Widget>()> factory)
     : m_class_name(class_name)
     , m_factory(move(factory))
 {
@@ -93,8 +93,8 @@ const WidgetClassRegistration* WidgetClassRegistration::find(const String& class
     return widget_classes().get(class_name).value_or(nullptr);
 }
 
-Widget::Widget(Widget* parent)
-    : Core::Object(parent, true)
+Widget::Widget()
+    : Core::Object(nullptr, true)
     , m_background_role(Gfx::ColorRole::Window)
     , m_foreground_role(Gfx::ColorRole::WindowText)
     , m_font(Gfx::Font::default_font())

Libraries/LibGUI/Widget.h

@@ -37,7 +37,7 @@
 
 #define REGISTER_GWIDGET(class_name)                          \
     extern WidgetClassRegistration registration_##class_name; \
-    WidgetClassRegistration registration_##class_name(#class_name, [](Widget* parent) { return class_name::construct(parent); });
+    WidgetClassRegistration registration_##class_name(#class_name, []() { return class_name::construct(); });
 
 template<>
 inline bool Core::is<GUI::Widget>(const Core::Object& object)
@@ -75,18 +75,18 @@ class WidgetClassRegistration {
     AK_MAKE_NONCOPYABLE(WidgetClassRegistration)
     AK_MAKE_NONMOVABLE(WidgetClassRegistration)
 public:
-    WidgetClassRegistration(const String& class_name, Function<NonnullRefPtr<Widget>(Widget*)> factory);
+    WidgetClassRegistration(const String& class_name, Function<NonnullRefPtr<Widget>()> factory);
     ~WidgetClassRegistration();
 
     String class_name() const { return m_class_name; }
-    NonnullRefPtr<Widget> construct(Widget* parent) const { return m_factory(parent); }
+    NonnullRefPtr<Widget> construct() const { return m_factory(); }
 
     static void for_each(Function<void(const WidgetClassRegistration&)>);
     static const WidgetClassRegistration* find(const String& class_name);
 
 private:
     String m_class_name;
-    Function<NonnullRefPtr<Widget>(Widget*)> m_factory;
+    Function<NonnullRefPtr<Widget>()> m_factory;
 };
 
 class Widget : public Core::Object {
@@ -259,7 +259,7 @@ public:
     void set_palette(const Gfx::Palette&);
 
 protected:
-    explicit Widget(Widget* parent = nullptr);
+    Widget();
 
     virtual void custom_layout() {}
     virtual void did_change_font() {}