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diff --git a/Userland/Libraries/LibGUI/ScrollBar.h b/Userland/Libraries/LibGUI/ScrollBar.h
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+++ b/Userland/Libraries/LibGUI/ScrollBar.h
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+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <AK/Function.h>
+#include <LibGUI/AbstractSlider.h>
+
+namespace GUI {
+
+class ScrollBar final : public AbstractSlider {
+    C_OBJECT(ScrollBar);
+
+public:
+    virtual ~ScrollBar() override;
+
+    bool is_scrollable() const { return max() != min(); }
+
+    bool has_scrubber() const;
+
+    enum Component {
+        None,
+        DecrementButton,
+        IncrementButton,
+        Gutter,
+        Scrubber,
+    };
+
+private:
+    explicit ScrollBar(Gfx::Orientation = Gfx::Orientation::Vertical);
+
+    virtual void paint_event(PaintEvent&) override;
+    virtual void mousedown_event(MouseEvent&) override;
+    virtual void mouseup_event(MouseEvent&) override;
+    virtual void mousemove_event(MouseEvent&) override;
+    virtual void mousewheel_event(MouseEvent&) override;
+    virtual void leave_event(Core::Event&) override;
+    virtual void change_event(Event&) override;
+
+    int default_button_size() const { return 16; }
+    int button_size() const { return length(orientation()) <= (default_button_size() * 2) ? length(orientation()) / 2 : default_button_size(); }
+    int button_width() const { return orientation() == Orientation::Vertical ? width() : button_size(); }
+    int button_height() const { return orientation() == Orientation::Horizontal ? height() : button_size(); }
+    Gfx::IntRect decrement_button_rect() const;
+    Gfx::IntRect increment_button_rect() const;
+    Gfx::IntRect decrement_gutter_rect() const;
+    Gfx::IntRect increment_gutter_rect() const;
+    Gfx::IntRect scrubber_rect() const;
+    int unclamped_scrubber_size() const;
+    int visible_scrubber_size() const;
+    int scrubbable_range_in_pixels() const;
+    void on_automatic_scrolling_timer_fired();
+    void set_automatic_scrolling_active(bool, Component);
+
+    void scroll_to_position(const Gfx::IntPoint&);
+    void scroll_by_page(const Gfx::IntPoint&);
+
+    Component component_at_position(const Gfx::IntPoint&);
+
+    int m_scrub_start_value { 0 };
+    Gfx::IntPoint m_scrub_origin;
+
+    Component m_hovered_component { Component::None };
+    Component m_pressed_component { Component::None };
+    Gfx::IntPoint m_last_mouse_position;
+
+    RefPtr<Core::Timer> m_automatic_scrolling_timer;
+};
+
+}