MouseSettings: Give this application a GUI facelift :^)

Note that the double-click "icon" adapts to the double-click speed
and also reacts to double-clicks. :^)

Userland/Applications/MouseSettings/DoubleClickArrowWidget.cpp

@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "DoubleClickArrowWidget.h"
+#include <LibGUI/Painter.h>
+#include <LibGfx/Font.h>
+
+REGISTER_WIDGET(MouseSettings, DoubleClickArrowWidget);
+
+namespace MouseSettings {
+
+DoubleClickArrowWidget::~DoubleClickArrowWidget()
+{
+}
+
+void DoubleClickArrowWidget::set_double_click_speed(int speed)
+{
+    if (m_double_click_speed == speed)
+        return;
+    m_double_click_speed = speed;
+    update();
+}
+
+DoubleClickArrowWidget::DoubleClickArrowWidget()
+{
+    m_arrow_bitmap = Gfx::Bitmap::load_from_file("/res/graphics/double-click-down-arrow.png");
+}
+
+void DoubleClickArrowWidget::paint_event(GUI::PaintEvent& event)
+{
+    GUI::Painter painter(*this);
+    painter.add_clip_rect(event.rect());
+
+    auto bottom_arrow_rect = m_arrow_bitmap->rect();
+    bottom_arrow_rect.center_within(rect());
+    bottom_arrow_rect.translate_by(0, m_arrow_bitmap->height() / 2);
+
+    painter.blit_filtered(bottom_arrow_rect.location(), *m_arrow_bitmap, m_arrow_bitmap->rect(), [&](Color color) {
+        return m_inverted ? color.inverted() : color;
+    });
+
+    auto top_arrow_rect = bottom_arrow_rect;
+    top_arrow_rect.translate_by(0, -(m_double_click_speed / 50));
+
+    painter.blit_filtered(top_arrow_rect.location(), *m_arrow_bitmap, m_arrow_bitmap->rect(), [&](Color color) {
+        return m_inverted ? color.inverted() : color;
+    });
+
+    auto text_rect = rect();
+    text_rect.set_y(bottom_arrow_rect.bottom());
+    text_rect.set_height(font().glyph_height());
+}
+
+void DoubleClickArrowWidget::doubleclick_event(GUI::MouseEvent&)
+{
+    m_inverted = !m_inverted;
+    update();
+}
+
+}