Start working on a Widgets library.

Widgets/Widget.cpp

@@ -0,0 +1,76 @@
+#include "Widget.h"
+#include "Event.h"
+#include "EventLoop.h"
+#include <AK/Assertions.h>
+
+Widget::Widget(Widget* parent)
+    : Object(parent)
+{
+}
+
+Widget::~Widget()
+{
+}
+
+void Widget::event(Event& event)
+{
+    switch (event.type()) {
+    case Event::Paint:
+        return onPaint(static_cast<PaintEvent&>(event));
+    case Event::Show:
+        return onShow(static_cast<ShowEvent&>(event));
+    case Event::Hide:
+        return onHide(static_cast<HideEvent&>(event));
+    case Event::KeyDown:
+        return onKeyDown(static_cast<KeyEvent&>(event));
+    case Event::KeyUp:
+        return onKeyUp(static_cast<KeyEvent&>(event));
+    case Event::MouseMove:
+        return onMouseMove(static_cast<MouseEvent&>(event));
+    case Event::MouseDown:
+        return onMouseDown(static_cast<MouseEvent&>(event));
+    case Event::MouseUp:
+        return onMouseUp(static_cast<MouseEvent&>(event));
+    default:
+        return Object::event(event);
+    }
+}
+
+void Widget::onPaint(PaintEvent&)
+{
+}
+
+void Widget::onShow(ShowEvent&)
+{
+    update();
+}
+
+void Widget::onHide(HideEvent&)
+{
+}
+
+void Widget::onKeyDown(KeyEvent&)
+{
+}
+
+void Widget::onKeyUp(KeyEvent&)
+{
+}
+
+void Widget::onMouseDown(MouseEvent&)
+{
+}
+
+void Widget::onMouseUp(MouseEvent&)
+{
+}
+
+void Widget::onMouseMove(MouseEvent&)
+{
+}
+
+void Widget::update()
+{
+    EventLoop::main().postEvent(this, make<PaintEvent>());
+}
+