views/examples: Add ProgressBar example.

views/examples/progress_bar_example.h

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef VIEWS_EXAMPLES_PROGRESS_BAR_EXAMPLE_H_
+#define VIEWS_EXAMPLES_PROGRESS_BAR_EXAMPLE_H_
+#pragma once
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "views/controls/button/button.h"
+#include "views/examples/example_base.h"
+
+namespace views {
+class ProgressBar;
+}
+
+namespace examples {
+
+class ProgressBarExample : public ExampleBase,
+                           public views::ButtonListener {
+ public:
+  explicit ProgressBarExample(ExamplesMain* main);
+  virtual ~ProgressBarExample();
+
+  // Overridden from ExampleBase:
+  virtual void CreateExampleView(views::View* container) OVERRIDE;
+
+ private:
+  // Overridden from views::ButtonListener:
+  virtual void ButtonPressed(views::Button* button,
+                             const views::Event& event) OVERRIDE;
+
+  views::Button* minus_button_;
+  views::Button* plus_button_;
+  views::ProgressBar* progress_bar_;
+  double current_percent_;
+
+  DISALLOW_COPY_AND_ASSIGN(ProgressBarExample);
+};
+
+}  // namespace examples
+
+#endif  // VIEWS_EXAMPLES_PROGRESS_BAR_EXAMPLE_H_