Create a unified UIElement interface for Widget, View and Window.

ash/devtools/ui_element.h

Index: ash/devtools/ui_element.h
diff --git a/ash/devtools/ui_element.h b/ash/devtools/ui_element.h
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+// Copyright 2017 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 ASH_DEVTOOLS_UI_ELEMENT_H_
+#define ASH_DEVTOOLS_UI_ELEMENT_H_
+
+#include <vector>
+
+#include "ash/ash_export.h"
+#include "base/macros.h"
+#include "ui/aura/window.h"
+#include "ui/gfx/geometry/rect.h"
+#include "ui/views/view.h"
+
+namespace ash {
+namespace devtools {
+
+class UIElementDelegate;
+
+// UIElement type.
+enum UIElementType { WINDOW, WIDGET, VIEW };
+
+class ASH_EXPORT UIElement {
+ public:
+  virtual ~UIElement();
+  int node_id() const { return node_id_; };
+  std::string GetTypeName() const;
+  UIElement* parent() const { return parent_; };
+  UIElementDelegate* delegate() const { return delegate_; };
+  UIElementType type() const { return type_; };
+  const std::vector<UIElement*>& children() const { return children_; };
+
+  // |child| is inserted in front of |before|. If |before| is null, it
+  // is inserted at the end. Parent takes ownership of the added child.
+  void AddChild(UIElement* child, UIElement* before = nullptr);
+
+  // Remove |child| out of vector |children_| but |child| is not destroyed.
+  // The caller is responsible for destroying |child|.
+  void RemoveChild(UIElement* child);
+
+  // Move |child| to position new_index in |children_|.
+  void ReorderChild(UIElement* child, int new_index);
+
+  virtual void GetBounds(gfx::Rect* bounds) const = 0;
+  virtual void SetBounds(const gfx::Rect& bounds) = 0;
+  virtual void GetVisible(bool* visible) const = 0;
+  virtual void SetVisible(bool visible) = 0;
+
+  // If element exists, return its associated native window and its bounds.
+  // Otherwise, return null and empty bounds.
+  virtual std::pair<aura::Window*, gfx::Rect> GetNodeWindowAndBounds()
+      const = 0;
+
+  template <typename BackingT, typename T>
+  static BackingT* GetBackingElement(UIElement* element) {
+    return T::From(element);
+  };
+
+ protected:
+  UIElement(const UIElementType type,
+            UIElementDelegate* delegate,
+            UIElement* parent);
+
+ private:
+  const int node_id_;
+  const UIElementType type_;
+  std::vector<UIElement*> children_;
+  UIElement* parent_;
+  UIElementDelegate* delegate_;
+
+  DISALLOW_COPY_AND_ASSIGN(UIElement);
+};
+
+}  // namespace devtools
+}  // namespace ash
+
+#endif  // ASH_DEVTOOLS_UI_ELEMENT_H_