ui/base/models/combobox_model.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_BASE_MODELS_COMBOBOX_MODEL_H_
   6 #define UI_BASE_MODELS_COMBOBOX_MODEL_H_
   7
   8 #include "base/strings/string16.h"
   9 #include "ui/base/ui_base_export.h"
  10
  11 namespace ui {
  12
  13 class ComboboxModelObserver;
  14
  15 // A data model for a combo box.
  16 class UI_BASE_EXPORT ComboboxModel {
  17  public:
  18   // Returns the number of items in the combo box.
  19   virtual int GetItemCount() const = 0;
  20
  21   // Returns the string at the specified index.
  22   virtual base::string16 GetItemAt(int index) = 0;
  23
  24   // Should return true if the item at |index| is a non-selectable separator
  25   // item.
  26   virtual bool IsItemSeparatorAt(int index);
  27
  28   // The index of the item that is selected by default (before user
  29   // interaction).
  30   virtual int GetDefaultIndex() const;
  31
  32   // Returns true if the item at |index| is enabled.
  33   virtual bool IsItemEnabledAt(int index) const;
  34
  35   // Adds/removes an observer. Override if model supports mutation.
  36   virtual void AddObserver(ComboboxModelObserver* observer) {}
  37   virtual void RemoveObserver(ComboboxModelObserver* observer) {}
  38
  39  protected:
  40   virtual ~ComboboxModel() {}
  41 };
  42
  43 }  // namespace ui
  44
  45 #endif  // UI_BASE_MODELS_COMBOBOX_MODEL_H_