athena/activity/public/activity_view_model.h

   1 // Copyright 2014 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 ATHENA_ACTIVITY_PUBLIC_ACTIVITY_VIEW_MODEL_H_
   6 #define ATHENA_ACTIVITY_PUBLIC_ACTIVITY_VIEW_MODEL_H_
   7
   8 #include "athena/athena_export.h"
   9 #include "base/strings/string16.h"
  10
  11 typedef unsigned int SkColor;
  12
  13 namespace gfx {
  14 class ImageSkia;
  15 }
  16
  17 namespace views {
  18 class View;
  19 class Widget;
  20 }
  21
  22 namespace athena {
  23
  24 // The view model for the representation of the activity.
  25 class ATHENA_EXPORT ActivityViewModel {
  26  public:
  27   virtual ~ActivityViewModel() {}
  28
  29   // Called after the view model is attached to the widget/window tree and
  30   // before it gets registered to the ActivityManager and the ResourceManager.
  31   // At this time the Activity can also be moved to a different place in the
  32   // Activity history.
  33   virtual void Init() = 0;
  34
  35   // Returns a color most representative of this activity.
  36   virtual SkColor GetRepresentativeColor() const = 0;
  37
  38   // Returns a title for the activity.
  39   virtual base::string16 GetTitle() const = 0;
  40
  41   // Returns an icon for the activity.
  42   virtual gfx::ImageSkia GetIcon() const = 0;
  43
  44   // True if the activity wants to use Widget's frame, or false if the activity
  45   // draws its own frame.
  46   virtual bool UsesFrame() const = 0;
  47
  48   // Returns the contents view which might be NULL if the activity is not
  49   // loaded. Note that the caller should not hold on to the view since it can
  50   // be deleted by the resource manager.
  51   virtual views::View* GetContentsView() = 0;
  52
  53   // Creates a custom widget for the activity. Returns NULL to use default
  54   // implementation.
  55   virtual views::Widget* CreateWidget() = 0;
  56
  57   // This gets called before the Activity gets (partially) thrown out of memory
  58   // to create a preview image of the activity. Note that even if this function
  59   // gets called, |GetOverviewModeImage()| could still return an empty image.
  60   virtual void CreateOverviewModeImage() = 0;
  61
  62   // Returns an image which can be used to represent the activity in e.g. the
  63   // overview mode. The returned image can have no size if either a view exists
  64   // or the activity has not yet been loaded. In that case
  65   // GetRepresentativeColor() should be used to clear the preview area.
  66   // Note: We intentionally do not use a layer / view for this.
  67   virtual gfx::ImageSkia GetOverviewModeImage() = 0;
  68
  69   // Prepares the contents view for overview.
  70   virtual void PrepareContentsForOverview() = 0;
  71
  72   // Undoes any changes done by PrepareContentsForOverview().
  73   virtual void ResetContentsView() = 0;
  74 };
  75
  76 }  // namespace athena
  77
  78 #endif  // ATHENA_ACTIVITY_PUBLIC_ACTIVITY_VIEW_MODEL_H_