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 class ActivityView;
  25
  26 // The view model for the representation of the activity.
  27 class ATHENA_EXPORT ActivityViewModel {
  28  public:
  29   virtual ~ActivityViewModel() {}
  30
  31   // Called after the view model is attached to the widget/window tree and
  32   // before it gets registered to the ActivityManager and the ResourceManager.
  33   // At this time the Activity can also be moved to a different place in the
  34   // Activity history.
  35   virtual void Init() = 0;
  36
  37   // Returns a color most representative of this activity.
  38   virtual SkColor GetRepresentativeColor() const = 0;
  39
  40   // Returns a title for the activity.
  41   virtual base::string16 GetTitle() const = 0;
  42
  43   // Returns an icon for the activity.
  44   virtual gfx::ImageSkia GetIcon() const = 0;
  45
  46   // Sets the ActivityView for the model to update. The model does not take
  47   // ownership of the view.
  48   virtual void SetActivityView(ActivityView* view) = 0;
  49
  50   // True if the activity wants to use Widget's frame, or false if the activity
  51   // draws its own frame.
  52   virtual bool UsesFrame() const = 0;
  53
  54   // Returns the contents view which might be nullptr if the activity is not
  55   // loaded. Note that the caller should not hold on to the view since it can
  56   // be deleted by the resource manager.
  57   virtual views::View* GetContentsView() = 0;
  58
  59   // Returns an image which can be used to represent the activity in e.g. the
  60   // overview mode. The returned image can have no size if either a view exists
  61   // or the activity has not yet been loaded or ever been presented. In that
  62   // case GetRepresentativeColor() should be used to clear the preview area.
  63   // Note that since the image gets created upon request, and the
  64   // ActivityViewModel will hold no reference to the returned image data. As
  65   // such it is advisable to hold on to the image as long as needed instead of
  66   // calling this function frequently since it will cause time to generate.
  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_