ui/views/controls/throbber.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_VIEWS_CONTROLS_THROBBER_H_
   6 #define UI_VIEWS_CONTROLS_THROBBER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/compiler_specific.h"
  10 #include "base/time/time.h"
  11 #include "base/timer/timer.h"
  12 #include "ui/views/view.h"
  13
  14 namespace gfx {
  15 class ImageSkia;
  16 }
  17
  18 namespace views {
  19
  20 // Throbbers display an animation, usually used as a status indicator.
  21
  22 class VIEWS_EXPORT Throbber : public View {
  23  public:
  24   // |frame_time_ms| is the amount of time that should elapse between frames
  25   //                 (in milliseconds)
  26   // If |paint_while_stopped| is false, this view will be invisible when not
  27   // running.
  28   Throbber(int frame_time_ms, bool paint_while_stopped);
  29   Throbber(int frame_time_ms, bool paint_while_stopped, gfx::ImageSkia* frames);
  30   ~Throbber() override;
  31
  32   // Start and stop the throbber animation
  33   virtual void Start();
  34   virtual void Stop();
  35
  36   // Set custom throbber frames. Otherwise IDR_THROBBER is loaded.
  37   void SetFrames(const gfx::ImageSkia* frames);
  38
  39   // Overridden from View:
  40   gfx::Size GetPreferredSize() const override;
  41   void OnPaint(gfx::Canvas* canvas) override;
  42
  43  protected:
  44   bool running() const { return running_; }
  45   base::Time start_time() const { return start_time_; }
  46
  47   // Specifies whether the throbber is currently animating or not
  48
  49  private:
  50   void Run();
  51
  52   bool running_;
  53   bool paint_while_stopped_;
  54   int frame_count_;  // How many frames we have.
  55   base::Time start_time_;  // Time when Start was called.
  56   const gfx::ImageSkia* frames_;  // Frames images.
  57   base::TimeDelta frame_time_;  // How long one frame is displayed.
  58   base::RepeatingTimer<Throbber> timer_;  // Used to schedule Run calls.
  59
  60   DISALLOW_COPY_AND_ASSIGN(Throbber);
  61 };
  62
  63 // A SmoothedThrobber is a throbber that is representing potentially short
  64 // and nonoverlapping bursts of work.  SmoothedThrobber ignores small
  65 // pauses in the work stops and starts, and only starts its throbber after
  66 // a small amount of work time has passed.
  67 class VIEWS_EXPORT SmoothedThrobber : public Throbber {
  68  public:
  69   explicit SmoothedThrobber(int frame_delay_ms);
  70   SmoothedThrobber(int frame_delay_ms, gfx::ImageSkia* frames);
  71   ~SmoothedThrobber() override;
  72
  73   void Start() override;
  74   void Stop() override;
  75
  76   void set_start_delay_ms(int value) { start_delay_ms_ = value; }
  77   void set_stop_delay_ms(int value) { stop_delay_ms_ = value; }
  78
  79  private:
  80   // Called when the startup-delay timer fires
  81   // This function starts the actual throbbing.
  82   void StartDelayOver();
  83
  84   // Called when the shutdown-delay timer fires.
  85   // This function stops the actual throbbing.
  86   void StopDelayOver();
  87
  88   // Delay after work starts before starting throbber, in milliseconds.
  89   int start_delay_ms_;
  90
  91   // Delay after work stops before stopping, in milliseconds.
  92   int stop_delay_ms_;
  93
  94   base::OneShotTimer<SmoothedThrobber> start_timer_;
  95   base::OneShotTimer<SmoothedThrobber> stop_timer_;
  96
  97   DISALLOW_COPY_AND_ASSIGN(SmoothedThrobber);
  98 };
  99
 100 // A throbber that follows material design guidelines. This is a specialization
 101 // of Throbber for now, but should probably be folded into/replace Throbber
 102 // eventually.
 103 class VIEWS_EXPORT MaterialThrobber : public Throbber {
 104  public:
 105   MaterialThrobber();
 106   ~MaterialThrobber() override;
 107
 108   // Stop spinning and, if checked is true, display a checkmark.
 109   void SetChecked(bool checked);
 110
 111   void set_preferred_diameter(int diameter) { preferred_diameter_ = diameter; }
 112
 113   // View implementation.
 114   gfx::Size GetPreferredSize() const override;
 115   int GetHeightForWidth(int w) const override;
 116   void OnPaint(gfx::Canvas* canvas) override;
 117
 118  private:
 119   // The preferred width and height for this view. Zero indicates the size is
 120   // set by the parent class (i.e. matches the size of the pre-material
 121   // sprites).
 122   int preferred_diameter_;
 123
 124   // Whether or not we should display a checkmark.
 125   bool checked_;
 126
 127   // The checkmark image. Will be null until it's used (if ever).
 128   const gfx::ImageSkia* checkmark_;
 129
 130   DISALLOW_COPY_AND_ASSIGN(MaterialThrobber);
 131 };
 132
 133 }  // namespace views
 134
 135 #endif  // UI_VIEWS_CONTROLS_THROBBER_H_