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   // Specifies whether the throbber is currently animating or not
  45   bool IsRunning() const;
  46   base::TimeTicks start_time() const { return start_time_; }
  47
  48  private:
  49   bool paint_while_stopped_;
  50   int frame_count_;  // How many frames we have.
  51   base::TimeTicks start_time_;  // Time when Start was called.
  52   const gfx::ImageSkia* frames_;  // Frames images.
  53   base::TimeDelta frame_time_;  // How long one frame is displayed.
  54   base::RepeatingTimer<Throbber> timer_;  // Used to schedule Run calls.
  55
  56   DISALLOW_COPY_AND_ASSIGN(Throbber);
  57 };
  58
  59 // A SmoothedThrobber is a throbber that is representing potentially short
  60 // and nonoverlapping bursts of work.  SmoothedThrobber ignores small
  61 // pauses in the work stops and starts, and only starts its throbber after
  62 // a small amount of work time has passed.
  63 class VIEWS_EXPORT SmoothedThrobber : public Throbber {
  64  public:
  65   explicit SmoothedThrobber(int frame_delay_ms);
  66   SmoothedThrobber(int frame_delay_ms, gfx::ImageSkia* frames);
  67   ~SmoothedThrobber() override;
  68
  69   void Start() override;
  70   void Stop() override;
  71
  72   void set_start_delay_ms(int value) { start_delay_ms_ = value; }
  73   void set_stop_delay_ms(int value) { stop_delay_ms_ = value; }
  74
  75  private:
  76   // Called when the startup-delay timer fires
  77   // This function starts the actual throbbing.
  78   void StartDelayOver();
  79
  80   // Called when the shutdown-delay timer fires.
  81   // This function stops the actual throbbing.
  82   void StopDelayOver();
  83
  84   // Delay after work starts before starting throbber, in milliseconds.
  85   int start_delay_ms_;
  86
  87   // Delay after work stops before stopping, in milliseconds.
  88   int stop_delay_ms_;
  89
  90   base::OneShotTimer<SmoothedThrobber> start_timer_;
  91   base::OneShotTimer<SmoothedThrobber> stop_timer_;
  92
  93   DISALLOW_COPY_AND_ASSIGN(SmoothedThrobber);
  94 };
  95
  96 // A throbber that follows material design guidelines. This is a specialization
  97 // of Throbber for now, but should probably be folded into/replace Throbber
  98 // eventually.
  99 class VIEWS_EXPORT MaterialThrobber : public Throbber {
 100  public:
 101   MaterialThrobber();
 102   ~MaterialThrobber() override;
 103
 104   // Stop spinning and, if checked is true, display a checkmark.
 105   void SetChecked(bool checked);
 106
 107   void set_preferred_diameter(int diameter) { preferred_diameter_ = diameter; }
 108
 109   // View implementation.
 110   gfx::Size GetPreferredSize() const override;
 111   int GetHeightForWidth(int w) const override;
 112   void OnPaint(gfx::Canvas* canvas) override;
 113
 114  private:
 115   // The preferred width and height for this view. Zero indicates the size is
 116   // set by the parent class (i.e. matches the size of the pre-material
 117   // sprites).
 118   int preferred_diameter_;
 119
 120   // Whether or not we should display a checkmark.
 121   bool checked_;
 122
 123   // The checkmark image. Will be null until it's used (if ever).
 124   const gfx::ImageSkia* checkmark_;
 125
 126   DISALLOW_COPY_AND_ASSIGN(MaterialThrobber);
 127 };
 128
 129 }  // namespace views
 130
 131 #endif  // UI_VIEWS_CONTROLS_THROBBER_H_