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 views {
  15
  16 // Throbbers display an animation, usually used as a status indicator.
  17
  18 class VIEWS_EXPORT Throbber : public View {
  19  public:
  20   Throbber();
  21   ~Throbber() override;
  22
  23   // Start and stop the throbber animation.
  24   virtual void Start();
  25   virtual void Stop();
  26
  27   // Stop spinning and, if checked is true, display a checkmark.
  28   void SetChecked(bool checked);
  29
  30   // Overridden from View:
  31   gfx::Size GetPreferredSize() const override;
  32   void OnPaint(gfx::Canvas* canvas) override;
  33
  34  protected:
  35   // Specifies whether the throbber is currently animating or not
  36   bool IsRunning() const;
  37
  38  private:
  39   base::TimeTicks start_time_;  // Time when Start was called.
  40   base::RepeatingTimer<Throbber> timer_;  // Used to schedule Run calls.
  41
  42   // Whether or not we should display a checkmark.
  43   bool checked_;
  44
  45   DISALLOW_COPY_AND_ASSIGN(Throbber);
  46 };
  47
  48 // A SmoothedThrobber is a throbber that is representing potentially short
  49 // and nonoverlapping bursts of work.  SmoothedThrobber ignores small
  50 // pauses in the work stops and starts, and only starts its throbber after
  51 // a small amount of work time has passed.
  52 class VIEWS_EXPORT SmoothedThrobber : public Throbber {
  53  public:
  54   SmoothedThrobber();
  55   ~SmoothedThrobber() override;
  56
  57   void Start() override;
  58   void Stop() override;
  59
  60   void set_start_delay_ms(int value) { start_delay_ms_ = value; }
  61   void set_stop_delay_ms(int value) { stop_delay_ms_ = value; }
  62
  63  private:
  64   // Called when the startup-delay timer fires
  65   // This function starts the actual throbbing.
  66   void StartDelayOver();
  67
  68   // Called when the shutdown-delay timer fires.
  69   // This function stops the actual throbbing.
  70   void StopDelayOver();
  71
  72   // Delay after work starts before starting throbber, in milliseconds.
  73   int start_delay_ms_;
  74
  75   // Delay after work stops before stopping, in milliseconds.
  76   int stop_delay_ms_;
  77
  78   base::OneShotTimer<SmoothedThrobber> start_timer_;
  79   base::OneShotTimer<SmoothedThrobber> stop_timer_;
  80
  81   DISALLOW_COPY_AND_ASSIGN(SmoothedThrobber);
  82 };
  83
  84 }  // namespace views
  85
  86 #endif  // UI_VIEWS_CONTROLS_THROBBER_H_