ui/gfx/animation/multi_animation.h

   1 // Copyright (c) 2011 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_GFX_ANIMATION_MULTI_ANIMATION_H_
   6 #define UI_GFX_ANIMATION_MULTI_ANIMATION_H_
   7
   8 #include <vector>
   9
  10 #include "ui/gfx/animation/animation.h"
  11 #include "ui/gfx/animation/tween.h"
  12
  13 namespace gfx {
  14
  15 // MultiAnimation is an animation that consists of a number of sub animations.
  16 // To create a MultiAnimation pass in the parts, invoke Start() and the delegate
  17 // is notified as the animation progresses. By default MultiAnimation runs until
  18 // Stop is invoked, see |set_continuous()| for details.
  19 class GFX_EXPORT MultiAnimation : public Animation {
  20  public:
  21   // Defines part of the animation. Each part consists of the following:
  22   //
  23   // time_ms: the time of the part.
  24   // start_time_ms: the amount of time to offset this part by when calculating
  25   // the percented completed.
  26   // end_time_ms: the end time used to calculate the percentange completed.
  27   //
  28   // In most cases |start_time_ms| = 0 and |end_time_ms| = |time_ms|. But you
  29   // can adjust the start/end for different effects. For example, to run a part
  30   // for 200ms with a % between .25 and .75 use the following three values: 200,
  31   // 100, 400.
  32   struct Part {
  33     Part() : time_ms(0), start_time_ms(0), end_time_ms(0), type(Tween::ZERO) {}
  34     Part(int time_ms, Tween::Type type)
  35         : time_ms(time_ms),
  36           start_time_ms(0),
  37           end_time_ms(time_ms),
  38           type(type) {}
  39
  40     int time_ms;
  41     int start_time_ms;
  42     int end_time_ms;
  43     Tween::Type type;
  44   };
  45
  46   typedef std::vector<Part> Parts;
  47
  48   MultiAnimation(const Parts& parts, base::TimeDelta timer_interval);
  49   ~MultiAnimation() override;
  50
  51   // Default interval.
  52   static base::TimeDelta GetDefaultTimerInterval();
  53
  54   // Sets whether the animation continues after it reaches the end. If true, the
  55   // animation runs until explicitly stopped. The default is true.
  56   void set_continuous(bool continuous) { continuous_ = continuous; }
  57
  58   // Returns the current value. The current value for a MultiAnimation is
  59   // determined from the tween type of the current part.
  60   double GetCurrentValue() const override;
  61
  62   // Returns the index of the current part.
  63   size_t current_part_index() const { return current_part_index_; }
  64
  65  protected:
  66   // Animation overrides.
  67   void Step(base::TimeTicks time_now) override;
  68   void SetStartTime(base::TimeTicks start_time) override;
  69
  70  private:
  71   // Returns the part containing the specified time. |time_ms| is reset to be
  72   // relative to the part containing the time and |part_index| the index of the
  73   // part.
  74   const Part& GetPart(int* time_ms, size_t* part_index);
  75
  76   // The parts that make up the animation.
  77   const Parts parts_;
  78
  79   // Total time of all the parts.
  80   const int cycle_time_ms_;
  81
  82   // Current value for the animation.
  83   double current_value_;
  84
  85   // Index of the current part.
  86   size_t current_part_index_;
  87
  88   // See description above setter.
  89   bool continuous_;
  90
  91   DISALLOW_COPY_AND_ASSIGN(MultiAnimation);
  92 };
  93
  94 }  // namespace gfx
  95
  96 #endif  // UI_GFX_ANIMATION_MULTI_ANIMATION_H_