ui/touch_selection/touch_selection_controller.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 UI_TOUCH_SELECTION_TOUCH_SELECTION_CONTROLLER_H_
   6 #define UI_TOUCH_SELECTION_TOUCH_SELECTION_CONTROLLER_H_
   7
   8 #include "ui/base/touch/selection_bound.h"
   9 #include "ui/gfx/geometry/point_f.h"
  10 #include "ui/gfx/geometry/rect_f.h"
  11 #include "ui/touch_selection/selection_event_type.h"
  12 #include "ui/touch_selection/touch_handle.h"
  13 #include "ui/touch_selection/touch_handle_orientation.h"
  14 #include "ui/touch_selection/ui_touch_selection_export.h"
  15
  16 namespace ui {
  17 class MotionEvent;
  18
  19 // Interface through which |TouchSelectionController| issues selection-related
  20 // commands, notifications and requests.
  21 class UI_TOUCH_SELECTION_EXPORT TouchSelectionControllerClient {
  22  public:
  23   virtual ~TouchSelectionControllerClient() {}
  24
  25   virtual bool SupportsAnimation() const = 0;
  26   virtual void SetNeedsAnimate() = 0;
  27   virtual void MoveCaret(const gfx::PointF& position) = 0;
  28   virtual void MoveRangeSelectionExtent(const gfx::PointF& extent) = 0;
  29   virtual void SelectBetweenCoordinates(const gfx::PointF& base,
  30                                         const gfx::PointF& extent) = 0;
  31   virtual void OnSelectionEvent(SelectionEventType event,
  32                                 const gfx::PointF& position) = 0;
  33   virtual scoped_ptr<TouchHandleDrawable> CreateDrawable() = 0;
  34 };
  35
  36 // Controller for manipulating text selection via touch input.
  37 class UI_TOUCH_SELECTION_EXPORT TouchSelectionController
  38     : public TouchHandleClient {
  39  public:
  40   TouchSelectionController(TouchSelectionControllerClient* client,
  41                            base::TimeDelta tap_timeout,
  42                            float tap_slop,
  43                            bool show_on_tap_for_empty_editable);
  44   ~TouchSelectionController() override;
  45
  46   // To be called when the selection bounds have changed.
  47   // Note that such updates will trigger handle updates only if preceded
  48   // by an appropriate call to allow automatic showing.
  49   void OnSelectionBoundsChanged(const SelectionBound& start,
  50                                 const SelectionBound& end);
  51
  52   // Allows touch-dragging of the handle.
  53   // Returns true iff the event was consumed, in which case the caller should
  54   // cease further handling of the event.
  55   bool WillHandleTouchEvent(const MotionEvent& event);
  56
  57   // To be called before forwarding a tap event. This allows automatically
  58   // showing the insertion handle from subsequent bounds changes.
  59   void OnTapEvent();
  60
  61   // To be called before forwarding a longpress event. This allows automatically
  62   // showing the selection or insertion handles from subsequent bounds changes.
  63   void OnLongPressEvent();
  64
  65   // Allow showing the selection handles from the most recent selection bounds
  66   // update (if valid), or a future valid bounds update.
  67   void AllowShowingFromCurrentSelection();
  68
  69   // Hide the handles and suppress bounds updates until the next explicit
  70   // showing allowance.
  71   void HideAndDisallowShowingAutomatically();
  72
  73   // Override the handle visibility according to |hidden|.
  74   void SetTemporarilyHidden(bool hidden);
  75
  76   // To be called when the editability of the focused region changes.
  77   void OnSelectionEditable(bool editable);
  78
  79   // To be called when the contents of the focused region changes.
  80   void OnSelectionEmpty(bool empty);
  81
  82   // Ticks an active animation, as requested to the client by |SetNeedsAnimate|.
  83   // Returns true if an animation is active and requires further ticking.
  84   bool Animate(base::TimeTicks animate_time);
  85
  86  private:
  87   enum InputEventType { TAP, LONG_PRESS, INPUT_EVENT_TYPE_NONE };
  88
  89   // TouchHandleClient implementation.
  90   void OnHandleDragBegin(const TouchHandle& handle) override;
  91   void OnHandleDragUpdate(const TouchHandle& handle,
  92                           const gfx::PointF& new_position) override;
  93   void OnHandleDragEnd(const TouchHandle& handle) override;
  94   void OnHandleTapped(const TouchHandle& handle) override;
  95   void SetNeedsAnimate() override;
  96   scoped_ptr<TouchHandleDrawable> CreateDrawable() override;
  97   base::TimeDelta GetTapTimeout() const override;
  98   float GetTapSlop() const override;
  99
 100   void ShowInsertionHandleAutomatically();
 101   void ShowSelectionHandlesAutomatically();
 102
 103   void OnInsertionChanged();
 104   void OnSelectionChanged();
 105
 106   void ActivateInsertion();
 107   void DeactivateInsertion();
 108   void ActivateSelection();
 109   void DeactivateSelection();
 110   void ResetCachedValuesIfInactive();
 111
 112   const gfx::PointF& GetStartPosition() const;
 113   const gfx::PointF& GetEndPosition() const;
 114   gfx::Vector2dF GetStartLineOffset() const;
 115   gfx::Vector2dF GetEndLineOffset() const;
 116   bool GetStartVisible() const;
 117   bool GetEndVisible() const;
 118   TouchHandle::AnimationStyle GetAnimationStyle(bool was_active) const;
 119
 120   void LogSelectionEnd();
 121
 122   TouchSelectionControllerClient* const client_;
 123   const base::TimeDelta tap_timeout_;
 124   const float tap_slop_;
 125
 126   // Controls whether an insertion handle is shown on a tap for an empty
 127   // editable text.
 128   bool show_on_tap_for_empty_editable_;
 129
 130   InputEventType response_pending_input_event_;
 131
 132   SelectionBound start_;
 133   SelectionBound end_;
 134   TouchHandleOrientation start_orientation_;
 135   TouchHandleOrientation end_orientation_;
 136
 137   scoped_ptr<TouchHandle> insertion_handle_;
 138   bool is_insertion_active_;
 139   bool activate_insertion_automatically_;
 140
 141   scoped_ptr<TouchHandle> start_selection_handle_;
 142   scoped_ptr<TouchHandle> end_selection_handle_;
 143   bool is_selection_active_;
 144   bool activate_selection_automatically_;
 145
 146   bool selection_empty_;
 147   bool selection_editable_;
 148
 149   bool temporarily_hidden_;
 150
 151   base::TimeTicks selection_start_time_;
 152   // Whether a selection handle was dragged during the current 'selection
 153   // session' - i.e. since the current selection has been activated.
 154   bool selection_handle_dragged_;
 155
 156   DISALLOW_COPY_AND_ASSIGN(TouchSelectionController);
 157 };
 158
 159 }  // namespace ui
 160
 161 #endif  // UI_TOUCH_SELECTION_TOUCH_SELECTION_CONTROLLER_H_