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) = 0;
  32   virtual scoped_ptr<TouchHandleDrawable> CreateDrawable() = 0;
  33 };
  34
  35 // Controller for manipulating text selection via touch input.
  36 class UI_TOUCH_SELECTION_EXPORT TouchSelectionController
  37     : public TouchHandleClient {
  38  public:
  39   TouchSelectionController(TouchSelectionControllerClient* client,
  40                            base::TimeDelta tap_timeout,
  41                            float tap_slop,
  42                            bool show_on_tap_for_empty_editable);
  43   ~TouchSelectionController() override;
  44
  45   // To be called when the selection bounds have changed.
  46   // Note that such updates will trigger handle updates only if preceded
  47   // by an appropriate call to allow automatic showing.
  48   void OnSelectionBoundsChanged(const SelectionBound& start,
  49                                 const SelectionBound& end);
  50
  51   // Allows touch-dragging of the handle.
  52   // Returns true iff the event was consumed, in which case the caller should
  53   // cease further handling of the event.
  54   bool WillHandleTouchEvent(const MotionEvent& event);
  55
  56   // To be called before forwarding a tap event. This allows automatically
  57   // showing the insertion handle from subsequent bounds changes.
  58   void OnTapEvent();
  59
  60   // To be called before forwarding a longpress event. This allows automatically
  61   // showing the selection or insertion handles from subsequent bounds changes.
  62   void OnLongPressEvent();
  63
  64   // Allow showing the selection handles from the most recent selection bounds
  65   // update (if valid), or a future valid bounds update.
  66   void AllowShowingFromCurrentSelection();
  67
  68   // Hide the handles and suppress bounds updates until the next explicit
  69   // showing allowance.
  70   void HideAndDisallowShowingAutomatically();
  71
  72   // Override the handle visibility according to |hidden|.
  73   void SetTemporarilyHidden(bool hidden);
  74
  75   // To be called when the editability of the focused region changes.
  76   void OnSelectionEditable(bool editable);
  77
  78   // To be called when the contents of the focused region changes.
  79   void OnSelectionEmpty(bool empty);
  80
  81   // Ticks an active animation, as requested to the client by |SetNeedsAnimate|.
  82   // Returns true if an animation is active and requires further ticking.
  83   bool Animate(base::TimeTicks animate_time);
  84
  85   // Returns the rect between the two active selection bounds. If just one of
  86   // the bounds is visible, the rect is simply the (one-dimensional) rect of
  87   // that bound. If no selection is active, an empty rect will be returned.
  88   gfx::RectF GetRectBetweenBounds() const;
  89
  90   // Returns the visible rect of specified touch handle. For an active insertion
  91   // these values will be identical.
  92   gfx::RectF GetStartHandleRect() const;
  93   gfx::RectF GetEndHandleRect() const;
  94
  95   // Returns the focal point of the start and end bounds, as defined by
  96   // their bottom coordinate.
  97   const gfx::PointF& GetStartPosition() const;
  98   const gfx::PointF& GetEndPosition() const;
  99
 100  private:
 101   enum InputEventType { TAP, LONG_PRESS, INPUT_EVENT_TYPE_NONE };
 102
 103   // TouchHandleClient implementation.
 104   void OnHandleDragBegin(const TouchHandle& handle) override;
 105   void OnHandleDragUpdate(const TouchHandle& handle,
 106                           const gfx::PointF& new_position) override;
 107   void OnHandleDragEnd(const TouchHandle& handle) override;
 108   void OnHandleTapped(const TouchHandle& handle) override;
 109   void SetNeedsAnimate() override;
 110   scoped_ptr<TouchHandleDrawable> CreateDrawable() override;
 111   base::TimeDelta GetTapTimeout() const override;
 112   float GetTapSlop() const override;
 113
 114   void ShowInsertionHandleAutomatically();
 115   void ShowSelectionHandlesAutomatically();
 116
 117   void OnInsertionChanged();
 118   void OnSelectionChanged();
 119
 120   void ActivateInsertion();
 121   void DeactivateInsertion();
 122   void ActivateSelection();
 123   void DeactivateSelection();
 124   void ResetCachedValuesIfInactive();
 125
 126   gfx::Vector2dF GetStartLineOffset() const;
 127   gfx::Vector2dF GetEndLineOffset() const;
 128   bool GetStartVisible() const;
 129   bool GetEndVisible() const;
 130   TouchHandle::AnimationStyle GetAnimationStyle(bool was_active) const;
 131
 132   void LogSelectionEnd();
 133
 134   TouchSelectionControllerClient* const client_;
 135   const base::TimeDelta tap_timeout_;
 136   const float tap_slop_;
 137
 138   // Controls whether an insertion handle is shown on a tap for an empty
 139   // editable text.
 140   bool show_on_tap_for_empty_editable_;
 141
 142   InputEventType response_pending_input_event_;
 143
 144   SelectionBound start_;
 145   SelectionBound end_;
 146   TouchHandleOrientation start_orientation_;
 147   TouchHandleOrientation end_orientation_;
 148
 149   scoped_ptr<TouchHandle> insertion_handle_;
 150   bool is_insertion_active_;
 151   bool activate_insertion_automatically_;
 152
 153   scoped_ptr<TouchHandle> start_selection_handle_;
 154   scoped_ptr<TouchHandle> end_selection_handle_;
 155   bool is_selection_active_;
 156   bool activate_selection_automatically_;
 157
 158   bool selection_empty_;
 159   bool selection_editable_;
 160
 161   bool temporarily_hidden_;
 162
 163   base::TimeTicks selection_start_time_;
 164   // Whether a selection handle was dragged during the current 'selection
 165   // session' - i.e. since the current selection has been activated.
 166   bool selection_handle_dragged_;
 167
 168   DISALLOW_COPY_AND_ASSIGN(TouchSelectionController);
 169 };
 170
 171 }  // namespace ui
 172
 173 #endif  // UI_TOUCH_SELECTION_TOUCH_SELECTION_CONTROLLER_H_