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   enum ActiveStatus {
  40     INACTIVE,
  41     INSERTION_ACTIVE,
  42     SELECTION_ACTIVE,
  43   };
  44
  45   TouchSelectionController(TouchSelectionControllerClient* client,
  46                            base::TimeDelta tap_timeout,
  47                            float tap_slop,
  48                            bool show_on_tap_for_empty_editable);
  49   ~TouchSelectionController() override;
  50
  51   // To be called when the selection bounds have changed.
  52   // Note that such updates will trigger handle updates only if preceded
  53   // by an appropriate call to allow automatic showing.
  54   void OnSelectionBoundsChanged(const SelectionBound& start,
  55                                 const SelectionBound& end);
  56
  57   // Allows touch-dragging of the handle.
  58   // Returns true iff the event was consumed, in which case the caller should
  59   // cease further handling of the event.
  60   bool WillHandleTouchEvent(const MotionEvent& event);
  61
  62   // To be called before forwarding a tap event. This allows automatically
  63   // showing the insertion handle from subsequent bounds changes.
  64   bool WillHandleTapEvent(const gfx::PointF& location);
  65
  66   // To be called before forwarding a longpress event. This allows automatically
  67   // showing the selection or insertion handles from subsequent bounds changes.
  68   bool WillHandleLongPressEvent(const gfx::PointF& location);
  69
  70   // Allow showing the selection handles from the most recent selection bounds
  71   // update (if valid), or a future valid bounds update.
  72   void AllowShowingFromCurrentSelection();
  73
  74   // Hide the handles and suppress bounds updates until the next explicit
  75   // showing allowance.
  76   void HideAndDisallowShowingAutomatically();
  77
  78   // Override the handle visibility according to |hidden|.
  79   void SetTemporarilyHidden(bool hidden);
  80
  81   // To be called when the editability of the focused region changes.
  82   void OnSelectionEditable(bool editable);
  83
  84   // To be called when the contents of the focused region changes.
  85   void OnSelectionEmpty(bool empty);
  86
  87   // Ticks an active animation, as requested to the client by |SetNeedsAnimate|.
  88   // Returns true if an animation is active and requires further ticking.
  89   bool Animate(base::TimeTicks animate_time);
  90
  91   // Returns the rect between the two active selection bounds. If just one of
  92   // the bounds is visible, the rect is simply the (one-dimensional) rect of
  93   // that bound. If no selection is active, an empty rect will be returned.
  94   gfx::RectF GetRectBetweenBounds() const;
  95
  96   // Returns the visible rect of specified touch handle. For an active insertion
  97   // these values will be identical.
  98   gfx::RectF GetStartHandleRect() const;
  99   gfx::RectF GetEndHandleRect() const;
 100
 101   // Returns the focal point of the start and end bounds, as defined by
 102   // their bottom coordinate.
 103   const gfx::PointF& GetStartPosition() const;
 104   const gfx::PointF& GetEndPosition() const;
 105
 106   const SelectionBound& start() const { return start_; }
 107   const SelectionBound& end() const { return end_; }
 108
 109   ActiveStatus active_status() const { return active_status_; }
 110
 111  private:
 112   enum InputEventType { TAP, LONG_PRESS, INPUT_EVENT_TYPE_NONE };
 113
 114   // TouchHandleClient implementation.
 115   void OnHandleDragBegin(const TouchHandle& handle) override;
 116   void OnHandleDragUpdate(const TouchHandle& handle,
 117                           const gfx::PointF& new_position) override;
 118   void OnHandleDragEnd(const TouchHandle& handle) override;
 119   void OnHandleTapped(const TouchHandle& handle) override;
 120   void SetNeedsAnimate() override;
 121   scoped_ptr<TouchHandleDrawable> CreateDrawable() override;
 122   base::TimeDelta GetTapTimeout() const override;
 123   float GetTapSlop() const override;
 124
 125   void ShowInsertionHandleAutomatically();
 126   void ShowSelectionHandlesAutomatically();
 127   bool WillHandleTapOrLongPress(const gfx::PointF& location);
 128
 129   void OnInsertionChanged();
 130   void OnSelectionChanged();
 131
 132   void ActivateInsertion();
 133   void DeactivateInsertion();
 134   void ActivateSelection();
 135   void DeactivateSelection();
 136   void ForceNextUpdateIfInactive();
 137
 138   gfx::Vector2dF GetStartLineOffset() const;
 139   gfx::Vector2dF GetEndLineOffset() const;
 140   bool GetStartVisible() const;
 141   bool GetEndVisible() const;
 142   TouchHandle::AnimationStyle GetAnimationStyle(bool was_active) const;
 143
 144   void LogSelectionEnd();
 145
 146   TouchSelectionControllerClient* const client_;
 147   const base::TimeDelta tap_timeout_;
 148   const float tap_slop_;
 149
 150   // Whether to force an update on the next selection event even if the
 151   // cached selection matches the new selection.
 152   bool force_next_update_;
 153
 154   // Controls whether an insertion handle is shown on a tap for an empty
 155   // editable text.
 156   bool show_on_tap_for_empty_editable_;
 157
 158   InputEventType response_pending_input_event_;
 159
 160   SelectionBound start_;
 161   SelectionBound end_;
 162   TouchHandleOrientation start_orientation_;
 163   TouchHandleOrientation end_orientation_;
 164
 165   ActiveStatus active_status_;
 166
 167   scoped_ptr<TouchHandle> insertion_handle_;
 168   bool activate_insertion_automatically_;
 169
 170   scoped_ptr<TouchHandle> start_selection_handle_;
 171   scoped_ptr<TouchHandle> end_selection_handle_;
 172   bool activate_selection_automatically_;
 173
 174   bool selection_empty_;
 175   bool selection_editable_;
 176
 177   bool temporarily_hidden_;
 178
 179   base::TimeTicks selection_start_time_;
 180   // Whether a selection handle was dragged during the current 'selection
 181   // session' - i.e. since the current selection has been activated.
 182   bool selection_handle_dragged_;
 183
 184   DISALLOW_COPY_AND_ASSIGN(TouchSelectionController);
 185 };
 186
 187 }  // namespace ui
 188
 189 #endif  // UI_TOUCH_SELECTION_TOUCH_SELECTION_CONTROLLER_H_