ui/views/controls/single_split_view.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_VIEWS_CONTROLS_SINGLE_SPLIT_VIEW_H_
   6 #define UI_VIEWS_CONTROLS_SINGLE_SPLIT_VIEW_H_
   7
   8 #include "base/gtest_prod_util.h"
   9 #include "ui/views/view.h"
  10
  11 namespace views {
  12
  13 class SingleSplitViewListener;
  14
  15 // SingleSplitView lays out two views next to each other, either horizontally
  16 // or vertically. A splitter exists between the two views that the user can
  17 // drag around to resize the views.
  18 // SingleSplitViewListener's SplitHandleMoved notification helps to monitor user
  19 // initiated layout changes.
  20 class VIEWS_EXPORT SingleSplitView : public View {
  21  public:
  22   enum Orientation {
  23     HORIZONTAL_SPLIT,
  24     VERTICAL_SPLIT
  25   };
  26
  27   static const char kViewClassName[];
  28
  29   SingleSplitView(View* leading,
  30                   View* trailing,
  31                   Orientation orientation,
  32                   SingleSplitViewListener* listener);
  33
  34   void Layout() override;
  35   const char* GetClassName() const override;
  36
  37   void GetAccessibleState(ui::AXViewState* state) override;
  38
  39   // SingleSplitView's preferred size is the sum of the preferred widths
  40   // and the max of the heights.
  41   gfx::Size GetPreferredSize() const override;
  42
  43   // Overriden to return a resize cursor when over the divider.
  44   gfx::NativeCursor GetCursor(const ui::MouseEvent& event) override;
  45
  46   Orientation orientation() const {
  47     return is_horizontal_ ? HORIZONTAL_SPLIT : VERTICAL_SPLIT;
  48   }
  49
  50   void set_orientation(Orientation orientation) {
  51     is_horizontal_ = orientation == HORIZONTAL_SPLIT;
  52   }
  53
  54   void set_divider_offset(int divider_offset) {
  55     divider_offset_ = divider_offset;
  56   }
  57   int divider_offset() const { return divider_offset_; }
  58
  59   int GetDividerSize() const;
  60
  61   void set_resize_disabled(bool resize_disabled) {
  62     resize_disabled_ = resize_disabled;
  63   }
  64   bool is_resize_disabled() const { return resize_disabled_; }
  65
  66   // Sets whether the leading component is resized when the split views size
  67   // changes. The default is true. A value of false results in the trailing
  68   // component resizing on a bounds change.
  69   void set_resize_leading_on_bounds_change(bool resize) {
  70     resize_leading_on_bounds_change_ = resize;
  71   }
  72
  73   // Calculates ideal leading and trailing view bounds according to the given
  74   // split view |bounds|, current divider offset and children visiblity.
  75   // Does not change children view bounds.
  76   void CalculateChildrenBounds(const gfx::Rect& bounds,
  77                                gfx::Rect* leading_bounds,
  78                                gfx::Rect* trailing_bounds) const;
  79
  80   void SetAccessibleName(const base::string16& name);
  81
  82  protected:
  83   // View overrides.
  84   bool OnMousePressed(const ui::MouseEvent& event) override;
  85   bool OnMouseDragged(const ui::MouseEvent& event) override;
  86   void OnMouseCaptureLost() override;
  87   void OnBoundsChanged(const gfx::Rect& previous_bounds) override;
  88
  89  private:
  90   // This test calls OnMouse* functions.
  91   FRIEND_TEST_ALL_PREFIXES(SingleSplitViewTest, MouseDrag);
  92
  93   // Returns true if |x| or |y| is over the divider.
  94   bool IsPointInDivider(const gfx::Point& p);
  95
  96   // Calculates the new |divider_offset| based on the changes of split view
  97   // bounds.
  98   int CalculateDividerOffset(int divider_offset,
  99                              const gfx::Rect& previous_bounds,
 100                              const gfx::Rect& new_bounds) const;
 101
 102   // Returns divider offset within primary axis size range for given split
 103   // view |bounds|.
 104   int NormalizeDividerOffset(int divider_offset, const gfx::Rect& bounds) const;
 105
 106   // Returns width in case of horizontal split and height otherwise.
 107   int GetPrimaryAxisSize() const {
 108     return GetPrimaryAxisSize(width(), height());
 109   }
 110
 111   int GetPrimaryAxisSize(int h, int v) const {
 112     return is_horizontal_ ? h : v;
 113   }
 114
 115   // Used to track drag info.
 116   struct DragInfo {
 117     // The initial coordinate of the mouse when the user started the drag.
 118     int initial_mouse_offset;
 119     // The initial position of the divider when the user started the drag.
 120     int initial_divider_offset;
 121   };
 122
 123   DragInfo drag_info_;
 124
 125   // Orientation of the split view.
 126   bool is_horizontal_;
 127
 128   // Position of the divider.
 129   int divider_offset_;
 130
 131   bool resize_leading_on_bounds_change_;
 132
 133   // Whether resizing is disabled.
 134   bool resize_disabled_;
 135
 136   // Listener to notify about user initiated handle movements. Not owned.
 137   SingleSplitViewListener* listener_;
 138
 139   // The accessible name of this view.
 140   base::string16 accessible_name_;
 141
 142   DISALLOW_COPY_AND_ASSIGN(SingleSplitView);
 143 };
 144
 145 }  // namespace views
 146
 147 #endif  // UI_VIEWS_CONTROLS_SINGLE_SPLIT_VIEW_H_