ui/views/bubble/bubble_border.h

   1 // Copyright (c) 2012 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_BUBBLE_BUBBLE_BORDER_H_
   6 #define UI_VIEWS_BUBBLE_BUBBLE_BORDER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/compiler_specific.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "ui/gfx/image/image_skia.h"
  12 #include "ui/views/background.h"
  13 #include "ui/views/border.h"
  14
  15 namespace gfx {
  16 class Rect;
  17 }
  18
  19 namespace views {
  20 class Painter;
  21
  22 namespace internal {
  23
  24 // A helper that combines each border image-set painter with arrows and metrics.
  25 struct BorderImages {
  26   BorderImages(const int border_image_ids[],
  27                const int arrow_image_ids[],
  28                int border_interior_thickness,
  29                int arrow_interior_thickness,
  30                int corner_radius);
  31   virtual ~BorderImages();
  32
  33   scoped_ptr<Painter> border_painter;
  34   gfx::ImageSkia left_arrow;
  35   gfx::ImageSkia top_arrow;
  36   gfx::ImageSkia right_arrow;
  37   gfx::ImageSkia bottom_arrow;
  38
  39   // The thickness of border and arrow images and their interior areas.
  40   // Thickness is the width of left/right and the height of top/bottom images.
  41   // The interior is measured without including stroke or shadow pixels.
  42   int border_thickness;
  43   int border_interior_thickness;
  44   int arrow_thickness;
  45   int arrow_interior_thickness;
  46   // The corner radius of the bubble's rounded-rect interior area.
  47   int corner_radius;
  48 };
  49
  50 }  // namespace internal
  51
  52 // Renders a border, with optional arrow, and a custom dropshadow.
  53 // This can be used to produce floating "bubble" objects with rounded corners.
  54 class VIEWS_EXPORT BubbleBorder : public Border {
  55  public:
  56   // Possible locations for the (optional) arrow.
  57   // 0 bit specifies left or right.
  58   // 1 bit specifies top or bottom.
  59   // 2 bit specifies horizontal or vertical.
  60   // 3 bit specifies whether the arrow at the center of its residing edge.
  61   enum ArrowMask {
  62     RIGHT    = 0x01,
  63     BOTTOM   = 0x02,
  64     VERTICAL = 0x04,
  65     CENTER   = 0x08,
  66   };
  67
  68   enum Arrow {
  69     TOP_LEFT      = 0,
  70     TOP_RIGHT     = RIGHT,
  71     BOTTOM_LEFT   = BOTTOM,
  72     BOTTOM_RIGHT  = BOTTOM | RIGHT,
  73     LEFT_TOP      = VERTICAL,
  74     RIGHT_TOP     = VERTICAL | RIGHT,
  75     LEFT_BOTTOM   = VERTICAL | BOTTOM,
  76     RIGHT_BOTTOM  = VERTICAL | BOTTOM | RIGHT,
  77     TOP_CENTER    = CENTER,
  78     BOTTOM_CENTER = CENTER | BOTTOM,
  79     LEFT_CENTER   = CENTER | VERTICAL,
  80     RIGHT_CENTER  = CENTER | VERTICAL | RIGHT,
  81     NONE  = 16,  // No arrow. Positioned under the supplied rect.
  82     FLOAT = 17,  // No arrow. Centered over the supplied rect.
  83   };
  84
  85   enum Shadow {
  86     NO_SHADOW = 0,
  87     NO_SHADOW_OPAQUE_BORDER,
  88     BIG_SHADOW,
  89     SMALL_SHADOW,
  90     SHADOW_COUNT,
  91   };
  92
  93   // The position of the bubble in relation to the anchor.
  94   enum BubbleAlignment {
  95     // The tip of the arrow points to the middle of the anchor.
  96     ALIGN_ARROW_TO_MID_ANCHOR,
  97     // The edge nearest to the arrow is lined up with the edge of the anchor.
  98     ALIGN_EDGE_TO_ANCHOR_EDGE,
  99   };
 100
 101   // The way the arrow should be painted.
 102   enum ArrowPaintType {
 103     // Fully render the arrow.
 104     PAINT_NORMAL,
 105     // Leave space for the arrow, but do not paint it.
 106     PAINT_TRANSPARENT,
 107     // Neither paint nor leave space for the arrow.
 108     PAINT_NONE,
 109   };
 110
 111   BubbleBorder(Arrow arrow, Shadow shadow, SkColor color);
 112   virtual ~BubbleBorder();
 113
 114   // Returns the radius of the corner of the border.
 115   // TODO(xiyuan): Get rid of this since it's part of BorderImages now?
 116   static int GetCornerRadius() {
 117     // We can't safely calculate a border radius by comparing the sizes of the
 118     // side and corner images, because either may have been extended in various
 119     // directions in order to do more subtle dropshadow fading or other effects.
 120     // So we hardcode the most accurate value.
 121     return 4;
 122   }
 123
 124   static bool has_arrow(Arrow a) { return a < NONE; }
 125
 126   static bool is_arrow_on_left(Arrow a) {
 127     return has_arrow(a) && (a == LEFT_CENTER || !(a & (RIGHT | CENTER)));
 128   }
 129
 130   static bool is_arrow_on_top(Arrow a) {
 131     return has_arrow(a) && (a == TOP_CENTER || !(a & (BOTTOM | CENTER)));
 132   }
 133
 134   static bool is_arrow_on_horizontal(Arrow a) {
 135     return a >= NONE ? false : !(a & VERTICAL);
 136   }
 137
 138   static bool is_arrow_at_center(Arrow a) {
 139     return has_arrow(a) && !!(a & CENTER);
 140   }
 141
 142   static Arrow horizontal_mirror(Arrow a) {
 143     return (a == TOP_CENTER || a == BOTTOM_CENTER || a >= NONE) ?
 144         a : static_cast<Arrow>(a ^ RIGHT);
 145   }
 146
 147   static Arrow vertical_mirror(Arrow a) {
 148     return (a == LEFT_CENTER || a == RIGHT_CENTER || a >= NONE) ?
 149         a : static_cast<Arrow>(a ^ BOTTOM);
 150   }
 151
 152   // Get or set the arrow type.
 153   void set_arrow(Arrow arrow) { arrow_ = arrow; }
 154   Arrow arrow() const { return arrow_; }
 155
 156   // Get or set the bubble alignment.
 157   void set_alignment(BubbleAlignment alignment) { alignment_ = alignment; }
 158   BubbleAlignment alignment() const { return alignment_; }
 159
 160   // Get the shadow type.
 161   Shadow shadow() const { return shadow_; }
 162
 163   // Get or set the background color for the bubble and arrow body.
 164   void set_background_color(SkColor color) { background_color_ = color; }
 165   SkColor background_color() const { return background_color_; }
 166
 167   // If true, the background color should be determined by the host's
 168   // NativeTheme.
 169   void set_use_theme_background_color(bool use_theme_background_color) {
 170     use_theme_background_color_ = use_theme_background_color;
 171   }
 172   bool use_theme_background_color() { return use_theme_background_color_; }
 173
 174   // Sets a desired pixel distance between the arrow tip and the outside edge of
 175   // the neighboring border image. For example:    |----offset----|
 176   // '(' represents shadow around the '{' edge:    ((({           ^   })))
 177   // The arrow will still anchor to the same location but the bubble will shift
 178   // location to place the arrow |offset| pixels from the perpendicular edge.
 179   void set_arrow_offset(int offset) { arrow_offset_ = offset; }
 180
 181   // Sets the way the arrow is actually painted.  Default is PAINT_NORMAL.
 182   void set_paint_arrow(ArrowPaintType value) { arrow_paint_type_ = value; }
 183
 184   // Get the desired widget bounds (in screen coordinates) given the anchor rect
 185   // and bubble content size; calculated from shadow and arrow image dimensions.
 186   virtual gfx::Rect GetBounds(const gfx::Rect& anchor_rect,
 187                               const gfx::Size& contents_size) const;
 188
 189   // Get the border exterior thickness, including stroke and shadow, in pixels.
 190   int GetBorderThickness() const;
 191
 192   // Returns the corner radius of the current image set.
 193   int GetBorderCornerRadius() const;
 194
 195   // Gets the arrow offset to use.
 196   int GetArrowOffset(const gfx::Size& border_size) const;
 197
 198   // Overridden from Border:
 199   virtual void Paint(const View& view, gfx::Canvas* canvas) OVERRIDE;
 200   virtual gfx::Insets GetInsets() const OVERRIDE;
 201   virtual gfx::Size GetMinimumSize() const OVERRIDE;
 202
 203  private:
 204   FRIEND_TEST_ALL_PREFIXES(BubbleBorderTest, GetSizeForContentsSizeTest);
 205   FRIEND_TEST_ALL_PREFIXES(BubbleBorderTest, GetBoundsOriginTest);
 206
 207   // The border and arrow stroke size used in image assets, in pixels.
 208   static const int kStroke;
 209
 210   gfx::Size GetSizeForContentsSize(const gfx::Size& contents_size) const;
 211   gfx::ImageSkia* GetArrowImage() const;
 212   gfx::Rect GetArrowRect(const gfx::Rect& bounds) const;
 213   void DrawArrow(gfx::Canvas* canvas, const gfx::Rect& arrow_bounds) const;
 214
 215   internal::BorderImages* GetImagesForTest() const;
 216
 217   Arrow arrow_;
 218   int arrow_offset_;
 219   ArrowPaintType arrow_paint_type_;
 220   BubbleAlignment alignment_;
 221   Shadow shadow_;
 222   internal::BorderImages* images_;
 223   SkColor background_color_;
 224   bool use_theme_background_color_;
 225
 226   DISALLOW_COPY_AND_ASSIGN(BubbleBorder);
 227 };
 228
 229 // A Background that clips itself to the specified BubbleBorder and uses
 230 // the background color of the BubbleBorder.
 231 class VIEWS_EXPORT BubbleBackground : public Background {
 232  public:
 233   explicit BubbleBackground(BubbleBorder* border) : border_(border) {}
 234
 235   // Overridden from Background:
 236   virtual void Paint(gfx::Canvas* canvas, View* view) const OVERRIDE;
 237
 238  private:
 239   BubbleBorder* border_;
 240
 241   DISALLOW_COPY_AND_ASSIGN(BubbleBackground);
 242 };
 243
 244 }  // namespace views
 245
 246 #endif  // UI_VIEWS_BUBBLE_BUBBLE_BORDER_H_