ui/views/controls/button/image_button.cc

   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 #include "ui/views/controls/button/image_button.h"
   6
   7 #include "base/strings/utf_string_conversions.h"
   8 #include "ui/accessibility/ax_view_state.h"
   9 #include "ui/gfx/animation/throb_animation.h"
  10 #include "ui/gfx/canvas.h"
  11 #include "ui/gfx/image/image_skia_operations.h"
  12 #include "ui/gfx/scoped_canvas.h"
  13 #include "ui/views/painter.h"
  14 #include "ui/views/widget/widget.h"
  15
  16 namespace views {
  17
  18 static const int kDefaultWidth = 16;   // Default button width if no theme.
  19 static const int kDefaultHeight = 14;  // Default button height if no theme.
  20
  21 const char ImageButton::kViewClassName[] = "ImageButton";
  22
  23 ////////////////////////////////////////////////////////////////////////////////
  24 // ImageButton, public:
  25
  26 ImageButton::ImageButton(ButtonListener* listener)
  27     : CustomButton(listener),
  28       h_alignment_(ALIGN_LEFT),
  29       v_alignment_(ALIGN_TOP),
  30       preferred_size_(kDefaultWidth, kDefaultHeight),
  31       draw_image_mirrored_(false),
  32       focus_painter_(Painter::CreateDashedFocusPainter()) {
  33   // By default, we request that the gfx::Canvas passed to our View::OnPaint()
  34   // implementation is flipped horizontally so that the button's images are
  35   // mirrored when the UI directionality is right-to-left.
  36   EnableCanvasFlippingForRTLUI(true);
  37 }
  38
  39 ImageButton::~ImageButton() {
  40 }
  41
  42 const gfx::ImageSkia& ImageButton::GetImage(ButtonState state) const {
  43   return images_[state];
  44 }
  45
  46 void ImageButton::SetImage(ButtonState state, const gfx::ImageSkia* image) {
  47   images_[state] = image ? *image : gfx::ImageSkia();
  48   PreferredSizeChanged();
  49 }
  50
  51 void ImageButton::SetBackground(SkColor color,
  52                                 const gfx::ImageSkia* image,
  53                                 const gfx::ImageSkia* mask) {
  54   if (image == NULL || mask == NULL) {
  55     background_image_ = gfx::ImageSkia();
  56     return;
  57   }
  58
  59   background_image_ = gfx::ImageSkiaOperations::CreateButtonBackground(color,
  60      *image, *mask);
  61 }
  62
  63 void ImageButton::SetImageAlignment(HorizontalAlignment h_align,
  64                                     VerticalAlignment v_align) {
  65   h_alignment_ = h_align;
  66   v_alignment_ = v_align;
  67   SchedulePaint();
  68 }
  69
  70 void ImageButton::SetFocusPainter(scoped_ptr<Painter> focus_painter) {
  71   focus_painter_ = focus_painter.Pass();
  72 }
  73
  74 ////////////////////////////////////////////////////////////////////////////////
  75 // ImageButton, View overrides:
  76
  77 gfx::Size ImageButton::GetPreferredSize() const {
  78   gfx::Size size = preferred_size_;
  79   if (!images_[STATE_NORMAL].isNull()) {
  80     size = gfx::Size(images_[STATE_NORMAL].width(),
  81                      images_[STATE_NORMAL].height());
  82   }
  83
  84   gfx::Insets insets = GetInsets();
  85   size.Enlarge(insets.width(), insets.height());
  86   return size;
  87 }
  88
  89 const char* ImageButton::GetClassName() const {
  90   return kViewClassName;
  91 }
  92
  93 void ImageButton::OnPaint(gfx::Canvas* canvas) {
  94   // Call the base class first to paint any background/borders.
  95   View::OnPaint(canvas);
  96
  97   gfx::ImageSkia img = GetImageToPaint();
  98
  99   if (!img.isNull()) {
 100     gfx::ScopedCanvas scoped(canvas);
 101     if (draw_image_mirrored_) {
 102       canvas->Translate(gfx::Vector2d(width(), 0));
 103       canvas->Scale(-1, 1);
 104     }
 105
 106     gfx::Point position = ComputeImagePaintPosition(img);
 107     if (!background_image_.isNull())
 108       canvas->DrawImageInt(background_image_, position.x(), position.y());
 109
 110     canvas->DrawImageInt(img, position.x(), position.y());
 111   }
 112
 113   Painter::PaintFocusPainter(this, canvas, focus_painter());
 114 }
 115
 116 ////////////////////////////////////////////////////////////////////////////////
 117 // ImageButton, protected:
 118
 119 void ImageButton::OnFocus() {
 120   View::OnFocus();
 121   if (focus_painter_.get())
 122     SchedulePaint();
 123 }
 124
 125 void ImageButton::OnBlur() {
 126   View::OnBlur();
 127   if (focus_painter_.get())
 128     SchedulePaint();
 129 }
 130
 131 gfx::ImageSkia ImageButton::GetImageToPaint() {
 132   gfx::ImageSkia img;
 133
 134   if (!images_[STATE_HOVERED].isNull() && hover_animation_->is_animating()) {
 135     img = gfx::ImageSkiaOperations::CreateBlendedImage(images_[STATE_NORMAL],
 136         images_[STATE_HOVERED], hover_animation_->GetCurrentValue());
 137   } else {
 138     img = images_[state_];
 139   }
 140
 141   return !img.isNull() ? img : images_[STATE_NORMAL];
 142 }
 143
 144 ////////////////////////////////////////////////////////////////////////////////
 145 // ImageButton, private:
 146
 147 gfx::Point ImageButton::ComputeImagePaintPosition(const gfx::ImageSkia& image) {
 148   int x = 0, y = 0;
 149   gfx::Rect rect = GetContentsBounds();
 150
 151   HorizontalAlignment h_alignment = h_alignment_;
 152   if (draw_image_mirrored_) {
 153     if (h_alignment == ALIGN_RIGHT)
 154       h_alignment = ALIGN_LEFT;
 155     else if (h_alignment == ALIGN_LEFT)
 156       h_alignment = ALIGN_RIGHT;
 157   }
 158
 159   if (h_alignment == ALIGN_CENTER)
 160     x = (rect.width() - image.width()) / 2;
 161   else if (h_alignment == ALIGN_RIGHT)
 162     x = rect.width() - image.width();
 163
 164   if (v_alignment_ == ALIGN_MIDDLE)
 165     y = (rect.height() - image.height()) / 2;
 166   else if (v_alignment_ == ALIGN_BOTTOM)
 167     y = rect.height() - image.height();
 168
 169   x += rect.x();
 170   y += rect.y();
 171
 172   return gfx::Point(x, y);
 173 }
 174
 175 ////////////////////////////////////////////////////////////////////////////////
 176 // ToggleImageButton, public:
 177
 178 ToggleImageButton::ToggleImageButton(ButtonListener* listener)
 179     : ImageButton(listener),
 180       toggled_(false) {
 181 }
 182
 183 ToggleImageButton::~ToggleImageButton() {
 184 }
 185
 186 void ToggleImageButton::SetToggled(bool toggled) {
 187   if (toggled == toggled_)
 188     return;
 189
 190   for (int i = 0; i < STATE_COUNT; ++i) {
 191     gfx::ImageSkia temp = images_[i];
 192     images_[i] = alternate_images_[i];
 193     alternate_images_[i] = temp;
 194   }
 195   toggled_ = toggled;
 196   SchedulePaint();
 197
 198   NotifyAccessibilityEvent(ui::AX_EVENT_VALUE_CHANGED, true);
 199 }
 200
 201 void ToggleImageButton::SetToggledImage(ButtonState state,
 202                                         const gfx::ImageSkia* image) {
 203   if (toggled_) {
 204     images_[state] = image ? *image : gfx::ImageSkia();
 205     if (state_ == state)
 206       SchedulePaint();
 207   } else {
 208     alternate_images_[state] = image ? *image : gfx::ImageSkia();
 209   }
 210 }
 211
 212 void ToggleImageButton::SetToggledTooltipText(const base::string16& tooltip) {
 213   toggled_tooltip_text_ = tooltip;
 214 }
 215
 216 ////////////////////////////////////////////////////////////////////////////////
 217 // ToggleImageButton, ImageButton overrides:
 218
 219 const gfx::ImageSkia& ToggleImageButton::GetImage(ButtonState state) const {
 220   if (toggled_)
 221     return alternate_images_[state];
 222   return images_[state];
 223 }
 224
 225 void ToggleImageButton::SetImage(ButtonState state,
 226                                  const gfx::ImageSkia* image) {
 227   if (toggled_) {
 228     alternate_images_[state] = image ? *image : gfx::ImageSkia();
 229   } else {
 230     images_[state] = image ? *image : gfx::ImageSkia();
 231     if (state_ == state)
 232       SchedulePaint();
 233   }
 234   PreferredSizeChanged();
 235 }
 236
 237 ////////////////////////////////////////////////////////////////////////////////
 238 // ToggleImageButton, View overrides:
 239
 240 bool ToggleImageButton::GetTooltipText(const gfx::Point& p,
 241                                        base::string16* tooltip) const {
 242   if (!toggled_ || toggled_tooltip_text_.empty())
 243     return Button::GetTooltipText(p, tooltip);
 244
 245   *tooltip = toggled_tooltip_text_;
 246   return true;
 247 }
 248
 249 void ToggleImageButton::GetAccessibleState(ui::AXViewState* state) {
 250   ImageButton::GetAccessibleState(state);
 251   GetTooltipText(gfx::Point(), &state->name);
 252 }
 253
 254 }  // namespace views