1 // Copyright 2013 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/message_center/views/bounded_label.h" 6 7 #include <limits> 8 9 #include "base/strings/string_util.h" 10 #include "base/strings/utf_string_conversions.h" 11 #include "ui/base/text/text_elider.h" 12 #include "ui/gfx/canvas.h" 13 #include "ui/views/controls/label.h" 14 15 namespace { 16 17 const size_t kPreferredLinesCacheSize = 10; 18 const size_t kPreferredSizeCacheSize = 10; 19 20 } // namespace 21 22 namespace message_center { 23 24 // InnerBoundedLabel /////////////////////////////////////////////////////////// 25 26 // InnerBoundedLabel is a views::Label subclass that does all of the work for 27 // BoundedLabel. It is kept private to prevent outside code from calling a 28 // number of views::Label methods like setFont() that break BoundedLabel's 29 // caching but can't be overridden. 30 // 31 // TODO(dharcourt): Move the line limiting functionality to views::Label to make 32 // this unnecessary. 33 34 class InnerBoundedLabel : public views::Label { 35 public: 36 InnerBoundedLabel(const BoundedLabel& owner); 37 virtual ~InnerBoundedLabel(); 38 39 void SetNativeTheme(const ui::NativeTheme* theme); 40 41 // Pass in a -1 width to use the preferred width, a -1 limit to skip limits. 42 int GetLinesForWidthAndLimit(int width, int limit); 43 gfx::Size GetSizeForWidthAndLines(int width, int lines); 44 std::vector<string16> GetWrappedText(int width, int lines); 45 46 protected: 47 // Overridden from views::Label. 48 virtual void OnBoundsChanged(const gfx::Rect& previous_bounds) OVERRIDE; 49 virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE; 50 51 private: 52 int GetTextFlags(); 53 54 void ClearCaches(); 55 int GetCachedLines(int width); 56 void SetCachedLines(int width, int lines); 57 gfx::Size GetCachedSize(const std::pair<int, int>& width_and_lines); 58 void SetCachedSize(std::pair<int, int> width_and_lines, gfx::Size size); 59 60 const BoundedLabel* owner_; // Weak reference. 61 string16 wrapped_text_; 62 int wrapped_text_width_; 63 int wrapped_text_lines_; 64 std::map<int, int> lines_cache_; 65 std::list<int> lines_widths_; // Most recently used in front. 66 std::map<std::pair<int, int>, gfx::Size> size_cache_; 67 std::list<std::pair<int, int> > size_widths_and_lines_; // Recent in front. 68 69 DISALLOW_COPY_AND_ASSIGN(InnerBoundedLabel); 70 }; 71 72 InnerBoundedLabel::InnerBoundedLabel(const BoundedLabel& owner) 73 : owner_(&owner), 74 wrapped_text_width_(0), 75 wrapped_text_lines_(0) { 76 SetMultiLine(true); 77 SetAllowCharacterBreak(true); 78 SetHorizontalAlignment(gfx::ALIGN_LEFT); 79 set_collapse_when_hidden(true); 80 } 81 82 InnerBoundedLabel::~InnerBoundedLabel() { 83 } 84 85 void InnerBoundedLabel::SetNativeTheme(const ui::NativeTheme* theme) { 86 ClearCaches(); 87 OnNativeThemeChanged(theme); 88 } 89 90 int InnerBoundedLabel::GetLinesForWidthAndLimit(int width, int limit) { 91 if (width == 0 || limit == 0) 92 return 0; 93 int lines = GetCachedLines(width); 94 if (lines == std::numeric_limits<int>::max()) { 95 int text_width = std::max(width - owner_->GetInsets().width(), 0); 96 lines = GetWrappedText(text_width, lines).size(); 97 SetCachedLines(width, lines); 98 } 99 return (limit < 0 || lines <= limit) ? lines : limit; 100 } 101 102 gfx::Size InnerBoundedLabel::GetSizeForWidthAndLines(int width, int lines) { 103 if (width == 0 || lines == 0) 104 return gfx::Size(); 105 std::pair<int, int> key(width, lines); 106 gfx::Size size = GetCachedSize(key); 107 if (size.height() == std::numeric_limits<int>::max()) { 108 gfx::Insets insets = owner_->GetInsets(); 109 int text_width = (width < 0) ? std::numeric_limits<int>::max() : 110 std::max(width - insets.width(), 0); 111 int text_height = std::numeric_limits<int>::max(); 112 std::vector<string16> wrapped = GetWrappedText(text_width, lines); 113 gfx::Canvas::SizeStringInt(JoinString(wrapped, '\n'), font(), 114 &text_width, &text_height, 115 owner_->GetLineHeight(), 116 GetTextFlags()); 117 size.set_width(text_width + insets.width()); 118 size.set_height(text_height + insets.height()); 119 SetCachedSize(key, size); 120 } 121 return size; 122 } 123 124 std::vector<string16> InnerBoundedLabel::GetWrappedText(int width, int lines) { 125 // Short circuit simple case. 126 if (width == 0 || lines == 0) 127 return std::vector<string16>(); 128 129 // Restrict line limit to ensure (lines + 1) * line_height <= INT_MAX and 130 // use it to calculate a reasonable text height. 131 int height = std::numeric_limits<int>::max(); 132 if (lines > 0) { 133 int line_height = std::max(font().GetHeight(), 2); // At least 2 pixels. 134 int max_lines = std::numeric_limits<int>::max() / line_height - 1; 135 lines = std::min(lines, max_lines); 136 height = (lines + 1) * line_height; 137 } 138 139 // Try to ensure that the width is no smaller than the width of the text's 140 // characters to avoid the http://crbug.com/237700 infinite loop. 141 // TODO(dharcourt): Remove when http://crbug.com/237700 is fixed. 142 width = std::max(width, 2 * font().GetStringWidth(UTF8ToUTF16("W"))); 143 144 // Wrap, using INT_MAX for -1 widths that indicate no wrapping. 145 std::vector<string16> wrapped; 146 ui::ElideRectangleText(text(), font(), 147 (width < 0) ? std::numeric_limits<int>::max() : width, 148 height, ui::WRAP_LONG_WORDS, &wrapped); 149 150 // Elide if necessary. 151 if (lines > 0 && wrapped.size() > static_cast<unsigned int>(lines)) { 152 // Add an ellipsis to the last line. If this ellipsis makes the last line 153 // too wide, that line will be further elided by the ui::ElideText below, 154 // so for example "ABC" could become "ABC..." and then "AB...". 155 string16 last = wrapped[lines - 1] + UTF8ToUTF16(ui::kEllipsis); 156 if (width > 0 && font().GetStringWidth(last) > width) 157 last = ui::ElideText(last, font(), width, ui::ELIDE_AT_END); 158 wrapped.resize(lines - 1); 159 wrapped.push_back(last); 160 } 161 162 return wrapped; 163 } 164 165 void InnerBoundedLabel::OnBoundsChanged(const gfx::Rect& previous_bounds) { 166 ClearCaches(); 167 views::Label::OnBoundsChanged(previous_bounds); 168 } 169 170 void InnerBoundedLabel::OnPaint(gfx::Canvas* canvas) { 171 views::Label::OnPaintBackground(canvas); 172 views::Label::OnPaintFocusBorder(canvas); 173 views::Label::OnPaintBorder(canvas); 174 int lines = owner_->GetLineLimit(); 175 int height = GetSizeForWidthAndLines(width(), lines).height(); 176 if (height > 0) { 177 gfx::Rect bounds(width(), height); 178 bounds.Inset(owner_->GetInsets()); 179 if (bounds.width() != wrapped_text_width_ || lines != wrapped_text_lines_) { 180 wrapped_text_ = JoinString(GetWrappedText(bounds.width(), lines), '\n'); 181 wrapped_text_width_ = bounds.width(); 182 wrapped_text_lines_ = lines; 183 } 184 bounds.set_x(GetMirroredXForRect(bounds)); 185 PaintText(canvas, wrapped_text_, bounds, GetTextFlags()); 186 } 187 } 188 189 int InnerBoundedLabel::GetTextFlags() { 190 int flags = gfx::Canvas::MULTI_LINE | gfx::Canvas::CHARACTER_BREAK; 191 192 // We can't use subpixel rendering if the background is non-opaque. 193 if (SkColorGetA(background_color()) != 0xFF) 194 flags |= gfx::Canvas::NO_SUBPIXEL_RENDERING; 195 196 if (directionality_mode() == 197 views::Label::AUTO_DETECT_DIRECTIONALITY) { 198 base::i18n::TextDirection direction = 199 base::i18n::GetFirstStrongCharacterDirection(text()); 200 if (direction == base::i18n::RIGHT_TO_LEFT) 201 flags |= gfx::Canvas::FORCE_RTL_DIRECTIONALITY; 202 else 203 flags |= gfx::Canvas::FORCE_LTR_DIRECTIONALITY; 204 } 205 206 return flags; 207 } 208 209 void InnerBoundedLabel::ClearCaches() { 210 wrapped_text_width_ = 0; 211 wrapped_text_lines_ = 0; 212 lines_cache_.clear(); 213 lines_widths_.clear(); 214 size_cache_.clear(); 215 size_widths_and_lines_.clear(); 216 } 217 218 int InnerBoundedLabel::GetCachedLines(int width) { 219 int lines = std::numeric_limits<int>::max(); 220 std::map<int, int>::const_iterator found; 221 if ((found = lines_cache_.find(width)) != lines_cache_.end()) { 222 lines = found->second; 223 lines_widths_.remove(width); 224 lines_widths_.push_front(width); 225 } 226 return lines; 227 } 228 229 void InnerBoundedLabel::SetCachedLines(int width, int lines) { 230 if (lines_cache_.size() >= kPreferredLinesCacheSize) { 231 lines_cache_.erase(lines_widths_.back()); 232 lines_widths_.pop_back(); 233 } 234 lines_cache_[width] = lines; 235 lines_widths_.push_front(width); 236 } 237 238 gfx::Size InnerBoundedLabel::GetCachedSize( 239 const std::pair<int, int>& width_and_lines) { 240 gfx::Size size(width_and_lines.first, std::numeric_limits<int>::max()); 241 std::map<std::pair<int, int>, gfx::Size>::const_iterator found; 242 if ((found = size_cache_.find(width_and_lines)) != size_cache_.end()) { 243 size = found->second; 244 size_widths_and_lines_.remove(width_and_lines); 245 size_widths_and_lines_.push_front(width_and_lines); 246 } 247 return size; 248 } 249 250 void InnerBoundedLabel::SetCachedSize(std::pair<int, int> width_and_lines, 251 gfx::Size size) { 252 if (size_cache_.size() >= kPreferredLinesCacheSize) { 253 size_cache_.erase(size_widths_and_lines_.back()); 254 size_widths_and_lines_.pop_back(); 255 } 256 size_cache_[width_and_lines] = size; 257 size_widths_and_lines_.push_front(width_and_lines); 258 } 259 260 // BoundedLabel /////////////////////////////////////////////////////////// 261 262 BoundedLabel::BoundedLabel(const string16& text, gfx::Font font) 263 : line_limit_(-1) { 264 label_.reset(new InnerBoundedLabel(*this)); 265 label_->SetFont(font); 266 label_->SetText(text); 267 } 268 269 BoundedLabel::BoundedLabel(const string16& text) 270 : line_limit_(-1) { 271 label_.reset(new InnerBoundedLabel(*this)); 272 label_->SetText(text); 273 } 274 275 BoundedLabel::~BoundedLabel() { 276 } 277 278 void BoundedLabel::SetColors(SkColor textColor, SkColor backgroundColor) { 279 label_->SetEnabledColor(textColor); 280 label_->SetBackgroundColor(backgroundColor); 281 } 282 283 void BoundedLabel::SetLineHeight(int height) { 284 label_->SetLineHeight(height); 285 } 286 287 void BoundedLabel::SetLineLimit(int lines) { 288 line_limit_ = std::max(lines, -1); 289 } 290 291 int BoundedLabel::GetLineHeight() const { 292 return label_->line_height(); 293 } 294 295 int BoundedLabel::GetLineLimit() const { 296 return line_limit_; 297 } 298 299 int BoundedLabel::GetLinesForWidthAndLimit(int width, int limit) { 300 return visible() ? label_->GetLinesForWidthAndLimit(width, limit) : 0; 301 } 302 303 gfx::Size BoundedLabel::GetSizeForWidthAndLines(int width, int lines) { 304 return visible() ? 305 label_->GetSizeForWidthAndLines(width, lines) : gfx::Size(); 306 } 307 308 int BoundedLabel::GetBaseline() const { 309 return label_->GetBaseline(); 310 } 311 312 gfx::Size BoundedLabel::GetPreferredSize() { 313 return visible() ? label_->GetSizeForWidthAndLines(-1, -1) : gfx::Size(); 314 } 315 316 int BoundedLabel::GetHeightForWidth(int width) { 317 return visible() ? 318 label_->GetSizeForWidthAndLines(width, line_limit_).height() : 0; 319 } 320 321 void BoundedLabel::Paint(gfx::Canvas* canvas) { 322 if (visible()) 323 label_->Paint(canvas); 324 } 325 326 bool BoundedLabel::HitTestRect(const gfx::Rect& rect) const { 327 return label_->HitTestRect(rect); 328 } 329 330 void BoundedLabel::GetAccessibleState(ui::AccessibleViewState* state) { 331 label_->GetAccessibleState(state); 332 } 333 334 void BoundedLabel::OnBoundsChanged(const gfx::Rect& previous_bounds) { 335 label_->SetBoundsRect(bounds()); 336 views::View::OnBoundsChanged(previous_bounds); 337 } 338 339 void BoundedLabel::OnNativeThemeChanged(const ui::NativeTheme* theme) { 340 label_->SetNativeTheme(theme); 341 } 342 343 string16 BoundedLabel::GetWrappedTextForTest(int width, int lines) { 344 return JoinString(label_->GetWrappedText(width, lines), '\n'); 345 } 346 347 } // namespace message_center 348