ui/views/controls/link.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/link.h"
   6
   7 #include "build/build_config.h"
   8
   9 #include "base/logging.h"
  10 #include "base/strings/utf_string_conversions.h"
  11 #include "ui/accessibility/ax_view_state.h"
  12 #include "ui/base/cursor/cursor.h"
  13 #include "ui/events/event.h"
  14 #include "ui/events/keycodes/keyboard_codes.h"
  15 #include "ui/gfx/canvas.h"
  16 #include "ui/gfx/color_utils.h"
  17 #include "ui/gfx/font_list.h"
  18 #include "ui/views/controls/link_listener.h"
  19 #include "ui/views/native_cursor.h"
  20
  21 namespace views {
  22
  23 const char Link::kViewClassName[] = "Link";
  24
  25 Link::Link() : Label(base::string16()) {
  26   Init();
  27 }
  28
  29 Link::Link(const base::string16& title) : Label(title) {
  30   Init();
  31 }
  32
  33 Link::~Link() {
  34 }
  35
  36 SkColor Link::GetDefaultEnabledColor() {
  37 #if defined(OS_WIN)
  38   return color_utils::GetSysSkColor(COLOR_HOTLIGHT);
  39 #else
  40   return SkColorSetRGB(0, 51, 153);
  41 #endif
  42 }
  43
  44 const char* Link::GetClassName() const {
  45   return kViewClassName;
  46 }
  47
  48 gfx::NativeCursor Link::GetCursor(const ui::MouseEvent& event) {
  49   if (!enabled())
  50     return gfx::kNullCursor;
  51   return GetNativeHandCursor();
  52 }
  53
  54 bool Link::CanProcessEventsWithinSubtree() const {
  55   // Links need to be able to accept events (e.g., clicking) even though
  56   // in general Labels do not.
  57   return View::CanProcessEventsWithinSubtree();
  58 }
  59
  60 bool Link::OnMousePressed(const ui::MouseEvent& event) {
  61   if (!enabled() ||
  62       (!event.IsLeftMouseButton() && !event.IsMiddleMouseButton()))
  63     return false;
  64   SetPressed(true);
  65   return true;
  66 }
  67
  68 bool Link::OnMouseDragged(const ui::MouseEvent& event) {
  69   SetPressed(enabled() &&
  70              (event.IsLeftMouseButton() || event.IsMiddleMouseButton()) &&
  71              HitTestPoint(event.location()));
  72   return true;
  73 }
  74
  75 void Link::OnMouseReleased(const ui::MouseEvent& event) {
  76   // Change the highlight first just in case this instance is deleted
  77   // while calling the controller
  78   OnMouseCaptureLost();
  79   if (enabled() &&
  80       (event.IsLeftMouseButton() || event.IsMiddleMouseButton()) &&
  81       HitTestPoint(event.location())) {
  82     // Focus the link on click.
  83     RequestFocus();
  84
  85     if (listener_)
  86       listener_->LinkClicked(this, event.flags());
  87   }
  88 }
  89
  90 void Link::OnMouseCaptureLost() {
  91   SetPressed(false);
  92 }
  93
  94 bool Link::OnKeyPressed(const ui::KeyEvent& event) {
  95   bool activate = ((event.key_code() == ui::VKEY_SPACE) ||
  96                    (event.key_code() == ui::VKEY_RETURN));
  97   if (!activate)
  98     return false;
  99
 100   SetPressed(false);
 101
 102   // Focus the link on key pressed.
 103   RequestFocus();
 104
 105   if (listener_)
 106     listener_->LinkClicked(this, event.flags());
 107
 108   return true;
 109 }
 110
 111 void Link::OnGestureEvent(ui::GestureEvent* event) {
 112   if (!enabled())
 113     return;
 114
 115   if (event->type() == ui::ET_GESTURE_TAP_DOWN) {
 116     SetPressed(true);
 117   } else if (event->type() == ui::ET_GESTURE_TAP) {
 118     RequestFocus();
 119     if (listener_)
 120       listener_->LinkClicked(this, event->flags());
 121   } else {
 122     SetPressed(false);
 123     return;
 124   }
 125   event->SetHandled();
 126 }
 127
 128 bool Link::SkipDefaultKeyEventProcessing(const ui::KeyEvent& event) {
 129   // Make sure we don't process space or enter as accelerators.
 130   return (event.key_code() == ui::VKEY_SPACE) ||
 131       (event.key_code() == ui::VKEY_RETURN);
 132 }
 133
 134 void Link::GetAccessibleState(ui::AXViewState* state) {
 135   Label::GetAccessibleState(state);
 136   state->role = ui::AX_ROLE_LINK;
 137 }
 138
 139 void Link::OnEnabledChanged() {
 140   RecalculateFont();
 141   View::OnEnabledChanged();
 142 }
 143
 144 void Link::OnFocus() {
 145   Label::OnFocus();
 146   // We render differently focused.
 147   SchedulePaint();
 148 }
 149
 150 void Link::OnBlur() {
 151   Label::OnBlur();
 152   // We render differently focused.
 153   SchedulePaint();
 154 }
 155
 156 void Link::SetFontList(const gfx::FontList& font_list) {
 157   Label::SetFontList(font_list);
 158   RecalculateFont();
 159 }
 160
 161 void Link::SetText(const base::string16& text) {
 162   Label::SetText(text);
 163   // Disable focusability for empty links.  Otherwise Label::GetInsets() will
 164   // give them an unconditional 1-px. inset on every side to allow for a focus
 165   // border, when in this case we probably wanted zero width.
 166   SetFocusable(!text.empty());
 167 }
 168
 169 void Link::SetEnabledColor(SkColor color) {
 170   requested_enabled_color_ = color;
 171   if (!pressed_)
 172     Label::SetEnabledColor(requested_enabled_color_);
 173 }
 174
 175 void Link::SetPressedColor(SkColor color) {
 176   requested_pressed_color_ = color;
 177   if (pressed_)
 178     Label::SetEnabledColor(requested_pressed_color_);
 179 }
 180
 181 void Link::SetUnderline(bool underline) {
 182   if (underline_ == underline)
 183     return;
 184   underline_ = underline;
 185   RecalculateFont();
 186 }
 187
 188 void Link::Init() {
 189   listener_ = NULL;
 190   pressed_ = false;
 191   underline_ = true;
 192   SetEnabledColor(GetDefaultEnabledColor());
 193 #if defined(OS_WIN)
 194   SetDisabledColor(color_utils::GetSysSkColor(COLOR_WINDOWTEXT));
 195   SetPressedColor(SkColorSetRGB(200, 0, 0));
 196 #else
 197   // TODO(beng): source from theme provider.
 198   SetDisabledColor(SK_ColorBLACK);
 199   SetPressedColor(SK_ColorRED);
 200 #endif
 201   RecalculateFont();
 202
 203   // Label::Init() calls SetText(), but if that's being called from Label(), our
 204   // SetText() override will not be reached (because the constructed class is
 205   // only a Label at the moment, not yet a Link).  So so the set_focusable()
 206   // call explicitly here.
 207   SetFocusable(!text().empty());
 208 }
 209
 210 void Link::SetPressed(bool pressed) {
 211   if (pressed_ != pressed) {
 212     pressed_ = pressed;
 213     Label::SetEnabledColor(pressed_ ?
 214         requested_pressed_color_ : requested_enabled_color_);
 215     RecalculateFont();
 216     SchedulePaint();
 217   }
 218 }
 219
 220 void Link::RecalculateFont() {
 221   // Underline the link iff it is enabled and |underline_| is true.
 222   const int style = font_list().GetFontStyle();
 223   const int intended_style = (enabled() && underline_) ?
 224       (style | gfx::Font::UNDERLINE) : (style & ~gfx::Font::UNDERLINE);
 225   if (style != intended_style)
 226     Label::SetFontList(font_list().DeriveWithStyle(intended_style));
 227 }
 228
 229 }  // namespace views