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 #include "chrome/browser/chromeos/login/username_view.h"
6
7 #include "base/logging.h"
8 #include "base/utf_string_conversions.h"
9 #include "chrome/browser/chromeos/login/rounded_view.h"
10 #include "grit/generated_resources.h"
11 #include "third_party/skia/include/core/SkColorShader.h"
12 #include "third_party/skia/include/core/SkComposeShader.h"
13 #include "third_party/skia/include/effects/SkGradientShader.h"
14 #include "ui/base/l10n/l10n_util.h"
15 #include "ui/base/resource/resource_bundle.h"
16 #include "ui/gfx/canvas.h"
17 #include "ui/gfx/canvas_skia.h"
18 #include "ui/gfx/gtk_util.h"
19 #include "ui/gfx/rect.h"
20
21 namespace chromeos {
22
23 namespace {
24 // Username label background color.
25 const SkColor kLabelBackgoundColor = 0x55000000;
26 // Holds margin to height ratio.
27 const double kMarginRatio = 1.0 / 3.0;
28 // Holds the frame width for the small shaped username view.
29 const SkScalar kSmallShapeFrameWidth = SkIntToScalar(1);
30
31 // Class that sets up half rounded rectangle (only the bottom corners are
32 // rounded) as a clip region of the view.
33 // For more info see the file "chrome/browser/chromeos/login/rounded_view.h".
34 template<typename C>
35 class HalfRoundedView : public RoundedView<C> {
36 public:
HalfRoundedView(const std::wstring & text,bool use_small_shape)37 HalfRoundedView(const std::wstring &text, bool use_small_shape)
38 : RoundedView<C>(text, use_small_shape) {
39 }
40
41 protected:
42 // Overrides ViewFilter.
GetClipPath() const43 virtual SkPath GetClipPath() const {
44 if (!C::use_small_shape()) {
45 return RoundedView<C>::GetClipPath();
46 } else {
47 SkPath path;
48 gfx::Rect frame_bounds = this->bounds();
49 frame_bounds.Inset(kSmallShapeFrameWidth, kSmallShapeFrameWidth,
50 kSmallShapeFrameWidth, kSmallShapeFrameWidth);
51 path.addRect(SkIntToScalar(frame_bounds.x()),
52 SkIntToScalar(frame_bounds.y()),
53 SkIntToScalar(frame_bounds.x() + frame_bounds.width()),
54 SkIntToScalar(frame_bounds.y() + frame_bounds.height()));
55 return path;
56 }
57 }
58
DrawFrame(gfx::Canvas * canvas)59 virtual void DrawFrame(gfx::Canvas* canvas) {
60 // No frame is needed.
61 }
62
GetViewRect() const63 virtual SkRect GetViewRect() const {
64 SkRect view_rect;
65 // The rectangle will be intersected with the bounds, so the correct half
66 // of the round rectangle will be obtained.
67 view_rect.iset(this->x(),
68 this->y() - this->height(),
69 this->x() + this->width(),
70 this->y() + this->height());
71 return view_rect;
72 }
73 };
74
75 } // namespace
76
UsernameView(const std::wstring & username,bool use_small_shape)77 UsernameView::UsernameView(const std::wstring& username, bool use_small_shape)
78 : views::Label(username.empty()
79 ? UTF16ToWide(l10n_util::GetStringUTF16(IDS_GUEST)) : username),
80 use_small_shape_(use_small_shape),
81 is_guest_(username.empty()) {
82 }
83
OnPaint(gfx::Canvas * canvas)84 void UsernameView::OnPaint(gfx::Canvas* canvas) {
85 gfx::Rect bounds = GetContentsBounds();
86 if (text_image_ == NULL)
87 PaintUsername(bounds);
88 DCHECK(text_image_ != NULL);
89 DCHECK(bounds.size() ==
90 gfx::Size(text_image_->width(), text_image_->height()));
91 canvas->DrawBitmapInt(*text_image_, bounds.x(), bounds.y());
92 }
93
94 // static
CreateShapedUsernameView(const std::wstring & username,bool use_small_shape)95 UsernameView* UsernameView::CreateShapedUsernameView(
96 const std::wstring& username, bool use_small_shape) {
97 return new HalfRoundedView<UsernameView>(username, use_small_shape);
98 }
99
GetCursorForPoint(ui::EventType event_type,const gfx::Point & p)100 gfx::NativeCursor UsernameView::GetCursorForPoint(
101 ui::EventType event_type,
102 const gfx::Point& p) {
103 return use_small_shape_ ? gfx::GetCursor(GDK_HAND2) : NULL;
104 }
105
PaintUsername(const gfx::Rect & bounds)106 void UsernameView::PaintUsername(const gfx::Rect& bounds) {
107 margin_width_ = bounds.height() * kMarginRatio;
108 gfx::CanvasSkia canvas(bounds.width(), bounds.height(), false);
109 // Draw transparent background.
110 canvas.drawColor(0);
111
112 // Calculate needed space.
113 int flags = gfx::Canvas::TEXT_ALIGN_LEFT |
114 gfx::Canvas::TEXT_VALIGN_MIDDLE |
115 gfx::Canvas::NO_ELLIPSIS;
116 int text_height, text_width;
117 gfx::CanvasSkia::SizeStringInt(WideToUTF16Hack(GetText()), font(),
118 &text_width, &text_height,
119 flags);
120 text_width += margin_width_;
121
122 // Also leave the right margin.
123 bool use_fading_for_text = text_width + margin_width_ >= bounds.width();
124
125 // Only alpha channel counts.
126 SkColor gradient_colors[2];
127 gradient_colors[0] = 0xFFFFFFFF;
128 gradient_colors[1] = 0x00FFFFFF;
129
130 int gradient_start = use_fading_for_text ?
131 bounds.width() - bounds.height() - margin_width_ :
132 text_width;
133 int gradient_end = std::min(gradient_start + bounds.height(),
134 bounds.width() - margin_width_);
135
136 SkPoint gradient_borders[2];
137 gradient_borders[0].set(SkIntToScalar(gradient_start), SkIntToScalar(0));
138 gradient_borders[1].set(SkIntToScalar(gradient_end), SkIntToScalar(0));
139
140 SkShader* gradient_shader =
141 SkGradientShader::CreateLinear(gradient_borders, gradient_colors, NULL, 2,
142 SkShader::kClamp_TileMode, NULL);
143
144 if (!use_fading_for_text) {
145 // Draw the final background with the fading in the end.
146 SkShader* solid_shader = new SkColorShader(kLabelBackgoundColor);
147 SkXfermode* mode = SkXfermode::Create(SkXfermode::kSrcIn_Mode);
148 SkShader* composite_shader = new SkComposeShader(gradient_shader,
149 solid_shader, mode);
150 gradient_shader->unref();
151 solid_shader->unref();
152
153 SkPaint paint;
154 paint.setShader(composite_shader)->unref();
155 canvas.drawPaint(paint);
156 }
157
158 // Draw the text.
159 // Note, direct call of the DrawStringInt method produces the green dots
160 // along the text perimeter (when the label is place on the white background).
161 SkColor kInvisibleHaloColor = 0x00000000;
162 canvas.DrawStringWithHalo(WideToUTF16Hack(GetText()), font(), GetColor(),
163 kInvisibleHaloColor, bounds.x() + margin_width_,
164 bounds.y(), bounds.width() - 2 * margin_width_,
165 bounds.height(), flags);
166
167 text_image_.reset(new SkBitmap(canvas.ExtractBitmap()));
168
169 if (use_fading_for_text) {
170 // Fade out only the text in the end. Use regular background.
171 canvas.drawColor(kLabelBackgoundColor, SkXfermode::kSrc_Mode);
172 SkShader* image_shader = SkShader::CreateBitmapShader(
173 *text_image_,
174 SkShader::kRepeat_TileMode,
175 SkShader::kRepeat_TileMode);
176 SkXfermode* mode = SkXfermode::Create(SkXfermode::kSrcIn_Mode);
177 SkShader* composite_shader = new SkComposeShader(gradient_shader,
178 image_shader, mode);
179 gradient_shader->unref();
180 image_shader->unref();
181
182 SkPaint paint;
183 paint.setShader(composite_shader)->unref();
184 canvas.drawPaint(paint);
185 text_image_.reset(new SkBitmap(canvas.ExtractBitmap()));
186 }
187 }
188
OnLocaleChanged()189 void UsernameView::OnLocaleChanged() {
190 if (is_guest_) {
191 SetText(UTF16ToWide(l10n_util::GetStringUTF16(IDS_GUEST)));
192 }
193 // Repaint because the font may have changed.
194 text_image_.reset();
195 SchedulePaint();
196 }
197
198 } // namespace chromeos
199