ui/views/examples/multiline_example.cc

   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/views/examples/multiline_example.h"
   6
   7 #include "base/strings/utf_string_conversions.h"
   8 #include "ui/events/event.h"
   9 #include "ui/gfx/render_text.h"
  10 #include "ui/views/background.h"
  11 #include "ui/views/border.h"
  12 #include "ui/views/controls/button/checkbox.h"
  13 #include "ui/views/controls/label.h"
  14 #include "ui/views/controls/textfield/textfield.h"
  15 #include "ui/views/layout/grid_layout.h"
  16 #include "ui/views/view.h"
  17
  18 using base::ASCIIToUTF16;
  19
  20 namespace views {
  21 namespace examples {
  22
  23 namespace {
  24
  25 gfx::Range ClampRange(gfx::Range range, size_t max) {
  26   range.set_start(std::min(range.start(), max));
  27   range.set_end(std::min(range.end(), max));
  28   return range;
  29 }
  30
  31 // A Label with a clamped preferred width to demonstrate wrapping.
  32 class PreferredSizeLabel : public Label {
  33  public:
  34   PreferredSizeLabel() : Label() {}
  35   virtual ~PreferredSizeLabel() {}
  36
  37   // Label:
  38   virtual gfx::Size GetPreferredSize() const OVERRIDE {
  39     return gfx::Size(50, Label::GetPreferredSize().height());
  40   }
  41
  42  private:
  43   DISALLOW_COPY_AND_ASSIGN(PreferredSizeLabel);
  44 };
  45
  46 }  // namespace
  47
  48 // A simple View that hosts a RenderText object.
  49 class MultilineExample::RenderTextView : public View {
  50  public:
  51   RenderTextView() : render_text_(gfx::RenderText::CreateInstance()) {
  52     render_text_->SetHorizontalAlignment(gfx::ALIGN_CENTER);
  53     render_text_->SetColor(SK_ColorBLACK);
  54     render_text_->SetMultiline(true);
  55     SetBorder(Border::CreateSolidBorder(2, SK_ColorGRAY));
  56   }
  57
  58   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE {
  59     View::OnPaint(canvas);
  60     render_text_->Draw(canvas);
  61   }
  62
  63   virtual gfx::Size GetPreferredSize() const OVERRIDE {
  64     // Turn off multiline mode to get the single-line text size, which is the
  65     // preferred size for this view.
  66     render_text_->SetMultiline(false);
  67     gfx::Size size(render_text_->GetContentWidth(),
  68                    render_text_->GetStringSize().height());
  69     size.Enlarge(GetInsets().width(), GetInsets().height());
  70     render_text_->SetMultiline(true);
  71     return size;
  72   }
  73
  74   virtual int GetHeightForWidth(int w) const OVERRIDE {
  75     // TODO(ckocagil): Why does this happen?
  76     if (w == 0)
  77       return View::GetHeightForWidth(w);
  78     const gfx::Rect old_rect = render_text_->display_rect();
  79     gfx::Rect rect = old_rect;
  80     rect.set_width(w - GetInsets().width());
  81     render_text_->SetDisplayRect(rect);
  82     int height = render_text_->GetStringSize().height() + GetInsets().height();
  83     render_text_->SetDisplayRect(old_rect);
  84     return height;
  85   }
  86
  87   void SetText(const base::string16& new_contents) {
  88     // Color and style the text inside |test_range| to test colors and styles.
  89     const size_t range_max = new_contents.length();
  90     gfx::Range color_range = ClampRange(gfx::Range(1, 21), range_max);
  91     gfx::Range bold_range = ClampRange(gfx::Range(4, 10), range_max);
  92     gfx::Range italic_range = ClampRange(gfx::Range(7, 13), range_max);
  93
  94     render_text_->SetText(new_contents);
  95     render_text_->SetColor(SK_ColorBLACK);
  96     render_text_->ApplyColor(0xFFFF0000, color_range);
  97     render_text_->SetStyle(gfx::DIAGONAL_STRIKE, false);
  98     render_text_->ApplyStyle(gfx::DIAGONAL_STRIKE, true, color_range);
  99     render_text_->SetStyle(gfx::UNDERLINE, false);
 100     render_text_->ApplyStyle(gfx::UNDERLINE, true, color_range);
 101     render_text_->ApplyStyle(gfx::BOLD, true, bold_range);
 102     render_text_->ApplyStyle(gfx::ITALIC, true, italic_range);
 103     InvalidateLayout();
 104   }
 105
 106  private:
 107   virtual void OnBoundsChanged(const gfx::Rect& previous_bounds) OVERRIDE {
 108     gfx::Rect bounds = GetLocalBounds();
 109     bounds.Inset(GetInsets());
 110     render_text_->SetDisplayRect(bounds);
 111   }
 112
 113   scoped_ptr<gfx::RenderText> render_text_;
 114
 115   DISALLOW_COPY_AND_ASSIGN(RenderTextView);
 116 };
 117
 118 MultilineExample::MultilineExample()
 119     : ExampleBase("Multiline RenderText"),
 120       render_text_view_(NULL),
 121       label_(NULL),
 122       textfield_(NULL),
 123       label_checkbox_(NULL) {
 124 }
 125
 126 MultilineExample::~MultilineExample() {
 127 }
 128
 129 void MultilineExample::CreateExampleView(View* container) {
 130   const base::string16 kTestString = base::WideToUTF16(L"qwerty"
 131       L"\x627\x644\x631\x626\x64A\x633\x64A\x629"
 132       L"asdfgh");
 133
 134   render_text_view_ = new RenderTextView();
 135   render_text_view_->SetText(kTestString);
 136
 137   label_ = new PreferredSizeLabel();
 138   label_->SetText(kTestString);
 139   label_->SetMultiLine(true);
 140   label_->SetBorder(Border::CreateSolidBorder(2, SK_ColorCYAN));
 141
 142   label_checkbox_ = new Checkbox(ASCIIToUTF16("views::Label:"));
 143   label_checkbox_->SetChecked(true);
 144   label_checkbox_->set_listener(this);
 145   label_checkbox_->set_request_focus_on_press(false);
 146
 147   textfield_ = new Textfield();
 148   textfield_->set_controller(this);
 149   textfield_->SetText(kTestString);
 150
 151   GridLayout* layout = new GridLayout(container);
 152   container->SetLayoutManager(layout);
 153
 154   ColumnSet* column_set = layout->AddColumnSet(0);
 155   column_set->AddColumn(GridLayout::LEADING, GridLayout::CENTER,
 156       0.0f, GridLayout::USE_PREF, 0, 0);
 157   column_set->AddColumn(GridLayout::FILL, GridLayout::FILL,
 158       1.0f, GridLayout::FIXED, 0, 0);
 159
 160   layout->StartRow(0, 0);
 161   layout->AddView(new Label(ASCIIToUTF16("gfx::RenderText:")));
 162   layout->AddView(render_text_view_);
 163
 164   layout->StartRow(0, 0);
 165   layout->AddView(label_checkbox_);
 166   layout->AddView(label_);
 167
 168   layout->StartRow(0, 0);
 169   layout->AddView(new Label(ASCIIToUTF16("Sample Text:")));
 170   layout->AddView(textfield_);
 171 }
 172
 173 void MultilineExample::ContentsChanged(Textfield* sender,
 174                                        const base::string16& new_contents) {
 175   render_text_view_->SetText(new_contents);
 176   if (label_checkbox_->checked())
 177     label_->SetText(new_contents);
 178   container()->Layout();
 179   container()->SchedulePaint();
 180 }
 181
 182 void MultilineExample::ButtonPressed(Button* sender, const ui::Event& event) {
 183   DCHECK_EQ(sender, label_checkbox_);
 184   label_->SetText(label_checkbox_->checked() ? textfield_->text() :
 185                                                base::string16());
 186   container()->Layout();
 187   container()->SchedulePaint();
 188 }
 189
 190 }  // namespace examples
 191 }  // namespace views