chrome/browser/ui/views/location_bar/location_bar_layout.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 "chrome/browser/ui/views/location_bar/location_bar_layout.h"
   6
   7 #include "chrome/browser/themes/theme_properties.h"
   8 #include "ui/gfx/geometry/rect.h"
   9 #include "ui/views/view.h"
  10
  11
  12 // Description of a decoration to be added inside the location bar, either to
  13 // the left or to the right.
  14 struct LocationBarDecoration {
  15   LocationBarDecoration(int y,
  16                         int height,
  17                         bool auto_collapse,
  18                         double max_fraction,
  19                         int edge_item_padding,
  20                         int item_padding,
  21                         views::View* view);
  22
  23   // The y position of the view inside its parent.
  24   int y;
  25
  26   // The height of the view.
  27   int height;
  28
  29   // True means that, if there is not enough available space in the location
  30   // bar, the view will reduce its width either to its minimal width or to zero
  31   // (making it invisible), whichever fits. If true, |max_fraction| must be 0.
  32   bool auto_collapse;
  33
  34   // Used for resizeable decorations, indicates the maximum fraction of the
  35   // location bar that can be taken by this decoration, 0 for non-resizable
  36   // decorations. If non-zero, |auto_collapse| must be false.
  37   double max_fraction;
  38
  39   // Padding to use if the decoration is the first element next to the edge.
  40   int edge_item_padding;
  41
  42   // Padding to use if the decoration follows another decoration.
  43   int item_padding;
  44
  45   views::View* view;
  46
  47   // The width computed by the layout process.
  48   double computed_width;
  49 };
  50
  51 LocationBarDecoration::LocationBarDecoration(int y,
  52                                              int height,
  53                                              bool auto_collapse,
  54                                              double max_fraction,
  55                                              int edge_item_padding,
  56                                              int item_padding,
  57                                              views::View* view)
  58     : y(y),
  59       height(height),
  60       auto_collapse(auto_collapse),
  61       max_fraction(max_fraction),
  62       edge_item_padding(edge_item_padding),
  63       item_padding(item_padding),
  64       view(view),
  65       computed_width(0) {
  66   DCHECK((max_fraction == 0.0) || (!auto_collapse && (max_fraction > 0.0)));
  67 }
  68
  69
  70 // LocationBarLayout ---------------------------------------------------------
  71
  72 LocationBarLayout::LocationBarLayout(Position position,
  73                                      int item_padding,
  74                                      int item_edit_padding)
  75     : position_(position),
  76       item_padding_(item_padding),
  77       item_edit_padding_(item_edit_padding) {}
  78
  79 LocationBarLayout::~LocationBarLayout() {
  80 }
  81
  82 void LocationBarLayout::AddDecoration(int y,
  83                                       int height,
  84                                       bool auto_collapse,
  85                                       double max_fraction,
  86                                       int edge_item_padding,
  87                                       int item_padding,
  88                                       views::View* view) {
  89   decorations_.push_back(new LocationBarDecoration(
  90       y, height, auto_collapse, max_fraction, edge_item_padding, item_padding,
  91       view));
  92 }
  93
  94 void LocationBarLayout::AddDecoration(int y,
  95                                       int height,
  96                                       views::View* view) {
  97   decorations_.push_back(new LocationBarDecoration(
  98       y, height, false, 0, item_padding_, item_padding_, view));
  99 }
 100
 101 void LocationBarLayout::LayoutPass1(int* entry_width) {
 102   bool first_item = true;
 103   for (Decorations::iterator i(decorations_.begin()); i != decorations_.end();
 104        ++i) {
 105     // Autocollapsing decorations are ignored in this pass.
 106     if (!(*i)->auto_collapse) {
 107       *entry_width -=
 108           (first_item ? (*i)->edge_item_padding : (*i)->item_padding);
 109     }
 110     first_item = false;
 111     // Resizing decorations are ignored in this pass.
 112     if (!(*i)->auto_collapse && ((*i)->max_fraction == 0.0)) {
 113       (*i)->computed_width = (*i)->view->GetPreferredSize().width();
 114       *entry_width -= (*i)->computed_width;
 115     }
 116   }
 117   *entry_width -= item_edit_padding_;
 118 }
 119
 120 void LocationBarLayout::LayoutPass2(int *entry_width) {
 121   for (Decorations::iterator i(decorations_.begin()); i != decorations_.end();
 122        ++i) {
 123     if ((*i)->max_fraction > 0.0) {
 124       int max_width = static_cast<int>(*entry_width * (*i)->max_fraction);
 125       (*i)->computed_width =
 126           std::min((*i)->view->GetPreferredSize().width(),
 127                    std::max((*i)->view->GetMinimumSize().width(), max_width));
 128       *entry_width -= (*i)->computed_width;
 129     }
 130   }
 131 }
 132
 133 void LocationBarLayout::LayoutPass3(gfx::Rect* bounds, int* available_width) {
 134   bool first_visible = true;
 135   for (Decorations::iterator i(decorations_.begin()); i != decorations_.end();
 136        ++i) {
 137     // Collapse decorations if needed.
 138     if ((*i)->auto_collapse) {
 139       int padding =
 140           (first_visible ? (*i)->edge_item_padding : (*i)->item_padding);
 141       // Try preferred size, if it fails try minimum size, if it fails collapse.
 142       (*i)->computed_width = (*i)->view->GetPreferredSize().width();
 143       if ((*i)->computed_width + padding > *available_width)
 144         (*i)->computed_width = (*i)->view->GetMinimumSize().width();
 145       if ((*i)->computed_width + padding > *available_width) {
 146         (*i)->computed_width = 0;
 147         (*i)->view->SetVisible(false);
 148       } else {
 149         (*i)->view->SetVisible(true);
 150         (*available_width) -= (*i)->computed_width + padding;
 151       }
 152     } else {
 153       (*i)->view->SetVisible(true);
 154     }
 155
 156     // Layout visible decorations.
 157     if (!(*i)->view->visible())
 158       continue;
 159     int padding =
 160         (first_visible ? (*i)->edge_item_padding : (*i)->item_padding);
 161     first_visible = false;
 162     int x = (position_ == LEFT_EDGE) ? (bounds->x() + padding) :
 163         (bounds->right() - padding - (*i)->computed_width);
 164     (*i)->view->SetBounds(x, (*i)->y, (*i)->computed_width, (*i)->height);
 165     bounds->set_width(bounds->width() - padding - (*i)->computed_width);
 166     if (position_ == LEFT_EDGE)
 167       bounds->set_x(bounds->x() + padding + (*i)->computed_width);
 168   }
 169   bounds->set_width(bounds->width() - item_edit_padding_);
 170   if (position_ == LEFT_EDGE)
 171     bounds->set_x(bounds->x() + item_edit_padding_);
 172 }