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/ui/views/location_bar/location_bar_view.h"
   8 #include "ui/gfx/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                         int builtin_padding,
  22                         views::View* view);
  23
  24   // The y position of the view inside its parent.
  25   int y;
  26
  27   // The height of the view.
  28   int height;
  29
  30   // True means that, if there is not enough available space in the location
  31   // bar, the view will reduce its width either to its minimal width or to zero
  32   // (making it invisible), whichever fits. If true, |max_fraction| must be 0.
  33   bool auto_collapse;
  34
  35   // Used for resizeable decorations, indicates the maximum fraction of the
  36   // location bar that can be taken by this decoration, 0 for non-resizable
  37   // decorations. If non-zero, |auto_collapse| must be false.
  38   double max_fraction;
  39
  40   // Padding to use if the decoration is the first element next to the edge.
  41   int edge_item_padding;
  42
  43   // Padding to use if the decoration follows another decoration.
  44   int item_padding;
  45
  46   // Padding built into the decoration and that should be removed, on
  47   // both sides, during layout.
  48   int builtin_padding;
  49
  50   views::View* view;
  51
  52   // The width computed by the layout process.
  53   double computed_width;
  54 };
  55
  56 LocationBarDecoration::LocationBarDecoration(int y,
  57                                              int height,
  58                                              bool auto_collapse,
  59                                              double max_fraction,
  60                                              int edge_item_padding,
  61                                              int item_padding,
  62                                              int builtin_padding,
  63                                              views::View* view)
  64     : y(y),
  65       height(height),
  66       auto_collapse(auto_collapse),
  67       max_fraction(max_fraction),
  68       edge_item_padding(edge_item_padding),
  69       item_padding(item_padding),
  70       builtin_padding(builtin_padding),
  71       view(view),
  72       computed_width(0) {
  73   DCHECK((max_fraction == 0.0) || (!auto_collapse && (max_fraction > 0.0)));
  74 }
  75
  76
  77 // LocationBarLayout ---------------------------------------------------------
  78
  79 LocationBarLayout::LocationBarLayout(Position position, int item_edit_padding)
  80     : position_(position),
  81       item_edit_padding_(item_edit_padding) {
  82 }
  83
  84
  85 LocationBarLayout::~LocationBarLayout() {
  86 }
  87
  88 void LocationBarLayout::AddDecoration(int y,
  89                                       int height,
  90                                       bool auto_collapse,
  91                                       double max_fraction,
  92                                       int edge_item_padding,
  93                                       int item_padding,
  94                                       int builtin_padding,
  95                                       views::View* view) {
  96   decorations_.push_back(new LocationBarDecoration(
  97       y, height, auto_collapse, max_fraction, edge_item_padding, item_padding,
  98       builtin_padding, view));
  99 }
 100
 101 void LocationBarLayout::AddDecoration(int y,
 102                                       int height,
 103                                       int builtin_padding,
 104                                       views::View* view) {
 105   decorations_.push_back(new LocationBarDecoration(
 106       y, height, false, 0, LocationBarView::GetItemPadding(),
 107       LocationBarView::GetItemPadding(), builtin_padding, view));
 108 }
 109
 110 void LocationBarLayout::LayoutPass1(int* entry_width) {
 111   bool first_item = true;
 112   for (Decorations::iterator i(decorations_.begin()); i != decorations_.end();
 113        ++i) {
 114     // Autocollapsing decorations are ignored in this pass.
 115     if (!(*i)->auto_collapse) {
 116       *entry_width -= -2 * (*i)->builtin_padding +
 117           (first_item ? (*i)->edge_item_padding : (*i)->item_padding);
 118     }
 119     first_item = false;
 120     // Resizing decorations are ignored in this pass.
 121     if (!(*i)->auto_collapse && ((*i)->max_fraction == 0.0)) {
 122       (*i)->computed_width = (*i)->view->GetPreferredSize().width();
 123       *entry_width -= (*i)->computed_width;
 124     }
 125   }
 126   *entry_width -= item_edit_padding_;
 127 }
 128
 129 void LocationBarLayout::LayoutPass2(int *entry_width) {
 130   for (Decorations::iterator i(decorations_.begin()); i != decorations_.end();
 131        ++i) {
 132     if ((*i)->max_fraction > 0.0) {
 133       int max_width = static_cast<int>(*entry_width * (*i)->max_fraction);
 134       (*i)->computed_width =
 135           std::min((*i)->view->GetPreferredSize().width(),
 136                    std::max((*i)->view->GetMinimumSize().width(), max_width));
 137       *entry_width -= (*i)->computed_width;
 138     }
 139   }
 140 }
 141
 142 void LocationBarLayout::LayoutPass3(gfx::Rect* bounds, int* available_width) {
 143   bool first_visible = true;
 144   for (Decorations::iterator i(decorations_.begin()); i != decorations_.end();
 145        ++i) {
 146     // Collapse decorations if needed.
 147     if ((*i)->auto_collapse) {
 148       int padding = -2 * (*i)->builtin_padding +
 149           (first_visible ? (*i)->edge_item_padding : (*i)->item_padding);
 150       // Try preferred size, if it fails try minimum size, if it fails collapse.
 151       (*i)->computed_width = (*i)->view->GetPreferredSize().width();
 152       if ((*i)->computed_width + padding > *available_width)
 153         (*i)->computed_width = (*i)->view->GetMinimumSize().width();
 154       if ((*i)->computed_width + padding > *available_width) {
 155         (*i)->computed_width = 0;
 156         (*i)->view->SetVisible(false);
 157       } else {
 158         (*i)->view->SetVisible(true);
 159         (*available_width) -= (*i)->computed_width + padding;
 160       }
 161     } else {
 162       (*i)->view->SetVisible(true);
 163     }
 164
 165     // Layout visible decorations.
 166     if (!(*i)->view->visible())
 167       continue;
 168     int padding = -(*i)->builtin_padding +
 169         (first_visible ? (*i)->edge_item_padding : (*i)->item_padding);
 170     first_visible = false;
 171     int x = (position_ == LEFT_EDGE) ? (bounds->x() + padding) :
 172         (bounds->right() - padding - (*i)->computed_width);
 173     (*i)->view->SetBounds(x, (*i)->y, (*i)->computed_width, (*i)->height);
 174     bounds->set_width(bounds->width() - padding - (*i)->computed_width +
 175         (*i)->builtin_padding);
 176     if (position_ == LEFT_EDGE) {
 177       bounds->set_x(
 178           bounds->x() + padding + (*i)->computed_width - (*i)->builtin_padding);
 179     }
 180   }
 181   bounds->set_width(bounds->width() - item_edit_padding_);
 182   if (position_ == LEFT_EDGE)
 183     bounds->set_x(bounds->x() + item_edit_padding_);
 184 }