ash/wm/window_resizer.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 "ash/wm/window_resizer.h"
   6
   7 #include "ash/screen_ash.h"
   8 #include "ash/shell.h"
   9 #include "ash/wm/property_util.h"
  10 #include "ash/wm/window_util.h"
  11 #include "ui/aura/client/aura_constants.h"
  12 #include "ui/aura/root_window.h"
  13 #include "ui/aura/window.h"
  14 #include "ui/aura/window_delegate.h"
  15 #include "ui/base/hit_test.h"
  16 #include "ui/base/ui_base_types.h"
  17 #include "ui/compositor/scoped_layer_animation_settings.h"
  18 #include "ui/gfx/display.h"
  19 #include "ui/gfx/screen.h"
  20
  21 namespace ash {
  22
  23 namespace {
  24
  25 int GetPositionChangeDirectionForWindowComponent(int window_component) {
  26   int pos_change_direction = WindowResizer::kBoundsChangeDirection_None;
  27   switch (window_component) {
  28     case HTTOPLEFT:
  29     case HTBOTTOMRIGHT:
  30     case HTGROWBOX:
  31     case HTCAPTION:
  32       pos_change_direction |=
  33           WindowResizer::kBoundsChangeDirection_Horizontal |
  34           WindowResizer::kBoundsChangeDirection_Vertical;
  35       break;
  36     case HTTOP:
  37     case HTTOPRIGHT:
  38     case HTBOTTOM:
  39       pos_change_direction |= WindowResizer::kBoundsChangeDirection_Vertical;
  40       break;
  41     case HTBOTTOMLEFT:
  42     case HTRIGHT:
  43     case HTLEFT:
  44       pos_change_direction |= WindowResizer::kBoundsChangeDirection_Horizontal;
  45       break;
  46     default:
  47       break;
  48   }
  49   return pos_change_direction;
  50 }
  51
  52 int GetSizeChangeDirectionForWindowComponent(int window_component) {
  53   int size_change_direction = WindowResizer::kBoundsChangeDirection_None;
  54   switch (window_component) {
  55     case HTTOPLEFT:
  56     case HTTOPRIGHT:
  57     case HTBOTTOMLEFT:
  58     case HTBOTTOMRIGHT:
  59     case HTGROWBOX:
  60     case HTCAPTION:
  61       size_change_direction |=
  62           WindowResizer::kBoundsChangeDirection_Horizontal |
  63           WindowResizer::kBoundsChangeDirection_Vertical;
  64       break;
  65     case HTTOP:
  66     case HTBOTTOM:
  67       size_change_direction |= WindowResizer::kBoundsChangeDirection_Vertical;
  68       break;
  69     case HTRIGHT:
  70     case HTLEFT:
  71       size_change_direction |= WindowResizer::kBoundsChangeDirection_Horizontal;
  72       break;
  73     default:
  74       break;
  75   }
  76   return size_change_direction;
  77 }
  78
  79 // Returns true for resize components along the right edge, where a drag in
  80 // positive x will make the window larger.
  81 bool IsRightEdge(int window_component) {
  82   return window_component == HTTOPRIGHT ||
  83       window_component == HTRIGHT ||
  84       window_component == HTBOTTOMRIGHT ||
  85       window_component == HTGROWBOX;
  86 }
  87
  88 }  // namespace
  89
  90 // static
  91 const int WindowResizer::kBoundsChange_None = 0;
  92 // static
  93 const int WindowResizer::kBoundsChange_Repositions = 1;
  94 // static
  95 const int WindowResizer::kBoundsChange_Resizes = 2;
  96
  97 // static
  98 const int WindowResizer::kBoundsChangeDirection_None = 0;
  99 // static
 100 const int WindowResizer::kBoundsChangeDirection_Horizontal = 1;
 101 // static
 102 const int WindowResizer::kBoundsChangeDirection_Vertical = 2;
 103
 104 WindowResizer::Details::Details()
 105     : window(NULL),
 106       window_component(HTNOWHERE),
 107       bounds_change(0),
 108       position_change_direction(0),
 109       size_change_direction(0),
 110       is_resizable(false) {
 111 }
 112
 113 WindowResizer::Details::Details(aura::Window* window,
 114                                 const gfx::Point& location,
 115                                 int window_component)
 116     : window(window),
 117       initial_bounds_in_parent(window->bounds()),
 118       restore_bounds(gfx::Rect()),
 119       initial_location_in_parent(location),
 120       initial_opacity(window->layer()->opacity()),
 121       window_component(window_component),
 122       bounds_change(GetBoundsChangeForWindowComponent(window_component)),
 123       position_change_direction(
 124           GetPositionChangeDirectionForWindowComponent(window_component)),
 125       size_change_direction(
 126           GetSizeChangeDirectionForWindowComponent(window_component)),
 127       is_resizable(bounds_change != kBoundsChangeDirection_None) {
 128   if (wm::IsWindowNormal(window) &&
 129       GetRestoreBoundsInScreen(window) &&
 130       window_component == HTCAPTION)
 131     restore_bounds = *GetRestoreBoundsInScreen(window);
 132 }
 133
 134 WindowResizer::Details::~Details() {
 135 }
 136
 137 WindowResizer::WindowResizer() {
 138 }
 139
 140 WindowResizer::~WindowResizer() {
 141 }
 142
 143 // static
 144 int WindowResizer::GetBoundsChangeForWindowComponent(int component) {
 145   int bounds_change = WindowResizer::kBoundsChange_None;
 146   switch (component) {
 147     case HTTOPLEFT:
 148     case HTTOP:
 149     case HTTOPRIGHT:
 150     case HTLEFT:
 151     case HTBOTTOMLEFT:
 152       bounds_change |= WindowResizer::kBoundsChange_Repositions |
 153                       WindowResizer::kBoundsChange_Resizes;
 154       break;
 155     case HTCAPTION:
 156       bounds_change |= WindowResizer::kBoundsChange_Repositions;
 157       break;
 158     case HTRIGHT:
 159     case HTBOTTOMRIGHT:
 160     case HTBOTTOM:
 161     case HTGROWBOX:
 162       bounds_change |= WindowResizer::kBoundsChange_Resizes;
 163       break;
 164     default:
 165       break;
 166   }
 167   return bounds_change;
 168 }
 169
 170 // static
 171 gfx::Rect WindowResizer::CalculateBoundsForDrag(
 172     const Details& details,
 173     const gfx::Point& passed_location) {
 174   if (!details.is_resizable)
 175     return details.initial_bounds_in_parent;
 176
 177   gfx::Point location = passed_location;
 178   gfx::Rect work_area =
 179       ScreenAsh::GetDisplayWorkAreaBoundsInParent(details.window);
 180
 181   int delta_x = location.x() - details.initial_location_in_parent.x();
 182   int delta_y = location.y() - details.initial_location_in_parent.y();
 183
 184   // The minimize size constraint may limit how much we change the window
 185   // position.  For example, dragging the left edge to the right should stop
 186   // repositioning the window when the minimize size is reached.
 187   gfx::Size size = GetSizeForDrag(details, &delta_x, &delta_y);
 188   gfx::Point origin = GetOriginForDrag(details, delta_x, delta_y);
 189   gfx::Rect new_bounds(origin, size);
 190
 191   // Sizing has to keep the result on the screen. Note that this correction
 192   // has to come first since it might have an impact on the origin as well as
 193   // on the size.
 194   if (details.bounds_change & kBoundsChange_Resizes) {
 195     if (details.size_change_direction & kBoundsChangeDirection_Horizontal) {
 196       if (IsRightEdge(details.window_component) &&
 197           new_bounds.right() < work_area.x() + kMinimumOnScreenArea) {
 198         int delta = work_area.x() + kMinimumOnScreenArea - new_bounds.right();
 199         new_bounds.set_width(new_bounds.width() + delta);
 200       } else if (new_bounds.x() > work_area.right() - kMinimumOnScreenArea) {
 201         int width = new_bounds.right() - work_area.right() +
 202                     kMinimumOnScreenArea;
 203         new_bounds.set_x(work_area.right() - kMinimumOnScreenArea);
 204         new_bounds.set_width(width);
 205       }
 206     }
 207     if (details.size_change_direction & kBoundsChangeDirection_Vertical) {
 208       if (!IsBottomEdge(details.window_component) &&
 209           new_bounds.y() > work_area.bottom() - kMinimumOnScreenArea) {
 210         int height = new_bounds.bottom() - work_area.bottom() +
 211                      kMinimumOnScreenArea;
 212         new_bounds.set_y(work_area.bottom() - kMinimumOnScreenArea);
 213         new_bounds.set_height(height);
 214       } else if (details.window_component == HTBOTTOM ||
 215                  details.window_component == HTBOTTOMRIGHT ||
 216                  details.window_component == HTBOTTOMLEFT) {
 217         // Update bottom edge to stay in the work area when we are resizing
 218         // by dragging the bottom edge or corners.
 219         if (new_bounds.bottom() > work_area.bottom())
 220           new_bounds.Inset(0, 0, 0,
 221                            new_bounds.bottom() - work_area.bottom());
 222       }
 223     }
 224     if (details.bounds_change & kBoundsChange_Repositions &&
 225         new_bounds.y() < 0) {
 226       int delta = new_bounds.y();
 227       new_bounds.set_y(0);
 228       new_bounds.set_height(new_bounds.height() + delta);
 229     }
 230   }
 231
 232   if (details.bounds_change & kBoundsChange_Repositions) {
 233     // When we might want to reposition a window which is also restored to its
 234     // previous size, to keep the cursor within the dragged window.
 235     if (!details.restore_bounds.IsEmpty()) {
 236       // However - it is not desirable to change the origin if the window would
 237       // be still hit by the cursor.
 238       if (details.initial_location_in_parent.x() >
 239           details.initial_bounds_in_parent.x() + details.restore_bounds.width())
 240         new_bounds.set_x(location.x() - details.restore_bounds.width() / 2);
 241     }
 242
 243     // Make sure that |new_bounds| doesn't leave any of the displays.  Note that
 244     // the |work_area| above isn't good for this check since it is the work area
 245     // for the current display but the window can move to a different one.
 246     aura::Window* parent = details.window->parent();
 247     gfx::Rect new_bounds_in_screen =
 248         ScreenAsh::ConvertRectToScreen(parent, new_bounds);
 249     const gfx::Display& display =
 250         Shell::GetScreen()->GetDisplayMatching(new_bounds_in_screen);
 251     gfx::Rect screen_work_area = display.work_area();
 252     screen_work_area.Inset(kMinimumOnScreenArea, 0);
 253     if (!screen_work_area.Intersects(new_bounds_in_screen)) {
 254       // Make sure that the x origin does not leave the current display.
 255       new_bounds_in_screen.set_x(
 256           std::max(screen_work_area.x() - new_bounds.width(),
 257                    std::min(screen_work_area.right(),
 258                             new_bounds_in_screen.x())));
 259       new_bounds =
 260           ScreenAsh::ConvertRectFromScreen(parent, new_bounds_in_screen);
 261     }
 262   }
 263
 264   return new_bounds;
 265 }
 266
 267 // static
 268 bool WindowResizer::IsBottomEdge(int window_component) {
 269   return window_component == HTBOTTOMLEFT ||
 270       window_component == HTBOTTOM ||
 271       window_component == HTBOTTOMRIGHT ||
 272       window_component == HTGROWBOX;
 273 }
 274
 275 // static
 276 gfx::Point WindowResizer::GetOriginForDrag(const Details& details,
 277                                            int delta_x,
 278                                            int delta_y) {
 279   gfx::Point origin = details.initial_bounds_in_parent.origin();
 280   if (details.bounds_change & kBoundsChange_Repositions) {
 281     int pos_change_direction =
 282         GetPositionChangeDirectionForWindowComponent(details.window_component);
 283     if (pos_change_direction & kBoundsChangeDirection_Horizontal)
 284       origin.Offset(delta_x, 0);
 285     if (pos_change_direction & kBoundsChangeDirection_Vertical)
 286       origin.Offset(0, delta_y);
 287   }
 288   return origin;
 289 }
 290
 291 // static
 292 gfx::Size WindowResizer::GetSizeForDrag(const Details& details,
 293                                         int* delta_x,
 294                                         int* delta_y) {
 295   gfx::Size size = details.initial_bounds_in_parent.size();
 296   if (details.bounds_change & kBoundsChange_Resizes) {
 297     gfx::Size min_size = details.window->delegate()->GetMinimumSize();
 298     size.SetSize(GetWidthForDrag(details, min_size.width(), delta_x),
 299                  GetHeightForDrag(details, min_size.height(), delta_y));
 300   } else if (!details.restore_bounds.IsEmpty()) {
 301     size = details.restore_bounds.size();
 302   }
 303   return size;
 304 }
 305
 306 // static
 307 int WindowResizer::GetWidthForDrag(const Details& details,
 308                                    int min_width,
 309                                    int* delta_x) {
 310   int width = details.initial_bounds_in_parent.width();
 311   if (details.size_change_direction & kBoundsChangeDirection_Horizontal) {
 312     // Along the right edge, positive delta_x increases the window size.
 313     int x_multiplier = IsRightEdge(details.window_component) ? 1 : -1;
 314     width += x_multiplier * (*delta_x);
 315
 316     // Ensure we don't shrink past the minimum width and clamp delta_x
 317     // for the window origin computation.
 318     if (width < min_width) {
 319       width = min_width;
 320       *delta_x = -x_multiplier * (details.initial_bounds_in_parent.width() -
 321                                   min_width);
 322     }
 323
 324     // And don't let the window go bigger than the display.
 325     int max_width = Shell::GetScreen()->GetDisplayNearestWindow(
 326         details.window).bounds().width();
 327     gfx::Size max_size = details.window->delegate()->GetMaximumSize();
 328     if (max_size.width() != 0)
 329       max_width = std::min(max_width, max_size.width());
 330     if (width > max_width) {
 331       width = max_width;
 332       *delta_x = -x_multiplier * (details.initial_bounds_in_parent.width() -
 333                                   max_width);
 334     }
 335   }
 336   return width;
 337 }
 338
 339 // static
 340 int WindowResizer::GetHeightForDrag(const Details& details,
 341                                     int min_height,
 342                                     int* delta_y) {
 343   int height = details.initial_bounds_in_parent.height();
 344   if (details.size_change_direction & kBoundsChangeDirection_Vertical) {
 345     // Along the bottom edge, positive delta_y increases the window size.
 346     int y_multiplier = IsBottomEdge(details.window_component) ? 1 : -1;
 347     height += y_multiplier * (*delta_y);
 348
 349     // Ensure we don't shrink past the minimum height and clamp delta_y
 350     // for the window origin computation.
 351     if (height < min_height) {
 352       height = min_height;
 353       *delta_y = -y_multiplier * (details.initial_bounds_in_parent.height() -
 354                                   min_height);
 355     }
 356
 357     // And don't let the window go bigger than the display.
 358     int max_height = Shell::GetScreen()->GetDisplayNearestWindow(
 359         details.window).bounds().height();
 360     gfx::Size max_size = details.window->delegate()->GetMaximumSize();
 361     if (max_size.height() != 0)
 362       max_height = std::min(max_height, max_size.height());
 363     if (height > max_height) {
 364       height = max_height;
 365       *delta_y = -y_multiplier * (details.initial_bounds_in_parent.height() -
 366                                   max_height);
 367     }
 368   }
 369   return height;
 370 }
 371
 372 }  // namespace aura