ash/wm/drag_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/drag_window_resizer.h"
   6
   7 #include "ash/display/mouse_cursor_event_filter.h"
   8 #include "ash/screen_util.h"
   9 #include "ash/shell.h"
  10 #include "ash/wm/coordinate_conversion.h"
  11 #include "ash/wm/drag_window_controller.h"
  12 #include "ash/wm/window_state.h"
  13 #include "ash/wm/window_util.h"
  14 #include "base/memory/weak_ptr.h"
  15 #include "ui/aura/client/aura_constants.h"
  16 #include "ui/aura/env.h"
  17 #include "ui/aura/window.h"
  18 #include "ui/aura/window_delegate.h"
  19 #include "ui/aura/window_event_dispatcher.h"
  20 #include "ui/base/hit_test.h"
  21 #include "ui/base/ui_base_types.h"
  22 #include "ui/gfx/screen.h"
  23 #include "ui/wm/core/coordinate_conversion.h"
  24 #include "ui/wm/core/window_util.h"
  25
  26 namespace ash {
  27 namespace {
  28
  29 // The maximum opacity of the drag phantom window.
  30 const float kMaxOpacity = 0.8f;
  31
  32 // Returns true if Ash has more than one root window.
  33 bool HasSecondaryRootWindows() {
  34   return Shell::GetAllRootWindows().size() > 1;
  35 }
  36
  37 // When there are more than one root windows, returns all root windows which are
  38 // not |root_window|. Returns an empty vector if only one root window exists.
  39 aura::Window::Windows GetOtherRootWindows(aura::Window* root_window) {
  40   aura::Window::Windows root_windows = Shell::GetAllRootWindows();
  41   aura::Window::Windows other_root_windows;
  42   if (root_windows.size() < 2)
  43     return other_root_windows;
  44   for (size_t i = 0; i < root_windows.size(); ++i) {
  45     if (root_windows[i] != root_window)
  46       other_root_windows.push_back(root_windows[i]);
  47   }
  48   return other_root_windows;
  49 }
  50
  51 }  // namespace
  52
  53 // static
  54 DragWindowResizer* DragWindowResizer::instance_ = NULL;
  55
  56 DragWindowResizer::~DragWindowResizer() {
  57   if (window_state_)
  58     window_state_->DeleteDragDetails();
  59   Shell* shell = Shell::GetInstance();
  60   shell->mouse_cursor_filter()->set_mouse_warp_enabled(true);
  61   shell->mouse_cursor_filter()->HideSharedEdgeIndicator();
  62   if (instance_ == this)
  63     instance_ = NULL;
  64 }
  65
  66 // static
  67 DragWindowResizer* DragWindowResizer::Create(
  68     WindowResizer* next_window_resizer,
  69     wm::WindowState* window_state) {
  70   return new DragWindowResizer(next_window_resizer, window_state);
  71 }
  72
  73 void DragWindowResizer::Drag(const gfx::Point& location, int event_flags) {
  74   base::WeakPtr<DragWindowResizer> resizer(weak_ptr_factory_.GetWeakPtr());
  75   next_window_resizer_->Drag(location, event_flags);
  76
  77   if (!resizer)
  78     return;
  79
  80   last_mouse_location_ = location;
  81   // Show a phantom window for dragging in another root window.
  82   if (HasSecondaryRootWindows()) {
  83     gfx::Point location_in_screen = location;
  84     ::wm::ConvertPointToScreen(GetTarget()->parent(), &location_in_screen);
  85     const bool in_original_root =
  86         wm::GetRootWindowAt(location_in_screen) == GetTarget()->GetRootWindow();
  87     UpdateDragWindow(GetTarget()->bounds(), in_original_root);
  88   } else {
  89     drag_window_controllers_.clear();
  90   }
  91 }
  92
  93 void DragWindowResizer::CompleteDrag() {
  94   next_window_resizer_->CompleteDrag();
  95
  96   GetTarget()->layer()->SetOpacity(details().initial_opacity);
  97   drag_window_controllers_.clear();
  98
  99   // Check if the destination is another display.
 100   gfx::Point last_mouse_location_in_screen = last_mouse_location_;
 101   ::wm::ConvertPointToScreen(GetTarget()->parent(),
 102                              &last_mouse_location_in_screen);
 103   gfx::Screen* screen = Shell::GetScreen();
 104   const gfx::Display dst_display =
 105       screen->GetDisplayNearestPoint(last_mouse_location_in_screen);
 106
 107   if (dst_display.id() !=
 108       screen->GetDisplayNearestWindow(GetTarget()->GetRootWindow()).id()) {
 109     // Adjust the size and position so that it doesn't exceed the size of
 110     // work area.
 111     const gfx::Size& size = dst_display.work_area().size();
 112     gfx::Rect bounds = GetTarget()->bounds();
 113     if (bounds.width() > size.width()) {
 114       int diff = bounds.width() - size.width();
 115       bounds.set_x(bounds.x() + diff / 2);
 116       bounds.set_width(size.width());
 117     }
 118     if (bounds.height() > size.height())
 119       bounds.set_height(size.height());
 120
 121     gfx::Rect dst_bounds =
 122         ScreenUtil::ConvertRectToScreen(GetTarget()->parent(), bounds);
 123
 124     // Adjust the position so that the cursor is on the window.
 125     if (!dst_bounds.Contains(last_mouse_location_in_screen)) {
 126       if (last_mouse_location_in_screen.x() < dst_bounds.x())
 127         dst_bounds.set_x(last_mouse_location_in_screen.x());
 128       else if (last_mouse_location_in_screen.x() > dst_bounds.right())
 129         dst_bounds.set_x(
 130             last_mouse_location_in_screen.x() - dst_bounds.width());
 131     }
 132     ash::wm::AdjustBoundsToEnsureMinimumWindowVisibility(
 133         dst_display.bounds(), &dst_bounds);
 134
 135     GetTarget()->SetBoundsInScreen(dst_bounds, dst_display);
 136   }
 137 }
 138
 139 void DragWindowResizer::RevertDrag() {
 140   next_window_resizer_->RevertDrag();
 141
 142   drag_window_controllers_.clear();
 143   GetTarget()->layer()->SetOpacity(details().initial_opacity);
 144 }
 145
 146 DragWindowResizer::DragWindowResizer(WindowResizer* next_window_resizer,
 147                                      wm::WindowState* window_state)
 148     : WindowResizer(window_state),
 149       next_window_resizer_(next_window_resizer),
 150       weak_ptr_factory_(this) {
 151   // The pointer should be confined in one display during resizing a window
 152   // because the window cannot span two displays at the same time anyway. The
 153   // exception is window/tab dragging operation. During that operation,
 154   // |mouse_warp_mode_| should be set to WARP_DRAG so that the user could move a
 155   // window/tab to another display.
 156   MouseCursorEventFilter* mouse_cursor_filter =
 157       Shell::GetInstance()->mouse_cursor_filter();
 158   mouse_cursor_filter->set_mouse_warp_enabled(ShouldAllowMouseWarp());
 159   if (ShouldAllowMouseWarp())
 160     mouse_cursor_filter->ShowSharedEdgeIndicator(GetTarget()->GetRootWindow());
 161   instance_ = this;
 162 }
 163
 164 void DragWindowResizer::UpdateDragWindow(const gfx::Rect& bounds,
 165                                          bool in_original_root) {
 166   if (details().window_component != HTCAPTION || !ShouldAllowMouseWarp())
 167     return;
 168
 169   // It's available. Show a phantom window on the display if needed.
 170   aura::Window::Windows other_roots =
 171       GetOtherRootWindows(GetTarget()->GetRootWindow());
 172   size_t drag_window_controller_count = 0;
 173   for (size_t i = 0; i < other_roots.size(); ++i) {
 174     aura::Window* another_root = other_roots[i];
 175     const gfx::Rect root_bounds_in_screen(another_root->GetBoundsInScreen());
 176     const gfx::Rect bounds_in_screen =
 177       ScreenUtil::ConvertRectToScreen(GetTarget()->parent(), bounds);
 178     gfx::Rect bounds_in_another_root =
 179         gfx::IntersectRects(root_bounds_in_screen, bounds_in_screen);
 180     const float fraction_in_another_window =
 181         (bounds_in_another_root.width() * bounds_in_another_root.height()) /
 182         static_cast<float>(bounds.width() * bounds.height());
 183
 184     if (fraction_in_another_window > 0) {
 185       if (drag_window_controllers_.size() < ++drag_window_controller_count)
 186         drag_window_controllers_.resize(drag_window_controller_count);
 187       ScopedVector<DragWindowController>::reference drag_window_controller =
 188         drag_window_controllers_.back();
 189       if (!drag_window_controller) {
 190         drag_window_controller = new DragWindowController(GetTarget());
 191         // Always show the drag phantom on the |another_root| window.
 192         drag_window_controller->SetDestinationDisplay(
 193             Shell::GetScreen()->GetDisplayNearestWindow(another_root));
 194         drag_window_controller->Show();
 195       } else {
 196         // No animation.
 197         drag_window_controller->SetBounds(bounds_in_screen);
 198       }
 199       const float phantom_opacity =
 200           !in_original_root ? 1 : (kMaxOpacity * fraction_in_another_window);
 201       const float window_opacity =
 202           in_original_root ? 1
 203                            : (kMaxOpacity * (1 - fraction_in_another_window));
 204       drag_window_controller->SetOpacity(phantom_opacity);
 205       GetTarget()->layer()->SetOpacity(window_opacity);
 206     } else {
 207       GetTarget()->layer()->SetOpacity(1.0f);
 208     }
 209   }
 210
 211   // If we have more drag window controllers allocated than needed, release the
 212   // excess controllers by shrinking the vector |drag_window_controller_|.
 213   DCHECK_GE(drag_window_controllers_.size(), drag_window_controller_count);
 214   if (drag_window_controllers_.size() > drag_window_controller_count)
 215     drag_window_controllers_.resize(drag_window_controller_count);
 216 }
 217
 218 bool DragWindowResizer::ShouldAllowMouseWarp() {
 219   return details().window_component == HTCAPTION &&
 220          !::wm::GetTransientParent(GetTarget()) &&
 221          wm::IsWindowUserPositionable(GetTarget());
 222 }
 223
 224 }  // namespace ash