src/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/window_util.h"
  24
  25 namespace ash {
  26 namespace {
  27
  28 // The maximum opacity of the drag phantom window.
  29 const float kMaxOpacity = 0.8f;
  30
  31 // Returns true if Ash has more than one root window.
  32 bool HasSecondaryRootWindow() {
  33   return Shell::GetAllRootWindows().size() > 1;
  34 }
  35
  36 // When there are two root windows, returns one of the root windows which is not
  37 // |root_window|. Returns NULL if only one root window exists.
  38 aura::Window* GetAnotherRootWindow(aura::Window* root_window) {
  39   aura::Window::Windows root_windows = Shell::GetAllRootWindows();
  40   if (root_windows.size() < 2)
  41     return NULL;
  42   DCHECK_EQ(2U, root_windows.size());
  43   if (root_windows[0] == root_window)
  44     return root_windows[1];
  45   return root_windows[0];
  46 }
  47
  48 }  // namespace
  49
  50 // static
  51 DragWindowResizer* DragWindowResizer::instance_ = NULL;
  52
  53 DragWindowResizer::~DragWindowResizer() {
  54   if (window_state_)
  55     window_state_->DeleteDragDetails();
  56   Shell* shell = Shell::GetInstance();
  57   shell->mouse_cursor_filter()->set_mouse_warp_mode(
  58       MouseCursorEventFilter::WARP_ALWAYS);
  59   shell->mouse_cursor_filter()->HideSharedEdgeIndicator();
  60   if (instance_ == this)
  61     instance_ = NULL;
  62 }
  63
  64 // static
  65 DragWindowResizer* DragWindowResizer::Create(
  66     WindowResizer* next_window_resizer,
  67     wm::WindowState* window_state) {
  68   return new DragWindowResizer(next_window_resizer, window_state);
  69 }
  70
  71 void DragWindowResizer::Drag(const gfx::Point& location, int event_flags) {
  72   base::WeakPtr<DragWindowResizer> resizer(weak_ptr_factory_.GetWeakPtr());
  73   next_window_resizer_->Drag(location, event_flags);
  74
  75   if (!resizer)
  76     return;
  77
  78   last_mouse_location_ = location;
  79   // Show a phantom window for dragging in another root window.
  80   if (HasSecondaryRootWindow()) {
  81     gfx::Point location_in_screen = location;
  82     wm::ConvertPointToScreen(GetTarget()->parent(), &location_in_screen);
  83     const bool in_original_root =
  84         wm::GetRootWindowAt(location_in_screen) == GetTarget()->GetRootWindow();
  85     UpdateDragWindow(GetTarget()->bounds(), in_original_root);
  86   } else {
  87     drag_window_controller_.reset();
  88   }
  89 }
  90
  91 void DragWindowResizer::CompleteDrag() {
  92   next_window_resizer_->CompleteDrag();
  93
  94   GetTarget()->layer()->SetOpacity(details().initial_opacity);
  95   drag_window_controller_.reset();
  96
  97   // Check if the destination is another display.
  98   gfx::Point last_mouse_location_in_screen = last_mouse_location_;
  99   wm::ConvertPointToScreen(GetTarget()->parent(),
 100                            &last_mouse_location_in_screen);
 101   gfx::Screen* screen = Shell::GetScreen();
 102   const gfx::Display dst_display =
 103       screen->GetDisplayNearestPoint(last_mouse_location_in_screen);
 104
 105   if (dst_display.id() !=
 106       screen->GetDisplayNearestWindow(GetTarget()->GetRootWindow()).id()) {
 107     // Adjust the size and position so that it doesn't exceed the size of
 108     // work area.
 109     const gfx::Size& size = dst_display.work_area().size();
 110     gfx::Rect bounds = GetTarget()->bounds();
 111     if (bounds.width() > size.width()) {
 112       int diff = bounds.width() - size.width();
 113       bounds.set_x(bounds.x() + diff / 2);
 114       bounds.set_width(size.width());
 115     }
 116     if (bounds.height() > size.height())
 117       bounds.set_height(size.height());
 118
 119     gfx::Rect dst_bounds =
 120         ScreenUtil::ConvertRectToScreen(GetTarget()->parent(), bounds);
 121
 122     // Adjust the position so that the cursor is on the window.
 123     if (!dst_bounds.Contains(last_mouse_location_in_screen)) {
 124       if (last_mouse_location_in_screen.x() < dst_bounds.x())
 125         dst_bounds.set_x(last_mouse_location_in_screen.x());
 126       else if (last_mouse_location_in_screen.x() > dst_bounds.right())
 127         dst_bounds.set_x(
 128             last_mouse_location_in_screen.x() - dst_bounds.width());
 129     }
 130     ash::wm::AdjustBoundsToEnsureMinimumWindowVisibility(
 131         dst_display.bounds(), &dst_bounds);
 132
 133     GetTarget()->SetBoundsInScreen(dst_bounds, dst_display);
 134   }
 135 }
 136
 137 void DragWindowResizer::RevertDrag() {
 138   next_window_resizer_->RevertDrag();
 139
 140   drag_window_controller_.reset();
 141   GetTarget()->layer()->SetOpacity(details().initial_opacity);
 142 }
 143
 144 DragWindowResizer::DragWindowResizer(WindowResizer* next_window_resizer,
 145                                      wm::WindowState* window_state)
 146     : WindowResizer(window_state),
 147       next_window_resizer_(next_window_resizer),
 148       weak_ptr_factory_(this) {
 149   // The pointer should be confined in one display during resizing a window
 150   // because the window cannot span two displays at the same time anyway. The
 151   // exception is window/tab dragging operation. During that operation,
 152   // |mouse_warp_mode_| should be set to WARP_DRAG so that the user could move a
 153   // window/tab to another display.
 154   MouseCursorEventFilter* mouse_cursor_filter =
 155       Shell::GetInstance()->mouse_cursor_filter();
 156   mouse_cursor_filter->set_mouse_warp_mode(
 157       ShouldAllowMouseWarp() ?
 158       MouseCursorEventFilter::WARP_DRAG : MouseCursorEventFilter::WARP_NONE);
 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* another_root =
 171       GetAnotherRootWindow(GetTarget()->GetRootWindow());
 172   const gfx::Rect root_bounds_in_screen(another_root->GetBoundsInScreen());
 173   const gfx::Rect bounds_in_screen =
 174       ScreenUtil::ConvertRectToScreen(GetTarget()->parent(), bounds);
 175   gfx::Rect bounds_in_another_root =
 176       gfx::IntersectRects(root_bounds_in_screen, bounds_in_screen);
 177   const float fraction_in_another_window =
 178       (bounds_in_another_root.width() * bounds_in_another_root.height()) /
 179       static_cast<float>(bounds.width() * bounds.height());
 180
 181   if (fraction_in_another_window > 0) {
 182     if (!drag_window_controller_) {
 183       drag_window_controller_.reset(
 184           new DragWindowController(GetTarget()));
 185       // Always show the drag phantom on the |another_root| window.
 186       drag_window_controller_->SetDestinationDisplay(
 187           Shell::GetScreen()->GetDisplayNearestWindow(another_root));
 188       drag_window_controller_->Show();
 189     } else {
 190       // No animation.
 191       drag_window_controller_->SetBounds(bounds_in_screen);
 192     }
 193     const float phantom_opacity =
 194       !in_original_root ? 1 : (kMaxOpacity * fraction_in_another_window);
 195     const float window_opacity =
 196         in_original_root ? 1 : (kMaxOpacity * (1 - fraction_in_another_window));
 197     drag_window_controller_->SetOpacity(phantom_opacity);
 198     GetTarget()->layer()->SetOpacity(window_opacity);
 199   } else {
 200     drag_window_controller_.reset();
 201     GetTarget()->layer()->SetOpacity(1.0f);
 202   }
 203 }
 204
 205 bool DragWindowResizer::ShouldAllowMouseWarp() {
 206   return (details().window_component == HTCAPTION) &&
 207       !::wm::GetTransientParent(GetTarget()) &&
 208       (GetTarget()->type() == ui::wm::WINDOW_TYPE_NORMAL ||
 209        GetTarget()->type() == ui::wm::WINDOW_TYPE_PANEL);
 210 }
 211
 212 }  // namespace ash