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 HasSecondaryRootWindow() {
  34   return Shell::GetAllRootWindows().size() > 1;
  35 }
  36
  37 // When there are two root windows, returns one of the root windows which is not
  38 // |root_window|. Returns NULL if only one root window exists.
  39 aura::Window* GetAnotherRootWindow(aura::Window* root_window) {
  40   aura::Window::Windows root_windows = Shell::GetAllRootWindows();
  41   if (root_windows.size() < 2)
  42     return NULL;
  43   DCHECK_EQ(2U, root_windows.size());
  44   if (root_windows[0] == root_window)
  45     return root_windows[1];
  46   return root_windows[0];
  47 }
  48
  49 }  // namespace
  50
  51 // static
  52 DragWindowResizer* DragWindowResizer::instance_ = NULL;
  53
  54 DragWindowResizer::~DragWindowResizer() {
  55   if (window_state_)
  56     window_state_->DeleteDragDetails();
  57   Shell* shell = Shell::GetInstance();
  58   shell->mouse_cursor_filter()->set_mouse_warp_mode(
  59       MouseCursorEventFilter::WARP_ALWAYS);
  60   shell->mouse_cursor_filter()->HideSharedEdgeIndicator();
  61   if (instance_ == this)
  62     instance_ = NULL;
  63 }
  64
  65 // static
  66 DragWindowResizer* DragWindowResizer::Create(
  67     WindowResizer* next_window_resizer,
  68     wm::WindowState* window_state) {
  69   return new DragWindowResizer(next_window_resizer, window_state);
  70 }
  71
  72 void DragWindowResizer::Drag(const gfx::Point& location, int event_flags) {
  73   base::WeakPtr<DragWindowResizer> resizer(weak_ptr_factory_.GetWeakPtr());
  74   next_window_resizer_->Drag(location, event_flags);
  75
  76   if (!resizer)
  77     return;
  78
  79   last_mouse_location_ = location;
  80   // Show a phantom window for dragging in another root window.
  81   if (HasSecondaryRootWindow()) {
  82     gfx::Point location_in_screen = location;
  83     ::wm::ConvertPointToScreen(GetTarget()->parent(), &location_in_screen);
  84     const bool in_original_root =
  85         wm::GetRootWindowAt(location_in_screen) == GetTarget()->GetRootWindow();
  86     UpdateDragWindow(GetTarget()->bounds(), in_original_root);
  87   } else {
  88     drag_window_controller_.reset();
  89   }
  90 }
  91
  92 void DragWindowResizer::CompleteDrag() {
  93   next_window_resizer_->CompleteDrag();
  94
  95   GetTarget()->layer()->SetOpacity(details().initial_opacity);
  96   drag_window_controller_.reset();
  97
  98   // Check if the destination is another display.
  99   gfx::Point last_mouse_location_in_screen = last_mouse_location_;
 100   ::wm::ConvertPointToScreen(GetTarget()->parent(),
 101                              &last_mouse_location_in_screen);
 102   gfx::Screen* screen = Shell::GetScreen();
 103   const gfx::Display dst_display =
 104       screen->GetDisplayNearestPoint(last_mouse_location_in_screen);
 105
 106   if (dst_display.id() !=
 107       screen->GetDisplayNearestWindow(GetTarget()->GetRootWindow()).id()) {
 108     // Adjust the size and position so that it doesn't exceed the size of
 109     // work area.
 110     const gfx::Size& size = dst_display.work_area().size();
 111     gfx::Rect bounds = GetTarget()->bounds();
 112     if (bounds.width() > size.width()) {
 113       int diff = bounds.width() - size.width();
 114       bounds.set_x(bounds.x() + diff / 2);
 115       bounds.set_width(size.width());
 116     }
 117     if (bounds.height() > size.height())
 118       bounds.set_height(size.height());
 119
 120     gfx::Rect dst_bounds =
 121         ScreenUtil::ConvertRectToScreen(GetTarget()->parent(), bounds);
 122
 123     // Adjust the position so that the cursor is on the window.
 124     if (!dst_bounds.Contains(last_mouse_location_in_screen)) {
 125       if (last_mouse_location_in_screen.x() < dst_bounds.x())
 126         dst_bounds.set_x(last_mouse_location_in_screen.x());
 127       else if (last_mouse_location_in_screen.x() > dst_bounds.right())
 128         dst_bounds.set_x(
 129             last_mouse_location_in_screen.x() - dst_bounds.width());
 130     }
 131     ash::wm::AdjustBoundsToEnsureMinimumWindowVisibility(
 132         dst_display.bounds(), &dst_bounds);
 133
 134     GetTarget()->SetBoundsInScreen(dst_bounds, dst_display);
 135   }
 136 }
 137
 138 void DragWindowResizer::RevertDrag() {
 139   next_window_resizer_->RevertDrag();
 140
 141   drag_window_controller_.reset();
 142   GetTarget()->layer()->SetOpacity(details().initial_opacity);
 143 }
 144
 145 DragWindowResizer::DragWindowResizer(WindowResizer* next_window_resizer,
 146                                      wm::WindowState* window_state)
 147     : WindowResizer(window_state),
 148       next_window_resizer_(next_window_resizer),
 149       weak_ptr_factory_(this) {
 150   // The pointer should be confined in one display during resizing a window
 151   // because the window cannot span two displays at the same time anyway. The
 152   // exception is window/tab dragging operation. During that operation,
 153   // |mouse_warp_mode_| should be set to WARP_DRAG so that the user could move a
 154   // window/tab to another display.
 155   MouseCursorEventFilter* mouse_cursor_filter =
 156       Shell::GetInstance()->mouse_cursor_filter();
 157   mouse_cursor_filter->set_mouse_warp_mode(
 158       ShouldAllowMouseWarp() ?
 159       MouseCursorEventFilter::WARP_DRAG : MouseCursorEventFilter::WARP_NONE);
 160   if (ShouldAllowMouseWarp())
 161     mouse_cursor_filter->ShowSharedEdgeIndicator(GetTarget()->GetRootWindow());
 162   instance_ = this;
 163 }
 164
 165 void DragWindowResizer::UpdateDragWindow(const gfx::Rect& bounds,
 166                                          bool in_original_root) {
 167   if (details().window_component != HTCAPTION || !ShouldAllowMouseWarp())
 168     return;
 169
 170   // It's available. Show a phantom window on the display if needed.
 171   aura::Window* another_root =
 172       GetAnotherRootWindow(GetTarget()->GetRootWindow());
 173   const gfx::Rect root_bounds_in_screen(another_root->GetBoundsInScreen());
 174   const gfx::Rect bounds_in_screen =
 175       ScreenUtil::ConvertRectToScreen(GetTarget()->parent(), bounds);
 176   gfx::Rect bounds_in_another_root =
 177       gfx::IntersectRects(root_bounds_in_screen, bounds_in_screen);
 178   const float fraction_in_another_window =
 179       (bounds_in_another_root.width() * bounds_in_another_root.height()) /
 180       static_cast<float>(bounds.width() * bounds.height());
 181
 182   if (fraction_in_another_window > 0) {
 183     if (!drag_window_controller_) {
 184       drag_window_controller_.reset(
 185           new DragWindowController(GetTarget()));
 186       // Always show the drag phantom on the |another_root| window.
 187       drag_window_controller_->SetDestinationDisplay(
 188           Shell::GetScreen()->GetDisplayNearestWindow(another_root));
 189       drag_window_controller_->Show();
 190     } else {
 191       // No animation.
 192       drag_window_controller_->SetBounds(bounds_in_screen);
 193     }
 194     const float phantom_opacity =
 195       !in_original_root ? 1 : (kMaxOpacity * fraction_in_another_window);
 196     const float window_opacity =
 197         in_original_root ? 1 : (kMaxOpacity * (1 - fraction_in_another_window));
 198     drag_window_controller_->SetOpacity(phantom_opacity);
 199     GetTarget()->layer()->SetOpacity(window_opacity);
 200   } else {
 201     drag_window_controller_.reset();
 202     GetTarget()->layer()->SetOpacity(1.0f);
 203   }
 204 }
 205
 206 bool DragWindowResizer::ShouldAllowMouseWarp() {
 207   return (details().window_component == HTCAPTION) &&
 208       !::wm::GetTransientParent(GetTarget()) &&
 209       (GetTarget()->type() == ui::wm::WINDOW_TYPE_NORMAL ||
 210        GetTarget()->type() == ui::wm::WINDOW_TYPE_PANEL);
 211 }
 212
 213 }  // namespace ash