src/ui/views/widget/desktop_aura/x11_desktop_handler.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 "ui/views/widget/desktop_aura/x11_desktop_handler.h"
   6
   7 #include <X11/Xatom.h>
   8 #include <X11/Xlib.h>
   9
  10 #include "base/message_loop/message_loop.h"
  11 #include "ui/aura/env.h"
  12 #include "ui/aura/window_event_dispatcher.h"
  13 #include "ui/base/x/x11_foreign_window_manager.h"
  14 #include "ui/base/x/x11_menu_list.h"
  15 #include "ui/base/x/x11_util.h"
  16 #include "ui/events/platform/platform_event_source.h"
  17 #include "ui/gfx/x/x11_error_tracker.h"
  18 #include "ui/views/ime/input_method.h"
  19 #include "ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h"
  20
  21 namespace {
  22
  23 const char* kAtomsToCache[] = {
  24   "_NET_ACTIVE_WINDOW",
  25   NULL
  26 };
  27
  28 // Our global instance. Deleted when our Env() is deleted.
  29 views::X11DesktopHandler* g_handler = NULL;
  30
  31 }  // namespace
  32
  33 namespace views {
  34
  35 // static
  36 X11DesktopHandler* X11DesktopHandler::get() {
  37   if (!g_handler)
  38     g_handler = new X11DesktopHandler;
  39
  40   return g_handler;
  41 }
  42
  43 X11DesktopHandler::X11DesktopHandler()
  44     : xdisplay_(gfx::GetXDisplay()),
  45       x_root_window_(DefaultRootWindow(xdisplay_)),
  46       wm_user_time_ms_(0),
  47       current_window_(None),
  48       current_window_active_state_(NOT_ACTIVE),
  49       atom_cache_(xdisplay_, kAtomsToCache),
  50       wm_supports_active_window_(false) {
  51   if (ui::PlatformEventSource::GetInstance())
  52     ui::PlatformEventSource::GetInstance()->AddPlatformEventDispatcher(this);
  53   aura::Env::GetInstance()->AddObserver(this);
  54
  55   XWindowAttributes attr;
  56   XGetWindowAttributes(xdisplay_, x_root_window_, &attr);
  57   XSelectInput(xdisplay_, x_root_window_,
  58                attr.your_event_mask | PropertyChangeMask |
  59                StructureNotifyMask | SubstructureNotifyMask);
  60
  61   wm_supports_active_window_ =
  62       ui::WmSupportsHint(atom_cache_.GetAtom("_NET_ACTIVE_WINDOW"));
  63 }
  64
  65 X11DesktopHandler::~X11DesktopHandler() {
  66   aura::Env::GetInstance()->RemoveObserver(this);
  67   if (ui::PlatformEventSource::GetInstance())
  68     ui::PlatformEventSource::GetInstance()->RemovePlatformEventDispatcher(this);
  69 }
  70
  71 void X11DesktopHandler::ActivateWindow(::Window window) {
  72   if (current_window_ == window &&
  73       current_window_active_state_ == NOT_ACTIVE) {
  74     // |window| is most likely still active wrt to the X server. Undo the
  75     // changes made in DeactivateWindow().
  76     OnActiveWindowChanged(window, ACTIVE);
  77
  78     // Go through the regular activation path such that calling
  79     // DeactivateWindow() and ActivateWindow() immediately afterwards results
  80     // in an active X window.
  81   }
  82
  83   XRaiseWindow(xdisplay_, window);
  84
  85   if (wm_supports_active_window_) {
  86     DCHECK_EQ(gfx::GetXDisplay(), xdisplay_);
  87
  88     XEvent xclient;
  89     memset(&xclient, 0, sizeof(xclient));
  90     xclient.type = ClientMessage;
  91     xclient.xclient.window = window;
  92     xclient.xclient.message_type = atom_cache_.GetAtom("_NET_ACTIVE_WINDOW");
  93     xclient.xclient.format = 32;
  94     xclient.xclient.data.l[0] = 1;  // Specified we are an app.
  95     xclient.xclient.data.l[1] = wm_user_time_ms_;
  96     xclient.xclient.data.l[2] = None;
  97     xclient.xclient.data.l[3] = 0;
  98     xclient.xclient.data.l[4] = 0;
  99
 100     XSendEvent(xdisplay_, x_root_window_, False,
 101                SubstructureRedirectMask | SubstructureNotifyMask,
 102                &xclient);
 103   } else {
 104     // XRaiseWindow will not give input focus to the window. We now need to ask
 105     // the X server to do that. Note that the call will raise an X error if the
 106     // window is not mapped.
 107     XSetInputFocus(xdisplay_, window, RevertToParent, CurrentTime);
 108
 109     OnActiveWindowChanged(window, ACTIVE);
 110   }
 111 }
 112
 113 void X11DesktopHandler::DeactivateWindow(::Window window) {
 114   if (!IsActiveWindow(window))
 115     return;
 116
 117   XLowerWindow(xdisplay_, window);
 118
 119   // Per ICCCM: http://tronche.com/gui/x/icccm/sec-4.html#s-4.1.7
 120   // "Clients should not give up the input focus of their own volition.
 121   // They should ignore input that they receive instead."
 122   //
 123   // There is nothing else that we can do. Pretend that we have been
 124   // deactivated and ignore keyboard input in DesktopWindowTreeHostX11.
 125   OnActiveWindowChanged(window, NOT_ACTIVE);
 126 }
 127
 128 bool X11DesktopHandler::IsActiveWindow(::Window window) const {
 129   return window == current_window_ && current_window_active_state_ == ACTIVE;
 130 }
 131
 132 void X11DesktopHandler::ProcessXEvent(XEvent* event) {
 133   switch (event->type) {
 134     case FocusIn:
 135       if (current_window_ != event->xfocus.window)
 136         OnActiveWindowChanged(event->xfocus.window, ACTIVE);
 137       break;
 138     case FocusOut:
 139       if (current_window_ == event->xfocus.window)
 140         OnActiveWindowChanged(None, NOT_ACTIVE);
 141       break;
 142     default:
 143       NOTREACHED();
 144   }
 145 }
 146
 147 bool X11DesktopHandler::CanDispatchEvent(const ui::PlatformEvent& event) {
 148   return event->type == CreateNotify || event->type == DestroyNotify ||
 149          (event->type == PropertyNotify &&
 150           event->xproperty.window == x_root_window_);
 151 }
 152
 153 uint32_t X11DesktopHandler::DispatchEvent(const ui::PlatformEvent& event) {
 154   switch (event->type) {
 155     case PropertyNotify: {
 156       // Check for a change to the active window.
 157       CHECK_EQ(x_root_window_, event->xproperty.window);
 158       ::Atom active_window_atom = atom_cache_.GetAtom("_NET_ACTIVE_WINDOW");
 159       if (event->xproperty.atom == active_window_atom) {
 160         ::Window window;
 161         if (ui::GetXIDProperty(x_root_window_, "_NET_ACTIVE_WINDOW", &window) &&
 162             window) {
 163           OnActiveWindowChanged(window, ACTIVE);
 164         }
 165       }
 166       break;
 167     }
 168
 169     case CreateNotify:
 170       OnWindowCreatedOrDestroyed(event->type, event->xcreatewindow.window);
 171       break;
 172     case DestroyNotify:
 173       OnWindowCreatedOrDestroyed(event->type, event->xdestroywindow.window);
 174       break;
 175     default:
 176       NOTREACHED();
 177   }
 178
 179   return ui::POST_DISPATCH_NONE;
 180 }
 181
 182 void X11DesktopHandler::OnWindowInitialized(aura::Window* window) {
 183 }
 184
 185 void X11DesktopHandler::OnWillDestroyEnv() {
 186   g_handler = NULL;
 187   delete this;
 188 }
 189
 190 void X11DesktopHandler::OnActiveWindowChanged(::Window xid,
 191                                               ActiveState active_state) {
 192   if (current_window_ == xid && current_window_active_state_ == active_state)
 193     return;
 194
 195   if (current_window_active_state_ == ACTIVE) {
 196     DesktopWindowTreeHostX11* old_host =
 197         views::DesktopWindowTreeHostX11::GetHostForXID(current_window_);
 198     if (old_host)
 199       old_host->HandleNativeWidgetActivationChanged(false);
 200   }
 201
 202   // Update the current window ID to effectively change the active widget.
 203   current_window_ = xid;
 204   current_window_active_state_ = active_state;
 205
 206   if (active_state == ACTIVE) {
 207     DesktopWindowTreeHostX11* new_host =
 208         views::DesktopWindowTreeHostX11::GetHostForXID(xid);
 209     if (new_host)
 210       new_host->HandleNativeWidgetActivationChanged(true);
 211   }
 212 }
 213
 214 void X11DesktopHandler::OnWindowCreatedOrDestroyed(int event_type,
 215                                                    XID window) {
 216   // Menus created by Chrome can be drag and drop targets. Since they are
 217   // direct children of the screen root window and have override_redirect
 218   // we cannot use regular _NET_CLIENT_LIST_STACKING property to find them
 219   // and use a separate cache to keep track of them.
 220   // TODO(varkha): Implement caching of all top level X windows and their
 221   // coordinates and stacking order to eliminate repeated calls to the X server
 222   // during mouse movement, drag and shaping events.
 223   if (event_type == CreateNotify) {
 224     // The window might be destroyed if the message pump did not get a chance to
 225     // run but we can safely ignore the X error.
 226     gfx::X11ErrorTracker error_tracker;
 227     ui::XMenuList::GetInstance()->MaybeRegisterMenu(window);
 228   } else {
 229     ui::XMenuList::GetInstance()->MaybeUnregisterMenu(window);
 230   }
 231
 232   if (event_type == DestroyNotify) {
 233     // Notify the XForeignWindowManager that |window| has been destroyed.
 234     ui::XForeignWindowManager::GetInstance()->OnWindowDestroyed(window);
 235   }
 236 }
 237
 238 }  // namespace views