Desktop Aura: Allow tab drags out of window.

ui/views/widget/x11_desktop_window_move_client.cc

Index: ui/views/widget/x11_desktop_window_move_client.cc
diff --git a/ui/views/widget/x11_desktop_window_move_client.cc b/ui/views/widget/x11_desktop_window_move_client.cc
new file mode 100644
index 0000000000000000000000000000000000000000..70ef3876fd8f9b74ebad624ffc0ad11cd9aa251f
--- /dev/null
+++ b/ui/views/widget/x11_desktop_window_move_client.cc
@@ -0,0 +1,122 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/views/widget/x11_desktop_window_move_client.h"
+
+#include <X11/Xlib.h>
+// Get rid of a macro from Xlib.h that conflicts with Aura's RootWindow class.
+#undef RootWindow
+
+#include "base/message_loop.h"
+#include "base/message_pump_aurax11.h"
+#include "base/run_loop.h"
+#include "ui/aura/env.h"
+#include "ui/aura/root_window.h"
+#include "ui/base/event.h"
+#include "ui/base/x/x11_util.h"
+#include "ui/gfx/screen.h"
+
+namespace views {
+
+X11DesktopWindowMoveClient::X11DesktopWindowMoveClient()
+    : in_move_loop_(false) {
+}
+
+X11DesktopWindowMoveClient::~X11DesktopWindowMoveClient() {}
+
+bool X11DesktopWindowMoveClient::PreHandleKeyEvent(aura::Window* target,
+                                                   ui::KeyEvent* event) {
+  return false;
+}
+
+bool X11DesktopWindowMoveClient::PreHandleMouseEvent(aura::Window* target,
+                                                     ui::MouseEvent* event) {
+  if (in_move_loop_) {
+    switch (event->type()) {
+      case ui::ET_MOUSE_DRAGGED:
+      case ui::ET_MOUSE_MOVED: {
+        DCHECK(event->valid_system_location());
+        gfx::Point system_loc =
+            event->system_location().Subtract(window_offset_);
+        aura::RootWindow* root_window = target->GetRootWindow();
+        root_window->SetHostBounds(gfx::Rect(
+            system_loc, root_window->GetHostSize()));
+        return true;
+      }
+      case ui::ET_MOUSE_CAPTURE_CHANGED:
+      case ui::ET_MOUSE_RELEASED: {
+        EndMoveLoop();
+        return true;
+      }
+      default:
+        break;
+    }
+  }
+
+  return false;
+}
+
+ui::TouchStatus X11DesktopWindowMoveClient::PreHandleTouchEvent(
+    aura::Window* target,
+    ui::TouchEvent* event) {
+  return ui::TOUCH_STATUS_UNKNOWN;
+}
+
+ui::GestureStatus X11DesktopWindowMoveClient::PreHandleGestureEvent(
+    aura::Window* target,
+    ui::GestureEvent* event) {
+  return ui::GESTURE_STATUS_UNKNOWN;
+}
+
+void X11DesktopWindowMoveClient::RunMoveLoop(aura::Window* source,
+                                             const gfx::Point& drag_offset) {
+  DCHECK(!in_move_loop_);  // Can only handle one nested loop at a time.
+  in_move_loop_ = true;
+  window_offset_ = drag_offset;
+
+  source->GetRootWindow()->ShowRootWindow();
+
+  Display* display = base::MessagePumpAuraX11::GetDefaultXDisplay();
+  XGrabServer(display);
+  XUngrabPointer(display, CurrentTime);
+
+  aura::RootWindow* root_window = source->GetRootWindow();
+  int ret = XGrabPointer(display,
+                         root_window->GetAcceleratedWidget(),
+                         False,
+                         ButtonReleaseMask | PointerMotionMask,
+                         GrabModeAsync,
+                         GrabModeAsync,
+                         None,
+                         None,
+                         CurrentTime);
+  if (ret != GrabSuccess) {
+    NOTREACHED() << "Grab failed: " << ret;
+  }
+  XUngrabServer(display);
+
+  MessageLoopForUI* loop = MessageLoopForUI::current();
+  MessageLoop::ScopedNestableTaskAllower allow_nested(loop);
+  base::RunLoop run_loop(aura::Env::GetInstance()->GetDispatcher());
+  quit_closure_ = run_loop.QuitClosure();
+  run_loop.Run();
+}
+
+void X11DesktopWindowMoveClient::EndMoveLoop() {
+  if (!in_move_loop_)
+    return;
+
+  // TODO(erg): Is this ungrab the cause of having to click to give input focus
+  // on drawn out windows? Not ungrabing here screws the X server until I kill
+  // the chrome process.
+
+  // Ungrab before we let go of the window.
+  Display* display = base::MessagePumpAuraX11::GetDefaultXDisplay();
+  XUngrabPointer(display, CurrentTime);
+
+  in_move_loop_ = false;
+  quit_closure_.Run();
+}
+
+}  // namespace views