AppShell: Create input method and handle key events

extensions/shell/browser/shell_desktop_controller_aura.cc

 // Copyright 2014 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 "extensions/shell/browser/shell_desktop_controller_aura.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
 #include "extensions/browser/app_window/app_window.h"
 #include "extensions/browser/app_window/native_app_window.h"
+#include "extensions/shell/browser/input_method_event_handler.h"
 #include "extensions/shell/browser/shell_app_delegate.h"
 #include "extensions/shell/browser/shell_app_window_client.h"
 #include "extensions/shell/browser/shell_screen.h"
 #include "extensions/shell/common/switches.h"
 #include "ui/aura/client/cursor_client.h"
 #include "ui/aura/client/default_capture_client.h"
 #include "ui/aura/layout_manager.h"
 #include "ui/aura/window.h"
-#include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_tree_host.h"
 #include "ui/base/cursor/cursor.h"
 #include "ui/base/cursor/image_cursors.h"
-#include "ui/base/ime/input_method_initializer.h"
+#include "ui/base/ime/input_method.h"
 #include "ui/base/user_activity/user_activity_detector.h"
 #include "ui/display/screen.h"
+#include "ui/events/event_processor.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/wm/core/base_focus_rules.h"
 #include "ui/wm/core/compound_event_filter.h"
 #include "ui/wm/core/cursor_manager.h"
 #include "ui/wm/core/focus_controller.h"
 #include "ui/wm/core/native_cursor_manager.h"
 #include "ui/wm/core/native_cursor_manager_delegate.h"
 
 #if defined(OS_CHROMEOS)
@@ skipping 220 matching lines @@
 #endif
 
 void ShellDesktopControllerAura::OnHostCloseRequested(
     const aura::WindowTreeHost* host) {
   DCHECK_EQ(host_.get(), host);
   CloseAppWindows();
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
 }
 
+ui::EventDispatchDetails ShellDesktopControllerAura::DispatchKeyEventPostIME(
+    ui::KeyEvent* key_event) {
+  // The input method has processed this event, so prevent the handler from
+  // dispatching it again.
+  input_method_event_handler_->set_post_ime(true);
+
+  // Send the event on to the host.
+  ui::EventDispatchDetails details =
+      host_->event_processor()->OnEventFromSource(key_event);
+
+  // Clear the handler's PostIME flag for the next event.
+  if (!details.dispatcher_destroyed)
+    input_method_event_handler_->set_post_ime(false);
+
+  return details;
+}
+
 void ShellDesktopControllerAura::InitWindowManager() {
   wm::FocusController* focus_controller =
       new wm::FocusController(new AppsFocusRules());
   aura::client::SetFocusClient(host_->window(), focus_controller);
   host_->window()->AddPreTargetHandler(focus_controller);
   aura::client::SetActivationClient(host_->window(), focus_controller);
   focus_client_.reset(focus_controller);
 
   capture_client_.reset(
       new aura::client::DefaultCaptureClient(host_->window()));
@@ skipping 27 matching lines @@
     CHECK_EQ(2, sscanf(size_str.c_str(), "%dx%d", &width, &height));
     size = gfx::Size(width, height);
   } else {
     size = GetPrimaryDisplaySize();
   }
   if (size.IsEmpty())
     size = gfx::Size(1920, 1080);
 
   screen_.reset(new ShellScreen(size));
   display::Screen::SetScreenInstance(screen_.get());
-  // TODO(mukai): Set up input method.
 
   host_.reset(screen_->CreateHostForPrimaryDisplay());
   aura::client::SetWindowParentingClient(host_->window(), this);
   root_window_event_filter_.reset(new wm::CompoundEventFilter);
   host_->window()->AddPreTargetHandler(root_window_event_filter_.get());
+
+  // Trigger creation of an input method and become its delegate.
+  ui::InputMethod* input_method = host_->GetInputMethod();
+  input_method->SetDelegate(this);
+  input_method_event_handler_.reset(new InputMethodEventHandler(input_method));
+  host_->window()->AddPreTargetHandler(input_method_event_handler_.get());
+
   InitWindowManager();
 
   host_->AddObserver(this);
 
   // Ensure the X window gets mapped.
   host_->Show();
 }
 
 void ShellDesktopControllerAura::DestroyRootWindow() {
   host_->RemoveObserver(this);
   wm::FocusController* focus_controller =
       static_cast<wm::FocusController*>(focus_client_.get());
   if (focus_controller) {
     host_->window()->RemovePreTargetHandler(focus_controller);
     aura::client::SetActivationClient(host_->window(), NULL);
   }
+
+  host_->window()->RemovePreTargetHandler(input_method_event_handler_.get());
+  input_method_event_handler_.reset();
+
+  host_->window()->RemovePreTargetHandler(root_window_event_filter_.get());
   root_window_event_filter_.reset();
+
   capture_client_.reset();
   focus_client_.reset();
   cursor_manager_.reset();
 #if defined(OS_CHROMEOS)
   user_activity_notifier_.reset();
 #endif
   user_activity_detector_.reset();
   host_.reset();
   screen_.reset();
+  display::Screen::SetScreenInstance(nullptr);

[James Cook, 2016/12/17 18:24:41]

nit: do this before screen_.reset() -- if someone adds side effects to the
screen destructor you probably don't want to allow it to reach into the
singleton instance

Also, I suggest adding a comment somewhere that app_shell only supports a single
screen/display. (I'm pretty sure that's true -- it looks like there's only one
ShellDesktopController, so one screen_.)

[michaelpg, 2016/12/18 01:46:10]

Done.

 }
 
 gfx::Size ShellDesktopControllerAura::GetPrimaryDisplaySize() {
 #if defined(OS_CHROMEOS)
   const ui::DisplayConfigurator::DisplayStateList& displays =
       display_configurator_->cached_displays();
   if (displays.empty())
     return gfx::Size();
   const ui::DisplayMode* mode = displays[0]->current_mode();
   return mode ? mode->size() : gfx::Size();
 #else
   return gfx::Size();
 #endif
 }
 
 }  // namespace extensions