Show ChromeVox caption panel when spoken feedback is enabled.

chrome/browser/chromeos/accessibility/chromevox_panel.cc

+// Copyright 2015 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 "ash/shell.h"
+#include "ash/shell_window_ids.h"
+#include "chrome/browser/chromeos/accessibility/accessibility_manager.h"
+#include "chrome/browser/chromeos/accessibility/chromevox_panel.h"
+#include "chrome/common/extensions/extension_constants.h"
+#include "content/public/browser/web_contents.h"
+#include "ui/chromeos/accessibility_types.h"
+#include "ui/views/controls/webview/webview.h"
+#include "ui/views/layout/fill_layout.h"
+#include "ui/views/widget/widget.h"
+#include "ui/wm/core/shadow_types.h"
+#include "ui/wm/core/window_animations.h"
+
+namespace {
+
+const int kPanelHeight = 35;
+const char kChromeVoxPanelRelativeUrl[] = "/cvox2/background/panel.html";
+const char kFullscreenURLFragment[] = "fullscreen";
+const char kDisableSpokenFeedbackURLFragment[] = "close";
+
+}  // namespace
+
+class ChromeVoxPanelWebContentsObserver : public content::WebContentsObserver {
+ public:
+  ChromeVoxPanelWebContentsObserver(content::WebContents* web_contents,
+                                    ChromeVoxPanel* panel)
+      : content::WebContentsObserver(web_contents), panel_(panel) {}
+  ~ChromeVoxPanelWebContentsObserver() override {}
+
+  // content::WebContentsObserver overrides.
+  void DidFirstVisuallyNonEmptyPaint() override {
+    panel_->DidFirstVisuallyNonEmptyPaint();
+  }
+
+  void DidFinishNavigation(
+      content::NavigationHandle* navigation_handle) override {
+    // The ChromeVox panel uses the URL fragment to communicate state
+    // to this panel host.
+    std::string fragment = web_contents()->GetLastCommittedURL().ref();
+    if (fragment == kDisableSpokenFeedbackURLFragment)
+      panel_->DisableSpokenFeedback();
+    else if (fragment == kFullscreenURLFragment)
+      panel_->EnterFullscreen();
+    else
+      panel_->ExitFullscreen();
+  }
+
+ private:
+  ChromeVoxPanel* panel_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChromeVoxPanelWebContentsObserver);
+};
+
+ChromeVoxPanel::ChromeVoxPanel(content::BrowserContext* browser_context) {
+  std::string url("chrome-extension://");
+  url += extension_misc::kChromeVoxExtensionId;
+  url += kChromeVoxPanelRelativeUrl;
+
+  web_view_ = new views::WebView(browser_context);
+  web_contents_observer_.reset(
+      new ChromeVoxPanelWebContentsObserver(web_view_->GetWebContents(), this));
+  web_view_->LoadInitialURL(GURL(url));
+
+  widget_ = new views::Widget();
+  views::Widget::InitParams params(
+      views::Widget::InitParams::TYPE_WINDOW_FRAMELESS);
+  aura::Window* root_window = ash::Shell::GetPrimaryRootWindow();
+  params.parent = ash::Shell::GetContainer(
+      root_window, ash::kShellWindowId_SettingBubbleContainer);
+  params.delegate = this;
+  params.bounds = gfx::Rect(0, 0, root_window->bounds().width(),
+                            root_window->bounds().height());
+  widget_->Init(params);
+  SetShadowType(widget_->GetNativeWindow(), wm::SHADOW_TYPE_RECTANGULAR);
+
+  ash::Shell::GetScreen()->AddObserver(this);
+}
+
+ChromeVoxPanel::~ChromeVoxPanel() {
+  ash::Shell::GetScreen()->RemoveObserver(this);
+}
+
+int ChromeVoxPanel::GetHeight() {
+  return kPanelHeight;
+}
+
+aura::Window* ChromeVoxPanel::GetRootWindow() {
+  return GetWidget()->GetNativeWindow()->GetRootWindow();
+}
+
+void ChromeVoxPanel::Close() {
+  widget_->Close();
+}
+
+void ChromeVoxPanel::DidFirstVisuallyNonEmptyPaint() {
+  widget_->Show();
+  ash::Shell::GetInstance()->UpdateDisplayWorkAreaInsets(GetRootWindow());
+}
+
+void ChromeVoxPanel::EnterFullscreen() {
+  fullscreen_ = true;
+  UpdateWidgetBounds();
+}
+
+void ChromeVoxPanel::ExitFullscreen() {
+  fullscreen_ = false;
+  UpdateWidgetBounds();
+}
+
+void ChromeVoxPanel::DisableSpokenFeedback() {
+  chromeos::AccessibilityManager::Get()->EnableSpokenFeedback(
+      false, ui::A11Y_NOTIFICATION_NONE);
+}
+
+const views::Widget* ChromeVoxPanel::GetWidget() const {
+  return widget_;
+}
+
+views::Widget* ChromeVoxPanel::GetWidget() {
+  return widget_;
+}
+
+void ChromeVoxPanel::DeleteDelegate() {
+  delete this;
+}
+
+views::View* ChromeVoxPanel::GetContentsView() {
+  return web_view_;

[Jun Mukai, 2015/11/06 18:21:04]

You don't have to remember |web_view_| as an instance variable. You can simply
create it here, and return it.

[dmazzoni, 2015/11/09 23:02:06]

Well, I need the BrowserContext to initialize the web view, so I don't think it
makes any more sense to keep the BrowserContext as an instance variable instead.

I made the instance variable a plan views::View instead. Will that work?

(Also, I know that currently Widget only queries
WidgetDelegate::GetContextView() once on initialization, but this isn't
documented anywhere and it's not at all obvious that it isn't allowed to call it
twice. I glanced through other WidgetDelegates and I couldn't find another
example that creates the view each time it's called.)

+}
+
+void ChromeVoxPanel::OnDisplayMetricsChanged(const gfx::Display& display,
+                                             uint32_t changed_metrics) {
+  UpdateWidgetBounds();
+  ash::Shell::GetInstance()->UpdateDisplayWorkAreaInsets(GetRootWindow());
+}
+
+void ChromeVoxPanel::UpdateWidgetBounds() {
+  gfx::Rect bounds(GetRootWindow()->bounds().size());
+  if (!fullscreen_)
+    bounds.set_height(kPanelHeight);
+  widget_->SetBounds(bounds);
+}