Enable touch based selection and editing for webpages behind a flag.

content/browser/web_contents/touch_editable_impl_aura.cc

+// Copyright (c) 2013 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 "content/browser/web_contents/touch_editable_impl_aura.h"
+
+#include "base/command_line.h"
+#include "content/browser/renderer_host/render_widget_host_impl.h"
+#include "content/browser/renderer_host/render_widget_host_view_aura.h"
+#include "content/common/view_messages.h"
+#include "content/public/browser/render_widget_host.h"
+#include "grit/ui_strings.h"
+#include "ui/aura/client/activation_client.h"
+#include "ui/aura/client/screen_position_client.h"
+#include "ui/aura/root_window.h"
+#include "ui/aura/window.h"
+#include "ui/base/clipboard/clipboard.h"
+#include "ui/base/range/range.h"
+#include "ui/base/ui_base_switches.h"
+
+namespace content {
+
+namespace {
+
+aura::Window* GetToplevelWindowForWindow(aura::Window* window) {
+  aura::RootWindow* root = window->GetRootWindow();
+  if (!root)
+    return NULL;
+  aura::client::ActivationClient* activation_client =
+      aura::client::GetActivationClient(root);
+  if (!activation_client)
+    return NULL;
+  return activation_client->GetToplevelWindow(window);
+}
+
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// TouchEditableImplAura, public:
+
+TouchEditableImplAura::~TouchEditableImplAura() {
+  Cleanup();
+}
+
+// static
+TouchEditableImplAura* TouchEditableImplAura::Create() {
+#if defined(OS_CHROMEOS)
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kEnableTouchEditing))
+    return new TouchEditableImplAura();
+#endif
+  return NULL;
+}
+
+void TouchEditableImplAura::AttachToView(RenderWidgetHostViewAura* view) {
+  if (rwhva_ == view)
+    return;
+
+  Cleanup();
+  if (!view)
+    return;
+
+  rwhva_ = view;
+  rwhva_->set_touch_editing_client(this);
+  aura::Window* window = rwhva_->GetNativeView();
+  window->AddObserver(this);
+  top_level_window_ = GetToplevelWindowForWindow(window);
+  if (top_level_window_)
+    top_level_window_->AddObserver(this);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// TouchEditableImplAura, RenderWidgetHostViewAura::TouchEditingClient
+// implementation:
+
+void TouchEditableImplAura::StartTouchEditing() {
+  if (!touch_selection_controller_) {
+    touch_selection_controller_.reset(
+        ui::TouchSelectionController::create(this));
+  }
+  if (touch_selection_controller_)
+    touch_selection_controller_->SelectionChanged();
+}
+
+void TouchEditableImplAura::EndTouchEditing() {
+  if (touch_selection_controller_) {
+    if (touch_selection_controller_->IsHandleDragInProgress())
+      touch_selection_controller_->SelectionChanged();
+    else
+      touch_selection_controller_.reset();
+  }
+}
+
+void TouchEditableImplAura::OnSelectionOrCursorChanged(const gfx::Rect& anchor,
+                                                       const gfx::Rect& focus) {
+  selection_anchor_rect_ = anchor;
+  selection_focus_rect_ = focus;
+  UpdateController();
+}
+
+void TouchEditableImplAura::OnTextInputTypeChanged(ui::TextInputType type) {
+  text_input_type_ = type;
+}
+
+bool TouchEditableImplAura::HandleInputEvent(const ui::Event* event) {
+  DCHECK(rwhva_);
+  if (event->IsTouchEvent())
+    return false;
+
+  if (!event->IsGestureEvent()) {
+    EndTouchEditing();
+    return false;
+  }
+
+  const ui::GestureEvent* gesture_event =
+      static_cast<const ui::GestureEvent*>(event);
+  switch (event->type()) {
+    case ui::ET_GESTURE_TAP:
+      if (gesture_event->details().tap_count() > 1)
+        selection_gesture_in_process_ = true;
+      // When the user taps, we want to show touch editing handles if user
+      // tapped on selected text.
+      if (selection_anchor_rect_ != selection_focus_rect_) {
+        // UnionRects only works for rects with non-zero width.
+        gfx::Rect anchor(selection_anchor_rect_.origin(),
+                         gfx::Size(1, selection_anchor_rect_.height()));
+        gfx::Rect focus(selection_focus_rect_.origin(),
+                        gfx::Size(1, selection_focus_rect_.height()));
+        gfx::Rect selection_rect = gfx::UnionRects(anchor, focus);
+        if (selection_rect.Contains(gesture_event->location())) {
+          StartTouchEditing();
+          return true;
+        }
+      }
+      break;
+    case ui::ET_GESTURE_LONG_PRESS:
+      selection_gesture_in_process_ = true;
+      break;
+    default:
+      break;
+  }
+  return false;
+}
+
+void TouchEditableImplAura::GestureEventAck(int gesture_event_type) {
+  DCHECK(rwhva_);
+  if (gesture_event_type == WebKit::WebInputEvent::GestureTap &&
+      text_input_type_ != ui::TEXT_INPUT_TYPE_NONE) {
+    StartTouchEditing();
+    if (touch_selection_controller_)
+      touch_selection_controller_->SelectionChanged();
+  }
+
+  if (gesture_event_type == WebKit::WebInputEvent::GestureLongPress ||
+      gesture_event_type == WebKit::WebInputEvent::GestureTap)
+    selection_gesture_in_process_ = false;
+}
+
+void TouchEditableImplAura::OnViewDestroyed() {
+  Cleanup();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// TouchEditableImplAura, ui::TouchEditable implementation:
+
+void TouchEditableImplAura::SelectRect(const gfx::Point& start,
+                                       const gfx::Point& end) {
+  if (!rwhva_)
+    return;
+
+  RenderWidgetHostImpl* host = RenderWidgetHostImpl::From(
+      rwhva_->GetRenderWidgetHost());
+  host->SelectRange(start, end);
+}
+
+void TouchEditableImplAura::MoveCaretTo(const gfx::Point& point) {
+  if (!rwhva_)
+    return;
+
+  RenderWidgetHostImpl* host = RenderWidgetHostImpl::From(
+      rwhva_->GetRenderWidgetHost());
+  host->MoveCaret(point);
+}
+
+void TouchEditableImplAura::GetSelectionEndPoints(gfx::Rect* p1,
+                                                  gfx::Rect* p2) {
+  *p1 = selection_anchor_rect_;
+  *p2 = selection_focus_rect_;
+}
+
+gfx::Rect TouchEditableImplAura::GetBounds() {
+  return rwhva_ ? rwhva_->GetNativeView()->bounds() : gfx::Rect();
+}
+
+gfx::NativeView TouchEditableImplAura::GetNativeView() {
+  return rwhva_ ? rwhva_->GetNativeView()->GetRootWindow() : NULL;
+}
+
+void TouchEditableImplAura::ConvertPointToScreen(gfx::Point* point) {
+  if (!rwhva_)
+    return;
+  aura::Window* window = rwhva_->GetNativeView();
+  aura::client::ScreenPositionClient* screen_position_client =
+      aura::client::GetScreenPositionClient(window->GetRootWindow());
+  if (screen_position_client)
+    screen_position_client->ConvertPointToScreen(window, point);
+}
+
+void TouchEditableImplAura::ConvertPointFromScreen(gfx::Point* point) {
+  if (!rwhva_)
+    return;
+  aura::Window* window = rwhva_->GetNativeView();
+  aura::client::ScreenPositionClient* screen_position_client =
+      aura::client::GetScreenPositionClient(window->GetRootWindow());
+  if (screen_position_client)
+    screen_position_client->ConvertPointFromScreen(window, point);
+}
+
+bool TouchEditableImplAura::DrawsHandles() {
+  return false;
+}
+
+void TouchEditableImplAura::OpenContextMenu(const gfx::Point anchor) {
+  if (!rwhva_)
+    return;
+  RenderWidgetHost* host = rwhva_->GetRenderWidgetHost();
+  host->Send(new ViewMsg_ShowContextMenu(host->GetRoutingID()));
+  EndTouchEditing();
+}
+
+bool TouchEditableImplAura::IsCommandIdChecked(int command_id) const {
+  NOTREACHED();
+  return false;
+}
+
+bool TouchEditableImplAura::IsCommandIdEnabled(int command_id) const {
+  if (!rwhva_)
+    return false;
+  bool editable = rwhva_->GetTextInputType() != ui::TEXT_INPUT_TYPE_NONE;
+  ui::Range selection_range;
+  rwhva_->GetSelectionRange(&selection_range);
+  bool has_selection = !selection_range.is_empty();
+  switch (command_id) {
+    case IDS_APP_CUT:
+      return editable && has_selection;
+    case IDS_APP_COPY:
+      return has_selection;
+    case IDS_APP_PASTE: {
+      string16 result;
+      ui::Clipboard::GetForCurrentThread()->ReadText(
+          ui::Clipboard::BUFFER_STANDARD, &result);
+      return editable && !result.empty();
+    }
+    case IDS_APP_DELETE:
+      return editable && has_selection;
+    case IDS_APP_SELECT_ALL:
+      return true;
+    default:
+      return false;
+  }
+}
+
+bool TouchEditableImplAura::GetAcceleratorForCommandId(
+    int command_id,
+    ui::Accelerator* accelerator) {
+  return false;
+}
+
+void TouchEditableImplAura::ExecuteCommand(int command_id, int event_flags) {
+  if (!rwhva_)
+    return;
+  RenderWidgetHost* host = rwhva_->GetRenderWidgetHost();
+  switch (command_id) {
+    case IDS_APP_CUT:
+      host->Cut();
+      break;
+    case IDS_APP_COPY:
+      host->Copy();
+      break;
+    case IDS_APP_PASTE:
+      host->Paste();
+      break;
+    case IDS_APP_DELETE:
+      host->Delete();
+      break;
+    case IDS_APP_SELECT_ALL:
+      host->SelectAll();
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
+  EndTouchEditing();
+}
+
+void TouchEditableImplAura::OnWindowParentChanged(aura::Window* window,
+                                                  aura::Window* parent) {

[piman, 2013/04/18 22:28:42]

I don't think this is enough. This only tells you if the direct parent changed,
not any parent all the way to the root. So you will not be correctly updating
top_level_window_ if, say, your parent's parent gets changed.

[varunjain, 2013/04/19 05:14:12]

removed top_level_window_

+  if (window == rwhva_->GetNativeView()) {
+    if (top_level_window_)
+      top_level_window_->RemoveObserver(this);
+
+    top_level_window_ = GetToplevelWindowForWindow(window);
+    if (top_level_window_)
+      top_level_window_->AddObserver(this);
+  }
+}
+
+void TouchEditableImplAura::OnWindowBoundsChanged(aura::Window* window,
+                                                  const gfx::Rect& old_bounds,
+                                                  const gfx::Rect& new_bounds) {
+  if (top_level_window_ == window && touch_selection_controller_)
+    touch_selection_controller_->SelectionChanged();

[piman, 2013/04/18 22:28:42]

I don't understand why this is needed, and furthermore, why it's done that way?
Why is the fact that the top-level window changed size impact the selection?
It seems to me this bakes an assumption about UI-level behavior down into
content/, which is a layering violation.

[varunjain, 2013/04/19 05:14:12]

You are correct. This should not be needed here. Removed top_level_window_ and
all associated logic.

+}
+
+void TouchEditableImplAura::OnWindowDestroying(aura::Window* window) {
+  if (top_level_window_ == window) {
+    top_level_window_->RemoveObserver(this);
+    top_level_window_ = NULL;
+  } else if (rwhva_->GetNativeView() == window) {
+    rwhva_->GetNativeView()->RemoveObserver(this);
+  }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// TouchEditableImplAura, private:
+
+TouchEditableImplAura::TouchEditableImplAura()
+    : text_input_type_(ui::TEXT_INPUT_TYPE_NONE),
+      rwhva_(NULL),
+      top_level_window_(NULL),
+      selection_gesture_in_process_(false) {
+}
+
+void TouchEditableImplAura::UpdateController() {
+  DCHECK(rwhva_);
+
+  // If touch editing handles were not visible, we bring them up only if
+  // there is non-zero selection on the page. And the current event is a
+  // gesture event (we dont want to show handles if the user is selecting
+  // using mouse or keyboard).
+  if (selection_gesture_in_process_ &&
+      selection_anchor_rect_ != selection_focus_rect_)
+    StartTouchEditing();
+
+  if (text_input_type_ != ui::TEXT_INPUT_TYPE_NONE ||
+      selection_anchor_rect_ != selection_focus_rect_) {
+    if (touch_selection_controller_)
+      touch_selection_controller_->SelectionChanged();
+  } else
+    EndTouchEditing();
+}
+
+void TouchEditableImplAura::Cleanup() {
+  if (top_level_window_)
+    top_level_window_->RemoveObserver(this);
+  if (rwhva_) {
+    if (rwhva_->GetNativeView())
+      rwhva_->GetNativeView()->RemoveObserver(this);
+    rwhva_->set_touch_editing_client(NULL);
+    rwhva_ = NULL;
+  }
+  touch_selection_controller_.reset();
+}
+
+}  // namespace content