root/ui/views/controls/native/native_view_host.cc

DEFINITIONS

1. focus_view_
2. Attach
3. Detach
4. SetPreferredSize
5. NativeViewDestroyed
6. GetPreferredSize
7. Layout
8. OnPaint
9. VisibilityChanged
10. NeedsNotificationWhenVisibleBoundsChange
11. OnVisibleBoundsChanged
12. ViewHierarchyChanged
13. GetClassName
14. OnFocus
15. GetNativeViewAccessible
16. GetCursor
17. Detach
18. ClearFocus

// 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/controls/native/native_view_host.h"

#include "base/logging.h"
#include "ui/base/cursor/cursor.h"
#include "ui/gfx/canvas.h"
#include "ui/views/accessibility/native_view_accessibility.h"
#include "ui/views/controls/native/native_view_host_wrapper.h"
#include "ui/views/widget/widget.h"

namespace views {

// static
const char NativeViewHost::kViewClassName[] = "NativeViewHost";
const char kWidgetNativeViewHostKey[] = "WidgetNativeViewHost";

// Views implementation draws the focus.
// TODO(oshima): Eliminate this flag and consolidate
// the focus border code.
const bool NativeViewHost::kRenderNativeControlFocus = false;

////////////////////////////////////////////////////////////////////////////////
// NativeViewHost, public:

NativeViewHost::NativeViewHost()
    : native_view_(NULL),
      fast_resize_(false),
      fast_resize_at_last_layout_(false),
      focus_view_(NULL) {
}

NativeViewHost::~NativeViewHost() {
}

void NativeViewHost::Attach(gfx::NativeView native_view) {
  DCHECK(native_view);
  DCHECK(!native_view_);
  native_view_ = native_view;
  // If set_focus_view() has not been invoked, this view is the one that should
  // be seen as focused when the native view receives focus.
  if (!focus_view_)
    focus_view_ = this;
  native_wrapper_->NativeViewWillAttach();
  Widget::ReparentNativeView(native_view_, GetWidget()->GetNativeView());
  Layout();

  Widget* widget = Widget::GetWidgetForNativeView(native_view);
  if (widget)
    widget->SetNativeWindowProperty(kWidgetNativeViewHostKey, this);
}

void NativeViewHost::Detach() {
  Detach(false);
}

void NativeViewHost::SetPreferredSize(const gfx::Size& size) {
  preferred_size_ = size;
  PreferredSizeChanged();
}

void NativeViewHost::NativeViewDestroyed() {
  // Detach so we can clear our state and notify the native_wrapper_ to release
  // ref on the native view.
  Detach(true);
}

////////////////////////////////////////////////////////////////////////////////
// NativeViewHost, View overrides:

gfx::Size NativeViewHost::GetPreferredSize() {
  return preferred_size_;
}

void NativeViewHost::Layout() {
  if (!native_view_ || !native_wrapper_.get())
    return;

  gfx::Rect vis_bounds = GetVisibleBounds();
  bool visible = !vis_bounds.IsEmpty();

  if (visible && !fast_resize_) {
    if (vis_bounds.size() != size()) {
      // Only a portion of the Widget is really visible.
      int x = vis_bounds.x();
      int y = vis_bounds.y();
      native_wrapper_->InstallClip(x, y, vis_bounds.width(),
                                   vis_bounds.height());
    } else if (native_wrapper_->HasInstalledClip()) {
      // The whole widget is visible but we installed a clip on the widget,
      // uninstall it.
      native_wrapper_->UninstallClip();
    }
  }

  if (visible) {
    // Since widgets know nothing about the View hierarchy (they are direct
    // children of the Widget that hosts our View hierarchy) they need to be
    // positioned in the coordinate system of the Widget, not the current
    // view.  Also, they should be positioned respecting the border insets
    // of the native view.
    gfx::Rect local_bounds = ConvertRectToWidget(GetContentsBounds());
    native_wrapper_->ShowWidget(local_bounds.x(), local_bounds.y(),
                                local_bounds.width(),
                                local_bounds.height());
  } else {
    native_wrapper_->HideWidget();
  }
  fast_resize_at_last_layout_ = visible && fast_resize_;
}

void NativeViewHost::OnPaint(gfx::Canvas* canvas) {
  // Paint background if there is one. NativeViewHost needs to paint
  // a background when it is hosted in a TabbedPane. For Gtk implementation,
  // NativeTabbedPaneGtk uses a NativeWidgetGtk as page container and because
  // NativeWidgetGtk hook "expose" with its root view's paint, we need to
  // fill the content. Otherwise, the tab page's background is not properly
  // cleared. For Windows case, it appears okay to not paint background because
  // we don't have a container window in-between. However if you want to use
  // customized background, then this becomes necessary.
  OnPaintBackground(canvas);

  // The area behind our window is black, so during a fast resize (where our
  // content doesn't draw over the full size of our native view, and the native
  // view background color doesn't show up), we need to cover that blackness
  // with something so that fast resizes don't result in black flash.
  //
  // It would be nice if this used some approximation of the page's
  // current background color.
  if (native_wrapper_->HasInstalledClip())
    canvas->FillRect(GetLocalBounds(), SK_ColorWHITE);
}

void NativeViewHost::VisibilityChanged(View* starting_from, bool is_visible) {
  Layout();
}

bool NativeViewHost::NeedsNotificationWhenVisibleBoundsChange() const {
  // The native widget is placed relative to the root. As such, we need to
  // know when the position of any ancestor changes, or our visibility relative
  // to other views changed as it'll effect our position relative to the root.
  return true;
}

void NativeViewHost::OnVisibleBoundsChanged() {
  Layout();
}

void NativeViewHost::ViewHierarchyChanged(
    const ViewHierarchyChangedDetails& details) {
  views::Widget* this_widget = GetWidget();

  // A non-NULL |details.move_view| indicates a move operation i.e. |this| is
  // is being reparented.  If the previous and new parents belong to the same
  // widget, don't remove |this| from the widget.  This saves resources from
  // removing from widget and immediately followed by adding to widget; in
  // particular, there wouldn't be spurious visibilitychange events for web
  // contents of |WebView|.
  if (details.move_view && this_widget &&
      details.move_view->GetWidget() == this_widget) {
    return;
  }

  if (details.is_add && this_widget) {
    if (!native_wrapper_.get())
      native_wrapper_.reset(NativeViewHostWrapper::CreateWrapper(this));
    native_wrapper_->AddedToWidget();
  } else if (!details.is_add) {
    native_wrapper_->RemovedFromWidget();
  }
}

const char* NativeViewHost::GetClassName() const {
  return kViewClassName;
}

void NativeViewHost::OnFocus() {
  native_wrapper_->SetFocus();
  NotifyAccessibilityEvent(ui::AX_EVENT_FOCUS, true);
}

gfx::NativeViewAccessible NativeViewHost::GetNativeViewAccessible() {
  if (native_wrapper_.get()) {
    gfx::NativeViewAccessible accessible_view =
        native_wrapper_->GetNativeViewAccessible();
    if (accessible_view)
      return accessible_view;
  }

  return View::GetNativeViewAccessible();
}

gfx::NativeCursor NativeViewHost::GetCursor(const ui::MouseEvent& event) {
  return native_wrapper_->GetCursor(event.x(), event.y());
}

////////////////////////////////////////////////////////////////////////////////
// NativeViewHost, private:

void NativeViewHost::Detach(bool destroyed) {
  if (native_view_) {
    if (!destroyed) {
      Widget* widget = Widget::GetWidgetForNativeView(native_view_);
      if (widget)
        widget->SetNativeWindowProperty(kWidgetNativeViewHostKey, NULL);
      ClearFocus();
    }
    native_wrapper_->NativeViewDetaching(destroyed);
    native_view_ = NULL;
  }
}

void NativeViewHost::ClearFocus() {
  FocusManager* focus_manager = GetFocusManager();
  if (!focus_manager || !focus_manager->GetFocusedView())
    return;

  Widget::Widgets widgets;
  Widget::GetAllChildWidgets(native_view(), &widgets);
  for (Widget::Widgets::iterator i = widgets.begin(); i != widgets.end(); ++i) {
    focus_manager->ViewRemoved((*i)->GetRootView());
    if (!focus_manager->GetFocusedView())
      return;
  }
}

}  // namespace views