root/chrome/browser/ui/views/panels/panel_stack_view.cc

DEFINITIONS

1. delegate_
2. GetWindowTitle
3. GetWindowAppIcon
4. GetWindowIcon
5. GetWidget
6. GetWidget
7. OnWidgetClosing
8. OnWidgetDestroying
9. Create
10. bounds_updates_started_
11. Close
12. AddPanel
13. RemovePanel
14. MergeWith
15. IsEmpty
16. HasPanel
17. MovePanelsBy
18. BeginBatchUpdatePanelBounds
19. AddPanelBoundsForBatchUpdate
20. EndBatchUpdatePanelBounds
21. NotifyBoundsUpdateCompleted
22. IsAnimatingPanelBounds
23. Minimize
24. IsMinimized
25. DrawSystemAttention
26. OnPanelActivated
27. OnNativeFocusChange
28. AnimationEnded
29. AnimationCanceled
30. AnimationProgressed
31. UpdatePanelsBounds
32. GetStackWindowBounds
33. UpdateStackWindowBounds
34. MakeStackWindowOwnPanelWindow
35. CreateWindowWithBounds
36. EnsureWindowCreated
37. FilterMessage
38. GetSnapshotWindowHandles
39. RefreshLivePreviewThumbnail
40. DeferUpdateNativeWindowBounds

// 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 "chrome/browser/ui/views/panels/panel_stack_view.h"

#include "base/logging.h"
#include "base/strings/utf_string_conversions.h"
#include "chrome/browser/profiles/profile.h"
#include "chrome/browser/ui/panels/panel.h"
#include "chrome/browser/ui/panels/panel_manager.h"
#include "chrome/browser/ui/panels/stacked_panel_collection.h"
#include "chrome/browser/ui/views/panels/panel_view.h"
#include "ui/gfx/animation/linear_animation.h"
#include "ui/gfx/image/image_skia.h"
#include "ui/gfx/rect.h"
#include "ui/views/widget/widget.h"

#if defined(OS_WIN)
#include "base/win/windows_version.h"
#include "chrome/browser/shell_integration.h"
#include "ui/base/win/shell.h"
#include "ui/views/win/hwnd_util.h"
#endif

namespace {
// These values are experimental and subjective.
const int kDefaultFramerateHz = 50;
const int kSetBoundsAnimationMs = 180;

// The widget window that acts as a background window for the stack of panels.
class PanelStackWindow : public views::WidgetObserver,
                         public views::WidgetDelegateView {
 public:
  PanelStackWindow(const gfx::Rect& bounds,
                   NativePanelStackWindowDelegate* delegate);
  virtual ~PanelStackWindow();

  // Overridden from views::WidgetDelegate:
  virtual base::string16 GetWindowTitle() const OVERRIDE;
  virtual gfx::ImageSkia GetWindowAppIcon() OVERRIDE;
  virtual gfx::ImageSkia GetWindowIcon() OVERRIDE;
  virtual views::Widget* GetWidget() OVERRIDE;
  virtual const views::Widget* GetWidget() const OVERRIDE;

  // Overridden from views::WidgetObserver:
  virtual void OnWidgetClosing(views::Widget* widget) OVERRIDE;
  virtual void OnWidgetDestroying(views::Widget* widget) OVERRIDE;

 private:
  views::Widget* window_;  // Weak pointer, own us.
  NativePanelStackWindowDelegate* delegate_;  // Weak pointer.

  DISALLOW_COPY_AND_ASSIGN(PanelStackWindow);
};

PanelStackWindow::PanelStackWindow(const gfx::Rect& bounds,
                                   NativePanelStackWindowDelegate* delegate)
    : window_(NULL),
      delegate_(delegate) {
  window_ = new views::Widget;
  views::Widget::InitParams params(views::Widget::InitParams::TYPE_WINDOW);
  params.delegate = this;
  params.remove_standard_frame = true;
  params.bounds = bounds;
  window_->Init(params);
  window_->set_frame_type(views::Widget::FRAME_TYPE_FORCE_CUSTOM);
  window_->set_focus_on_creation(false);
  window_->AddObserver(this);
  window_->ShowInactive();
}

PanelStackWindow::~PanelStackWindow() {
}

base::string16 PanelStackWindow::GetWindowTitle() const {
  return delegate_ ? delegate_->GetTitle() : base::string16();
}

gfx::ImageSkia PanelStackWindow::GetWindowAppIcon() {
  if (delegate_) {
    gfx::Image app_icon = delegate_->GetIcon();
    if (!app_icon.IsEmpty())
      return *app_icon.ToImageSkia();
  }
  return gfx::ImageSkia();
}

gfx::ImageSkia PanelStackWindow::GetWindowIcon() {
  return GetWindowAppIcon();
}

views::Widget* PanelStackWindow::GetWidget() {
  return window_;
}

const views::Widget* PanelStackWindow::GetWidget() const {
  return window_;
}

void PanelStackWindow::OnWidgetClosing(views::Widget* widget) {
  delegate_ = NULL;
}

void PanelStackWindow::OnWidgetDestroying(views::Widget* widget) {
  window_ = NULL;
}

}

// static
NativePanelStackWindow* NativePanelStackWindow::Create(
    NativePanelStackWindowDelegate* delegate) {
#if defined(OS_WIN)
  return new PanelStackView(delegate);
#else
  NOTIMPLEMENTED();
  return NULL;
#endif
}

PanelStackView::PanelStackView(NativePanelStackWindowDelegate* delegate)
    : delegate_(delegate),
      window_(NULL),
      is_drawing_attention_(false),
      animate_bounds_updates_(false),
      bounds_updates_started_(false) {
  DCHECK(delegate);
  views::WidgetFocusManager::GetInstance()->AddFocusChangeListener(this);
}

PanelStackView::~PanelStackView() {
#if defined(OS_WIN)
  ui::HWNDSubclass::RemoveFilterFromAllTargets(this);
#endif
}

void PanelStackView::Close() {
  delegate_ = NULL;
  if (bounds_animator_)
    bounds_animator_.reset();
  if (window_)
    window_->Close();
  views::WidgetFocusManager::GetInstance()->RemoveFocusChangeListener(this);
}

void PanelStackView::AddPanel(Panel* panel) {
  panels_.push_back(panel);

  EnsureWindowCreated();
  MakeStackWindowOwnPanelWindow(panel, this);
  UpdateStackWindowBounds();

  window_->UpdateWindowTitle();
  window_->UpdateWindowIcon();
}

void PanelStackView::RemovePanel(Panel* panel) {
  if (IsAnimatingPanelBounds()) {
    // This panel is gone.
    bounds_updates_.erase(panel);

    // Abort the ongoing animation.
    bounds_animator_->Stop();
  }

  panels_.remove(panel);

  MakeStackWindowOwnPanelWindow(panel, NULL);
  UpdateStackWindowBounds();
}

void PanelStackView::MergeWith(NativePanelStackWindow* another) {
  PanelStackView* another_stack = static_cast<PanelStackView*>(another);

  for (Panels::const_iterator iter = another_stack->panels_.begin();
       iter != another_stack->panels_.end(); ++iter) {
    Panel* panel = *iter;
    panels_.push_back(panel);
    MakeStackWindowOwnPanelWindow(panel, this);
  }
  another_stack->panels_.clear();

  UpdateStackWindowBounds();
}

bool PanelStackView::IsEmpty() const {
  return panels_.empty();
}

bool PanelStackView::HasPanel(Panel* panel) const {
  return std::find(panels_.begin(), panels_.end(), panel) != panels_.end();
}

void PanelStackView::MovePanelsBy(const gfx::Vector2d& delta) {
  BeginBatchUpdatePanelBounds(false);
  for (Panels::const_iterator iter = panels_.begin();
       iter != panels_.end(); ++iter) {
    Panel* panel = *iter;
    AddPanelBoundsForBatchUpdate(panel, panel->GetBounds() + delta);
  }
  EndBatchUpdatePanelBounds();
}

void PanelStackView::BeginBatchUpdatePanelBounds(bool animate) {
  // If the batch animation is still in progress, continue the animation
  // with the new target bounds even we want to update the bounds instantly
  // this time.
  if (!bounds_updates_started_) {
    animate_bounds_updates_ = animate;
    bounds_updates_started_ = true;
  }
}

void PanelStackView::AddPanelBoundsForBatchUpdate(Panel* panel,
                                                  const gfx::Rect& new_bounds) {
  DCHECK(bounds_updates_started_);

  // No need to track it if no change is needed.
  if (panel->GetBounds() == new_bounds)
    return;

  // Old bounds are stored as the map value.
  bounds_updates_[panel] = panel->GetBounds();

  // New bounds are directly applied to the valued stored in native panel
  // window.
  static_cast<PanelView*>(panel->native_panel())->set_cached_bounds_directly(
      new_bounds);
}

void PanelStackView::EndBatchUpdatePanelBounds() {
  DCHECK(bounds_updates_started_);

  if (bounds_updates_.empty() || !animate_bounds_updates_) {
    if (!bounds_updates_.empty()) {
      UpdatePanelsBounds();
      bounds_updates_.clear();
    }

    bounds_updates_started_ = false;
    NotifyBoundsUpdateCompleted();
    return;
  }

  bounds_animator_.reset(new gfx::LinearAnimation(
      PanelManager::AdjustTimeInterval(kSetBoundsAnimationMs),
      kDefaultFramerateHz,
      this));
  bounds_animator_->Start();
}

void PanelStackView::NotifyBoundsUpdateCompleted() {
  delegate_->PanelBoundsBatchUpdateCompleted();

#if defined(OS_WIN)
  // Refresh the thumbnail each time when any bounds updates are done.
  RefreshLivePreviewThumbnail();
#endif
}

bool PanelStackView::IsAnimatingPanelBounds() const {
  return bounds_updates_started_ && animate_bounds_updates_;
}

void PanelStackView::Minimize() {
#if defined(OS_WIN)
  // When the stack window is minimized by the system, its snapshot could not
  // be obtained. We need to capture the snapshot before the minimization.
  if (thumbnailer_)
    thumbnailer_->CaptureSnapshot();
#endif

  window_->Minimize();
}

bool PanelStackView::IsMinimized() const {
  return window_ ? window_->IsMinimized() : false;
}

void PanelStackView::DrawSystemAttention(bool draw_attention) {
  // The underlying call of FlashFrame, FlashWindowEx, seems not to work
  // correctly if it is called more than once consecutively.
  if (draw_attention == is_drawing_attention_)
    return;
  is_drawing_attention_ = draw_attention;

#if defined(OS_WIN)
  // Refresh the thumbnail when a panel could change something for the
  // attention.
  RefreshLivePreviewThumbnail();

  if (draw_attention) {
    // The default implementation of Widget::FlashFrame only flashes 5 times.
    // We need more than that.
    FLASHWINFO fwi;
    fwi.cbSize = sizeof(fwi);
    fwi.hwnd = views::HWNDForWidget(window_);
    fwi.dwFlags = FLASHW_ALL;
    fwi.uCount = panel::kNumberOfTimesToFlashPanelForAttention;
    fwi.dwTimeout = 0;
    ::FlashWindowEx(&fwi);
  } else {
    // Calling FlashWindowEx with FLASHW_STOP flag does not always work.
    // Occasionally the taskbar icon could still remain in the flashed state.
    // To work around this problem, we recreate the underlying window.
    views::Widget* old_window = window_;
    window_ = CreateWindowWithBounds(GetStackWindowBounds());

    // New background window should also be minimized if the old one is.
    if (old_window->IsMinimized())
      window_->Minimize();

    // Make sure the new background window stays at the same z-order as the old
    // one.
    ::SetWindowPos(views::HWNDForWidget(window_),
                   views::HWNDForWidget(old_window),
                   0, 0, 0, 0,
                   SWP_NOACTIVATE | SWP_NOMOVE | SWP_NOSIZE);
    for (Panels::const_iterator iter = panels_.begin();
         iter != panels_.end(); ++iter) {
      MakeStackWindowOwnPanelWindow(*iter, this);
    }

    // Serve the snapshot to the new backgroud window.
    if (thumbnailer_.get())
      thumbnailer_->ReplaceWindow(views::HWNDForWidget(window_));

    window_->UpdateWindowTitle();
    window_->UpdateWindowIcon();
    old_window->Close();
  }
#else
  window_->FlashFrame(draw_attention);
#endif
}

void PanelStackView::OnPanelActivated(Panel* panel) {
  // Nothing to do.
}

void PanelStackView::OnNativeFocusChange(gfx::NativeView focused_before,
                                         gfx::NativeView focused_now) {
  // When the user selects the stacked panels via ALT-TAB or WIN-TAB, the
  // background stack window, instead of the foreground panel window, receives
  // WM_SETFOCUS message. To deal with this, we listen to the focus change event
  // and activate the most recently active panel.
  // Note that OnNativeFocusChange might be called when window_ has not be
  // created yet.
#if defined(OS_WIN)
  if (!panels_.empty() && window_ && focused_now == window_->GetNativeView()) {
    Panel* panel_to_focus =
        panels_.front()->stack()->most_recently_active_panel();
    if (panel_to_focus)
      panel_to_focus->Activate();
  }
#endif
}

void PanelStackView::AnimationEnded(const gfx::Animation* animation) {
  bounds_updates_started_ = false;

  PanelManager* panel_manager = PanelManager::GetInstance();
  for (BoundsUpdates::const_iterator iter = bounds_updates_.begin();
       iter != bounds_updates_.end(); ++iter) {
    panel_manager->OnPanelAnimationEnded(iter->first);
  }
  bounds_updates_.clear();

  NotifyBoundsUpdateCompleted();
}

void PanelStackView::AnimationCanceled(const gfx::Animation* animation) {
  // When the animation is aborted due to something like one of panels is gone,
  // update panels to their taget bounds immediately.
  UpdatePanelsBounds();

  AnimationEnded(animation);
}

void PanelStackView::AnimationProgressed(const gfx::Animation* animation) {
  UpdatePanelsBounds();
}

void PanelStackView::UpdatePanelsBounds() {
#if defined(OS_WIN)
  // Add an extra count for the background stack window.
  HDWP defer_update = ::BeginDeferWindowPos(bounds_updates_.size() + 1);
#endif

  // Update the bounds for each panel in the update list.
  gfx::Rect enclosing_bounds;
  for (BoundsUpdates::const_iterator iter = bounds_updates_.begin();
       iter != bounds_updates_.end(); ++iter) {
    Panel* panel = iter->first;
    gfx::Rect target_bounds = panel->GetBounds();
    gfx::Rect current_bounds;
    if (bounds_animator_ && bounds_animator_->is_animating()) {
      current_bounds = bounds_animator_->CurrentValueBetween(
          iter->second, target_bounds);
    } else {
      current_bounds = target_bounds;
    }

    PanelView* panel_view = static_cast<PanelView*>(panel->native_panel());
#if defined(OS_WIN)
    DeferUpdateNativeWindowBounds(defer_update,
                                  panel_view->window(),
                                  current_bounds);
#else
    panel_view->SetPanelBoundsInstantly(current_bounds);
#endif

    enclosing_bounds = UnionRects(enclosing_bounds, current_bounds);
  }

  // Compute the stack window bounds that enclose those panels that are not
  // in the batch update list.
  for (Panels::const_iterator iter = panels_.begin();
       iter != panels_.end(); ++iter) {
    Panel* panel = *iter;
    if (bounds_updates_.find(panel) == bounds_updates_.end())
      enclosing_bounds = UnionRects(enclosing_bounds, panel->GetBounds());
  }

  // Update the bounds of the background stack window.
#if defined(OS_WIN)
  DeferUpdateNativeWindowBounds(defer_update, window_, enclosing_bounds);
#else
  window_->SetBounds(enclosing_bounds);
#endif

#if defined(OS_WIN)
  ::EndDeferWindowPos(defer_update);
#endif
}

gfx::Rect PanelStackView::GetStackWindowBounds() const {
  gfx::Rect enclosing_bounds;
  for (Panels::const_iterator iter = panels_.begin();
       iter != panels_.end(); ++iter) {
    Panel* panel = *iter;
    enclosing_bounds = UnionRects(enclosing_bounds, panel->GetBounds());
  }
  return enclosing_bounds;
}

void PanelStackView::UpdateStackWindowBounds() {
  window_->SetBounds(GetStackWindowBounds());

#if defined(OS_WIN)
  // Refresh the thumbnail each time whne the stack window is changed, due to
  // adding or removing a panel.
  RefreshLivePreviewThumbnail();
#endif
}

// static
void PanelStackView::MakeStackWindowOwnPanelWindow(
    Panel* panel, PanelStackView* stack_window) {
#if defined(OS_WIN)
  // The panel widget window might already be gone when a panel is closed.
  views::Widget* panel_window =
      static_cast<PanelView*>(panel->native_panel())->window();
  if (!panel_window)
    return;

  HWND native_panel_window = views::HWNDForWidget(panel_window);
  HWND native_stack_window =
      stack_window ? views::HWNDForWidget(stack_window->window_) : NULL;

  // The extended style WS_EX_APPWINDOW is used to force a top-level window onto
  // the taskbar. In order for multiple stacked panels to appear as one, this
  // bit needs to be cleared.
  int value = ::GetWindowLong(native_panel_window, GWL_EXSTYLE);
  ::SetWindowLong(
      native_panel_window,
      GWL_EXSTYLE,
      native_stack_window ? (value & ~WS_EX_APPWINDOW)
                          : (value | WS_EX_APPWINDOW));

  // All the windows that share the same owner window will appear as a single
  // window on the taskbar.
  ::SetWindowLongPtr(native_panel_window,
                     GWLP_HWNDPARENT,
                     reinterpret_cast<LONG_PTR>(native_stack_window));

  // Make sure the background stack window always stays behind the panel window.
  if (native_stack_window) {
    ::SetWindowPos(native_stack_window, native_panel_window, 0, 0, 0, 0,
        SWP_NOACTIVATE | SWP_NOMOVE | SWP_NOSIZE);
  }

#else
  NOTIMPLEMENTED();
#endif
}

views::Widget* PanelStackView::CreateWindowWithBounds(const gfx::Rect& bounds) {
  PanelStackWindow* stack_window = new PanelStackWindow(bounds, delegate_);
  views::Widget* window = stack_window->GetWidget();

#if defined(OS_WIN)
  DCHECK(!panels_.empty());
  Panel* panel = panels_.front();
  ui::win::SetAppIdForWindow(
      ShellIntegration::GetAppModelIdForProfile(
          base::UTF8ToWide(panel->app_name()), panel->profile()->GetPath()),
      views::HWNDForWidget(window));

  // Remove the filter for old window in case that we're recreating the window.
  ui::HWNDSubclass::RemoveFilterFromAllTargets(this);

  // Listen to WM_MOVING message in order to move all panels windows on top of
  // the background window altogether when the background window is being moved
  // by the user.
  ui::HWNDSubclass::AddFilterToTarget(views::HWNDForWidget(window), this);
#endif

  return window;
}

void PanelStackView::EnsureWindowCreated() {
  if (window_)
    return;

  // Empty size is not allowed so a temporary small size is passed. SetBounds
  // will be called later to update the bounds.
  window_ = CreateWindowWithBounds(gfx::Rect(0, 0, 1, 1));

#if defined(OS_WIN)
  if (base::win::GetVersion() >= base::win::VERSION_WIN7) {
    HWND native_window = views::HWNDForWidget(window_);
    thumbnailer_.reset(new TaskbarWindowThumbnailerWin(native_window, this));
    thumbnailer_->Start();
  }
#endif
}

#if defined(OS_WIN)
bool PanelStackView::FilterMessage(HWND hwnd,
                                   UINT message,
                                   WPARAM w_param,
                                   LPARAM l_param,
                                   LRESULT* l_result) {
  switch (message) {
    case WM_MOVING:
      // When the background window is being moved by the user, all panels
      // should also move.
      gfx::Rect new_stack_bounds(*(reinterpret_cast<LPRECT>(l_param)));
      MovePanelsBy(
          new_stack_bounds.origin() - panels_.front()->GetBounds().origin());
      break;
  }
  return false;
}

std::vector<HWND> PanelStackView::GetSnapshotWindowHandles() const {
  std::vector<HWND> native_panel_windows;
  for (Panels::const_iterator iter = panels_.begin();
       iter != panels_.end(); ++iter) {
    Panel* panel = *iter;
    native_panel_windows.push_back(
        views::HWNDForWidget(
            static_cast<PanelView*>(panel->native_panel())->window()));
  }
  return native_panel_windows;
}

void PanelStackView::RefreshLivePreviewThumbnail() {
  // Don't refresh the thumbnail when the stack window is system minimized
  // because the snapshot could not be retrieved.
  if (!thumbnailer_.get() || IsMinimized())
    return;
  thumbnailer_->InvalidateSnapshot();
}

void PanelStackView::DeferUpdateNativeWindowBounds(HDWP defer_window_pos_info,
                                                   views::Widget* window,
                                                   const gfx::Rect& bounds) {
  ::DeferWindowPos(defer_window_pos_info,
                    views::HWNDForWidget(window),
                    NULL,
                    bounds.x(),
                    bounds.y(),
                    bounds.width(),
                    bounds.height(),
                    SWP_NOACTIVATE | SWP_NOZORDER);
}
#endif