ash: Animate changes in the uber tray.

ash/system/tray/tray_item_view.cc

+// 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 "ash/system/tray/tray_item_view.h"
+
+#include "ui/base/animation/slide_animation.h"
+#include "ui/gfx/compositor/layer.h"
+#include "ui/views/controls/image_view.h"
+#include "ui/views/controls/label.h"
+#include "ui/views/layout/fill_layout.h"
+#include "ui/views/widget/widget.h"
+
+namespace {
+const int kTrayIconHeight = 29;
+const int kTrayItemAnimationDurationMS = 200;
+}
+
+namespace ash {
+namespace internal {
+
+TrayItemView::TrayItemView()
+    : label_(NULL),
+      image_view_(NULL) {
+  SetPaintToLayer(true);
+  SetFillsBoundsOpaquely(false);
+  SetLayoutManager(new views::FillLayout);
+}
+
+TrayItemView::~TrayItemView() {}
+
+void TrayItemView::CreateLabel() {
+  label_ = new views::Label;
+  AddChildView(label_);
+}
+
+void TrayItemView::CreateImageView() {
+  image_view_ = new views::ImageView;
+  AddChildView(image_view_);
+}
+
+void TrayItemView::SetVisible(bool set_visible) {
+  if (!GetWidget()) {

[Ben Goodger (Google), 2012/04/23 15:33:42]

Can you implement this by overriding VisibilityChanged instead of overriding
SetVisible?

[sadrul, 2012/04/23 16:07:58]

This would work when showing the view, however, when hiding, we need to make
sure the view keeps painting while the view is being hidden, so we need to delay
the call to View::SetVisible because that would destroy the layer. So, we make
sure we start the animation here, and defer the View::SetVisible(false) until
the animation ends. (something like a View::AcquireLayer would probably have
been useful here to avoid delaying the call to View::SetVisible)

[Ben Goodger (Google), 2012/04/23 17:43:38]

Ah. I guess we have better support for this sort of thing in Aura. I guess this
can do for now. I'd like to come up with a better strategy for this in the long
run, but I'll take the AI to do that.

+    views::View::SetVisible(set_visible);
+    return;
+  }
+
+  if (!animation_.get()) {
+    animation_.reset(new ui::SlideAnimation(this));
+    animation_->SetSlideDuration(GetAnimationDurationMS());
+    animation_->SetTweenType(ui::Tween::LINEAR);
+    animation_->Reset(visible() ? 1.0 : 0.0);
+  }
+
+  if (!set_visible) {
+    animation_->Hide();
+    AnimationProgressed(animation_.get());
+  } else {
+    animation_->Show();
+    AnimationProgressed(animation_.get());
+    views::View::SetVisible(true);
+  }
+}
+
+void TrayItemView::ApplyChange() {
+  // Forcing the widget to the new size is sufficient. The positioning is
+  // taken care of by the layout manager (ShelfLayoutManager).
+  GetWidget()->SetSize(GetWidget()->GetContentsView()->GetPreferredSize());
+}
+
+gfx::Size TrayItemView::DesiredSize() {
+  return views::View::GetPreferredSize();
+}
+
+int TrayItemView::GetAnimationDurationMS() {
+  return kTrayItemAnimationDurationMS;
+}
+
+gfx::Size TrayItemView::GetPreferredSize() {

[Ben Goodger (Google), 2012/04/23 15:33:42]

.cc function order must match .h

[sadrul, 2012/04/23 16:07:58]

Fixed.

+  gfx::Size size = DesiredSize();
+  size.set_height(kTrayIconHeight);
+  if (!animation_.get() || !animation_->is_animating())
+    return size;
+  size.set_width(std::max(1,
+      static_cast<int>(size.width() * animation_->GetCurrentValue())));
+  return size;
+}
+
+void TrayItemView::PreferredSizeChanged() {
+  views::View::PreferredSizeChanged();
+  ApplyChange();
+}
+
+void TrayItemView::AnimationProgressed(const ui::Animation* animation) {
+  ui::Transform transform;
+  transform.SetScale(animation->GetCurrentValue(),
+                     animation->GetCurrentValue());
+  transform.ConcatTranslate(0, animation->CurrentValueBetween(
+      static_cast<double>(height()) / 2, 0.));
+  layer()->SetTransform(transform);
+  ApplyChange();
+}
+
+void TrayItemView::AnimationEnded(const ui::Animation* animation) {
+  if (animation->GetCurrentValue() < 0.1)
+    views::View::SetVisible(false);
+}
+
+void TrayItemView::AnimationCanceled(const ui::Animation* animation) {
+  AnimationEnded(animation);
+}
+
+}  // namespace internal
+}  // namespace ash