Create a prominent omnibox UI element to add pages to the app launcher.

chrome/browser/ui/views/location_bar/add_to_app_launcher_view.cc

Index: chrome/browser/ui/views/location_bar/add_to_app_launcher_view.cc
diff --git a/chrome/browser/ui/views/location_bar/add_to_app_launcher_view.cc b/chrome/browser/ui/views/location_bar/add_to_app_launcher_view.cc
new file mode 100644
index 0000000000000000000000000000000000000000..a9bc3768a1706ae8a0c99dbe8372193d49d2c209
--- /dev/null
+++ b/chrome/browser/ui/views/location_bar/add_to_app_launcher_view.cc
@@ -0,0 +1,177 @@
+// Copyright 2014 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/location_bar/add_to_app_launcher_view.h"
+
+#include "base/command_line.h"
+#include "base/strings/utf_string_conversions.h"
+#include "chrome/browser/ui/views/location_bar/location_bar_view.h"
+#include "chrome/common/chrome_switches.h"
+#include "content/public/browser/web_contents.h"
+#include "grit/generated_resources.h"
+#include "grit/theme_resources.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/base/resource/resource_bundle.h"
+#include "ui/gfx/color_utils.h"
+#include "ui/views/controls/image_view.h"
+#include "ui/views/controls/label.h"
+#include "url/gurl.h"
+
+namespace {
+
+// TODO(benwells): Refactor common code between this and
+// ContentSettingImageView.
+const int kBackgroundImages[] = IMAGE_GRID(IDR_OMNIBOX_CONTENT_SETTING_BUBBLE);
+const int kStayOpenTimeMS = 3200;  // Time spent with animation fully open.
+
+const int kOpenTimeMS = 150;
+const int kAnimationDurationMS = (kOpenTimeMS * 2) + kStayOpenTimeMS;
+
+// Amount of padding at the edges of the bubble.  If |by_icon| is true, this
+// is the padding next to the icon; otherwise it's the padding next to the
+// label.  (We increase padding next to the label by the amount of padding
+// "built in" to the icon in order to make the bubble appear to have
+// symmetrical padding.)
+int GetBubbleOuterPadding(bool by_icon) {
+  return LocationBarView::kItemPadding - LocationBarView::kBubblePadding +
+      (by_icon ? 0 : LocationBarView::kIconInternalPadding);
+}
+
+int GetTotalSpacingWhileAnimating() {
+  return GetBubbleOuterPadding(true) + LocationBarView::kItemPadding +
+      GetBubbleOuterPadding(false);
+}
+
+}  // namespace
+
+AddToAppLauncherView::AddToAppLauncherView(LocationBarView* parent,
+                                           const gfx::FontList& font_list,
+                                           SkColor text_color,
+                                           SkColor parent_background_color)
+    : parent_(parent),
+      background_painter_(
+          views::Painter::CreateImageGridPainter(kBackgroundImages)),
+      icon_(new views::ImageView),
+      text_label_(new views::Label(base::string16(), font_list)),
+      slide_animator_(this) {
+  icon_->SetHorizontalAlignment(views::ImageView::LEADING);
+  icon_->SetImage(ui::ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
+      IDR_BOOKMARK_BAR_APPS_SHORTCUT));
+  icon_->SetTooltipText(
+      base::UTF8ToUTF16(l10n_util::GetStringUTF8(IDS_ADD_TO_APP_LIST_HINT)));
+  AddChildView(icon_);
+
+  text_label_->SetVisible(false);
+  text_label_->SetEnabledColor(text_color);
+  // Calculate the actual background color for the label.  The background images
+  // are painted atop |parent_background_color|.  We grab the color of the
+  // middle pixel of the middle image of the background, which we treat as the
+  // representative color of the entire background (reasonable, given the
+  // current appearance of these images).  Then we alpha-blend it over the
+  // parent background color to determine the actual color the label text will
+  // sit atop.
+  const SkBitmap& bitmap(
+      ui::ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
+          kBackgroundImages[4])->GetRepresentation(1.0f).sk_bitmap());
+  SkAutoLockPixels pixel_lock(bitmap);
+  SkColor background_image_color =
+      bitmap.getColor(bitmap.width() / 2, bitmap.height() / 2);
+  // Tricky bit: We alpha blend an opaque version of |background_image_color|
+  // against |parent_background_color| using the original image grid color's
+  // alpha. This is because AlphaBlend(a, b, 255) always returns |a| unchanged
+  // even if |a| is a color with non-255 alpha.
+  text_label_->SetBackgroundColor(
+      color_utils::AlphaBlend(SkColorSetA(background_image_color, 255),
+                              parent_background_color,
+                              SkColorGetA(background_image_color)));
+  text_label_->SetHorizontalAlignment(gfx::ALIGN_LEFT);
+  text_label_->SetElideBehavior(gfx::TRUNCATE);
+  text_label_->SetText(base::UTF8ToUTF16(
+      l10n_util::GetStringUTF8(IDS_ADD_TO_APP_LIST_NOTIFICATION_TEXT)));
+  AddChildView(text_label_);
+
+  slide_animator_.SetSlideDuration(kAnimationDurationMS);
+  slide_animator_.SetTweenType(gfx::Tween::LINEAR);
+}
+
+AddToAppLauncherView::~AddToAppLauncherView() {
+}
+
+void AddToAppLauncherView::Update(content::WebContents* web_contents) {
+  SetVisible(false);

[Peter Kasting, 2014/06/12 17:26:08]

Nit: No need to go fix this now, but when you touch this file again, I suggest
moving this into the conditional below, since SetVisible() could cause things
like repaints or whatever, so minimizing the number of times it is called is
probably good.

+
+  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+  if (!command_line->HasSwitch(switches::kEnableProminentURLAppFlow) ||
+      !command_line->HasSwitch(switches::kEnableStreamlinedHostedApps) ||
+      !web_contents || web_contents->IsLoading() ||
+      !web_contents->GetLastCommittedURL().SchemeIsHTTPOrHTTPS()) {
+    slide_animator_.Reset();
+    return;
+  }
+
+  SetVisible(true);
+
+  if (!slide_animator_.is_animating()) {
+    text_label_->SetVisible(true);
+    slide_animator_.Show();
+  }
+}
+
+void AddToAppLauncherView::AnimationEnded(const gfx::Animation* animation) {
+  slide_animator_.Reset();
+  text_label_->SetVisible(false);
+  AnimationProgressed(animation);
+}
+
+void AddToAppLauncherView::AnimationProgressed(
+    const gfx::Animation* animation) {
+  parent_->Layout();
+  parent_->SchedulePaint();
+}
+
+void AddToAppLauncherView::AnimationCanceled(const gfx::Animation* animation) {
+  AnimationEnded(animation);
+}
+
+gfx::Size AddToAppLauncherView::GetPreferredSize() const {
+  // Height will be ignored by the LocationBarView.
+  gfx::Size size(icon_->GetPreferredSize());
+  if (slide_animator_.is_animating()) {
+    double state = slide_animator_.GetCurrentValue();
+    // The fraction of the animation we'll spend animating the string into view,
+    // which is also the fraction we'll spend animating it closed; total
+    // animation (slide out, show, then slide in) is 1.0.
+    const double kOpenFraction =
+        static_cast<double>(kOpenTimeMS) / kAnimationDurationMS;
+    double size_fraction = 1.0;
+    if (state < kOpenFraction)
+      size_fraction = state / kOpenFraction;
+    if (state > (1.0 - kOpenFraction))
+      size_fraction = (1.0 - state) / kOpenFraction;
+    size.Enlarge(
+        size_fraction * (text_label_->GetPreferredSize().width() +
+            GetTotalSpacingWhileAnimating()), 0);
+    size.SetToMax(background_painter_->GetMinimumSize());
+  }
+  return size;
+}
+
+void AddToAppLauncherView::Layout() {
+  const int icon_width = icon_->GetPreferredSize().width();
+  icon_->SetBounds(
+      std::min((width() - icon_width) / 2, GetBubbleOuterPadding(true)),
+      0,
+      icon_width,
+      height());
+  text_label_->SetBounds(
+      icon_->bounds().right() + LocationBarView::kItemPadding,
+      0,
+      std::max(width() - GetTotalSpacingWhileAnimating() - icon_width, 0),
+      height());
+}
+
+void AddToAppLauncherView::OnPaintBackground(gfx::Canvas* canvas) {
+  if (slide_animator_.is_animating())
+    background_painter_->Paint(canvas, size());
+}