CrOS GMC: Add empty state to gmc dialog.

This CL modifies media tray bubble behavior such that when the dialog
is opened and all media stops playing, we will show an empty state
indicating there's no media playing instead of close the dialog
immediately.

Bug: 1134414
Change-Id: I3f0f2489da2189e6a71f74f6a00855d8b4a535f1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2444529Reviewed-by: Tetsui Ohkubo <tetsui@chromium.org>
Reviewed-by: Tommy Steimel <steimel@chromium.org>
Commit-Queue: Jazz Xu <jazzhsu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#813279}

ash/system/media/media_tray.cc

@@ -31,11 +31,13 @@
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/layout/box_layout.h"
+#include "ui/views/layout/fill_layout.h"
 
 namespace ash {
 
 namespace {
 
+constexpr int kNoMediaTextFontSizeIncrease = 2;
 constexpr int kTitleFontSizeIncrease = 4;
 constexpr int kTitleViewHeight = 56;
 
@@ -257,7 +259,7 @@ void MediaTray::ShowBubble(bool show_by_click) {
   title_view->layer()->SetFillsBoundsOpaquely(false);
   pin_button_ = title_view->pin_button();
 
-  bubble_view->AddChildView(
+  content_view_ = bubble_view->AddChildView(
       MediaNotificationProvider::Get()->GetMediaNotificationListView(
           AshColorProvider::Get()->GetContentLayerColor(
               AshColorProvider::ContentLayerType::kSeparatorColor),
@@ -272,6 +274,7 @@ void MediaTray::CloseBubble() {
   if (MediaNotificationProvider::Get())
     MediaNotificationProvider::Get()->OnBubbleClosing();
   SetIsActive(false);
+  empty_state_view_ = nullptr;
   bubble_.reset();
   shelf()->UpdateAutoHideState();
 }
@@ -303,19 +306,57 @@ void MediaTray::UpdateDisplayState() {
   if (!MediaNotificationProvider::Get())
     return;
 
-  bool should_show =
-      (MediaNotificationProvider::Get()->HasActiveNotifications() ||
-       MediaNotificationProvider::Get()->HasFrozenNotifications()) &&
-      !Shell::Get()->session_controller()->IsScreenLocked();
-
-  if (!should_show && bubble_)
+  if (bubble_ && Shell::Get()->session_controller()->IsScreenLocked())
     CloseBubble();
 
-  SetVisiblePreferred(should_show && IsPinnedToShelf());
+  bool has_session =
+      MediaNotificationProvider::Get()->HasActiveNotifications() ||
+      MediaNotificationProvider::Get()->HasFrozenNotifications();
+
+  if (bubble_ && !has_session)
+    ShowEmptyState();
+
+  bool should_show = has_session &&
+                     !Shell::Get()->session_controller()->IsScreenLocked() &&
+                     IsPinnedToShelf();
+
+  SetVisiblePreferred(should_show);
 }
 
 void MediaTray::OnGlobalMediaControlsPinPrefChanged() {
   UpdateDisplayState();
 }
 
+void MediaTray::ShowEmptyState() {
+  DCHECK(content_view_);
+  if (empty_state_view_)
+    return;
+
+  // Create and add empty state view containing a label indicating there's no
+  // active session
+  auto empty_state_view = std::make_unique<views::View>();
+  auto* layout =
+      empty_state_view->SetLayoutManager(std::make_unique<views::BoxLayout>(
+          views::BoxLayout::Orientation::kHorizontal));
+  layout->set_minimum_cross_axis_size(content_view_->bounds().height());
+  layout->set_main_axis_alignment(views::BoxLayout::MainAxisAlignment::kCenter);
+
+  auto no_media_label = std::make_unique<views::Label>();
+  no_media_label->SetAutoColorReadabilityEnabled(false);
+  no_media_label->SetSubpixelRenderingEnabled(false);
+  no_media_label->SetEnabledColor(AshColorProvider::Get()->GetContentLayerColor(
+      AshColorProvider::ContentLayerType::kTextColorSecondary));
+  no_media_label->SetText(
+      l10n_util::GetStringUTF16(IDS_ASH_GLOBAL_MEDIA_CONTROLS_NO_MEDIA_TEXT));
+  no_media_label->SetFontList(
+      views::Label::GetDefaultFontList().DeriveWithSizeDelta(
+          kNoMediaTextFontSizeIncrease));
+  empty_state_view->AddChildView(std::move(no_media_label));
+
+  empty_state_view->SetPaintToLayer();
+  empty_state_view->layer()->SetFillsBoundsOpaquely(false);
+  empty_state_view_ =
+      bubble_->GetBubbleView()->AddChildView(std::move(empty_state_view));
+}
+
 }  // namespace ash

ash/system/media/media_tray.h

@@ -82,6 +82,8 @@ class ASH_EXPORT MediaTray : public MediaNotificationProviderObserver,
   // Called when global media controls pin pref is changed.
   void OnGlobalMediaControlsPinPrefChanged();
 
+  void ShowEmptyState();
+
   // Ptr to pin button in the dialog, owned by the view hierarchy.
   views::Button* pin_button_ = nullptr;
 
@@ -90,6 +92,9 @@ class ASH_EXPORT MediaTray : public MediaNotificationProviderObserver,
 
   // Weak pointer, will be parented by TrayContainer for its lifetime.
   views::ImageView* icon_;
+
+  views::View* content_view_ = nullptr;
+  views::View* empty_state_view_ = nullptr;
 };
 
 }  // namespace ash

ash/system/media/media_tray_unittest.cc

@@ -99,6 +99,8 @@ class MediaTrayTest : public AshTestBase {
 
   MediaTray* media_tray() { return media_tray_; }
 
+  views::View* empty_state_view() { return media_tray_->empty_state_view_; }
+
  private:
   std::unique_ptr<MockMediaNotificationProvider> provider_;
   MediaTray* media_tray_;
@@ -168,7 +170,7 @@ TEST_F(MediaTrayTest, ShowAndHideBubbleTest) {
   EXPECT_FALSE(media_tray()->is_active());
 }
 
-TEST_F(MediaTrayTest, DialogCloseWhenNoActiveNotificationTest) {
+TEST_F(MediaTrayTest, ShowEmptyStateWhenNoActiveNotification) {
   // Media tray should be visible when there is active notification.
   provider()->SetHasActiveNotifications(true);
   SimulateNotificationListChanged();
@@ -185,11 +187,11 @@ TEST_F(MediaTrayTest, DialogCloseWhenNoActiveNotificationTest) {
   EXPECT_TRUE(media_tray()->is_active());
 
   // Bubble should close if there's no active sessions.
-  EXPECT_CALL(*provider(), OnBubbleClosing());
   provider()->SetHasActiveNotifications(false);
   SimulateNotificationListChanged();
-  EXPECT_EQ(GetBubbleWrapper(), nullptr);
+  EXPECT_NE(GetBubbleWrapper(), nullptr);
   EXPECT_FALSE(media_tray()->GetVisible());
+  EXPECT_NE(empty_state_view(), nullptr);
 }
 
 TEST_F(MediaTrayTest, PinButtonTest) {