Add "Devices available" sublabel to quick settings Cast feature tile

With QsRevamp the quick settings Cast feature tile has a "devices
available" sub-label when:
* Cast devices are available on the network ("sinks")
* Access code casting is available

Bug: b:252872586
Test: added to ash_unittests
Change-Id: I29e6965976d525bdb444a03a5ede757196eb4b54
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4103203
Reviewed-by: Jiaming Cheng <jiamingc@chromium.org>
Commit-Queue: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1083165}

ash/ash_strings.grd

@@ -480,6 +480,9 @@ Style notes:
       <message name="IDS_ASH_STATUS_TRAY_CAST_SHORT" desc="The label used for Cast button in system tray bubble. [CHAR_LIMIT=14]">
         Cast
       </message>
+      <message name="IDS_ASH_STATUS_TRAY_CAST_DEVICES_AVAILABLE" desc="Subtitle under the Cast button in the system tray bubble when Chromecast devices are available for casting">
+        Devices available
+      </message>
       <message name="IDS_ASH_STATUS_TRAY_CAST_TOOLTIP" desc="The tooltip text used for Cast button in system tray bubble.">
         Show cast devices
       </message>

ash/ash_strings_grd/IDS_ASH_STATUS_TRAY_CAST_DEVICES_AVAILABLE.png.sha1

@@ -0,0 +1 @@
+c35a1d6ab1a9cee8df1789a5720288b62ac31c8a

ash/system/cast/cast_feature_pod_controller.cc

@@ -30,7 +30,7 @@ CastFeaturePodController::CastFeaturePodController(
     : tray_controller_(tray_controller) {}
 
 CastFeaturePodController::~CastFeaturePodController() {
-  if (CastConfigController::Get() && button_)
+  if (CastConfigController::Get() && (button_ || tile_))
     CastConfigController::Get()->RemoveObserver(this);
 }
 
@@ -60,10 +60,11 @@ std::unique_ptr<FeatureTile> CastFeaturePodController::CreateTile() {
   DCHECK(features::IsQsRevampEnabled());
   auto tile = std::make_unique<FeatureTile>(base::BindRepeating(
       &CastFeaturePodController::OnIconPressed, weak_factory_.GetWeakPtr()));
+  tile_ = tile.get();
   tile->SetVectorIcon(kUnifiedMenuCastIcon);
   tile->SetLabel(l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_CAST));
-  // TODO(b/252872586): Show sublabel with cast device availability.
-  tile->SetSubLabelVisibility(false);
+  tile->SetSubLabel(
+      l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_CAST_DEVICES_AVAILABLE));
   const std::u16string tooltip =
       l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_CAST_TOOLTIP);
   tile->SetTooltipText(tooltip);
@@ -82,6 +83,12 @@ std::unique_ptr<FeatureTile> CastFeaturePodController::CreateTile() {
     TrackVisibilityUMA();
   tile->SetVisible(visible);
 
+  // Refresh cast devices to update the "Devices available" sublabel visibility.
+  if (cast_config) {
+    cast_config->AddObserver(this);
+    cast_config->RequestDeviceRefresh();
+  }
+  UpdateSublabelVisibility();
   return tile;
 }
 
@@ -116,8 +123,10 @@ void CastFeaturePodController::OnLabelPressed() {
 
 void CastFeaturePodController::OnDevicesUpdated(
     const std::vector<SinkAndRoute>& devices) {
-  DCHECK(!features::IsQsRevampEnabled());
-  Update();
+  if (features::IsQsRevampEnabled())
+    UpdateSublabelVisibility();
+  else
+    Update();
 }
 
 void CastFeaturePodController::Update() {
@@ -132,4 +141,14 @@ void CastFeaturePodController::Update() {
   button_->SetVisible(visible);
 }
 
+void CastFeaturePodController::UpdateSublabelVisibility() {
+  DCHECK(features::IsQsRevampEnabled());
+  DCHECK(tile_);
+  auto* cast_config = CastConfigController::Get();
+  bool devices_available =
+      cast_config && (cast_config->HasSinksAndRoutes() ||
+                      cast_config->AccessCodeCastingEnabled());
+  tile_->SetSubLabelVisibility(devices_available);
+}
+
 }  // namespace ash

ash/system/cast/cast_feature_pod_controller.h

@@ -39,11 +39,17 @@ class ASH_EXPORT CastFeaturePodController
   void OnDevicesUpdated(const std::vector<SinkAndRoute>& devices) override;
 
  private:
+  // Updates feature pod button visibility. Used pre-QsRevamp.
   void Update();
 
-  // Unowned.
+  // Updates tile sublabel visibility. Used post-QsRevamp.
+  void UpdateSublabelVisibility();
+
   UnifiedSystemTrayController* const tray_controller_;
+
+  // Owned by views hierarchy.
   FeaturePodButton* button_ = nullptr;
+  FeatureTile* tile_ = nullptr;
 
   base::WeakPtrFactory<CastFeaturePodController> weak_factory_{this};
 };

ash/system/cast/cast_feature_pod_controller_unittest.cc

@@ -28,9 +28,11 @@ class TestCastConfigController : public CastConfigController {
   bool HasMediaRouterForPrimaryProfile() const override {
     return has_media_router_;
   }
-  bool HasSinksAndRoutes() const override { return false; }
+  bool HasSinksAndRoutes() const override { return has_sinks_and_routes_; }
   bool HasActiveRoute() const override { return false; }
-  bool AccessCodeCastingEnabled() const override { return false; }
+  bool AccessCodeCastingEnabled() const override {
+    return access_code_casting_enabled_;
+  }
   void RequestDeviceRefresh() override {}
   const std::vector<SinkAndRoute>& GetSinksAndRoutes() override {
     return sinks_and_routes_;
@@ -39,6 +41,8 @@ class TestCastConfigController : public CastConfigController {
   void StopCasting(const std::string& route_id) override {}
 
   bool has_media_router_ = true;
+  bool has_sinks_and_routes_ = false;
+  bool access_code_casting_enabled_ = false;
   std::vector<SinkAndRoute> sinks_and_routes_;
 };
 
@@ -79,5 +83,34 @@ TEST_F(CastFeaturePodControllerTest, TileNotVisibleWhenNoMediaRouter) {
   EXPECT_FALSE(tile->GetVisible());
 }
 
+TEST_F(CastFeaturePodControllerTest, SubLabelVisibleWhenSinksAvailable) {
+  // When cast devices are available, the sub-label is visible.
+  cast_config_.has_sinks_and_routes_ = true;
+  std::unique_ptr<FeatureTile> tile = controller_->CreateTile();
+  EXPECT_TRUE(tile->sub_label()->GetVisible());
+  EXPECT_EQ(tile->sub_label()->GetText(), u"Devices available");
+}
+
+TEST_F(CastFeaturePodControllerTest,
+       SubLabelVisibleWhenAccessCodeCastingEnabled) {
+  // When access code casting is available, the sub-label is visible.
+  cast_config_.access_code_casting_enabled_ = true;
+  std::unique_ptr<FeatureTile> tile = controller_->CreateTile();
+  EXPECT_TRUE(tile->sub_label()->GetVisible());
+  EXPECT_EQ(tile->sub_label()->GetText(), u"Devices available");
+}
+
+TEST_F(CastFeaturePodControllerTest, SubLabelVisibleOnDevicesUpdated) {
+  // By default the sub-label is hidden.
+  std::unique_ptr<FeatureTile> tile = controller_->CreateTile();
+  EXPECT_FALSE(tile->sub_label()->GetVisible());
+
+  // If cast devices become available while the tray is open, the sub-label
+  // becomes visible.
+  cast_config_.has_sinks_and_routes_ = true;
+  controller_->OnDevicesUpdated({});
+  EXPECT_TRUE(tile->sub_label()->GetVisible());
+}
+
 }  // namespace
 }  // namespace ash

ash/system/unified/feature_tile.h

@@ -94,6 +94,7 @@ class ASH_EXPORT FeatureTile : public views::Button {
   // Sets the tooltip text of `drill_container_` and `drill_in_button_`.
   void SetDrillInButtonTooltipText(const std::u16string& text);
 
+  views::Label* sub_label() { return sub_label_; }
   views::LabelButton* drill_in_button() { return drill_in_button_; }
 
  private: