[LeBroadcast] Fix the NullPointerException for launching dialog

Since the BluetoothLeBroadcastMetadata is null, and it causes the
NullPointerException.
After the system starts broadcast, the framework sends two
callbacks, first is onBroadcastStarted, and second one is
onBroadcastMetadataChanged. The BluetoothLeBroadcastMetadata object
is created before onBroadcastMetadataChanged. Therefore,the app
needs to wait the onBroadcastMetadataChanged, and then launchs the
broadcast dialog. If the app launchs after the onBroadcastStarted,
then the broadcast dialog can't get the null
BluetoothLeBroadcastMetadata and it causes UI show the wrong QR code.

Bug: 237976782
Test: build pass and manually test

Change-Id: I91a28079ae01bbc5cc4c3ce9331741f0b4ee81c0

packages/SettingsLib/src/com/android/settingslib/bluetooth/LocalBluetoothLeBroadcast.java

@@ -299,6 +299,18 @@ public class LocalBluetoothLeBroadcast implements LocalBluetoothProfile {
     }
 
     public BluetoothLeBroadcastMetadata getLatestBluetoothLeBroadcastMetadata() {
+        if (mService == null) {
+            Log.d(TAG, "The BluetoothLeBroadcast is null");
+            return null;
+        }
+        if (mBluetoothLeBroadcastMetadata == null) {
+            final List<BluetoothLeBroadcastMetadata> metadataList =
+                    mService.getAllBroadcastMetadata();
+            mBluetoothLeBroadcastMetadata = metadataList.stream()
+                    .filter(i -> i.getBroadcastId() == mBroadcastId)
+                    .findFirst()
+                    .orElse(null);
+        }
         return mBluetoothLeBroadcastMetadata;
     }
 
@@ -368,7 +380,12 @@ public class LocalBluetoothLeBroadcast implements LocalBluetoothProfile {
     }
 
     public LocalBluetoothLeBroadcastMetadata getLocalBluetoothLeBroadcastMetaData() {
-        return new LocalBluetoothLeBroadcastMetadata(mBluetoothLeBroadcastMetadata);
+        final BluetoothLeBroadcastMetadata metadata = getLatestBluetoothLeBroadcastMetadata();
+        if (metadata == null) {
+            Log.d(TAG, "The BluetoothLeBroadcastMetadata is null.");
+            return null;
+        }
+        return new LocalBluetoothLeBroadcastMetadata(metadata);
     }
 
     public boolean isProfileReady() {

packages/SystemUI/src/com/android/systemui/media/dialog/MediaOutputBaseDialog.java

@@ -100,6 +100,7 @@ public abstract class MediaOutputBaseDialog extends SystemUIDialog implements
     private int mListMaxHeight;
     private WallpaperColors mWallpaperColors;
     private Executor mExecutor;
+    private boolean mShouldLaunchLeBroadcastDialog;
 
     MediaOutputBaseAdapter mAdapter;
 
@@ -394,7 +395,9 @@ public abstract class MediaOutputBaseDialog extends SystemUIDialog implements
     }
 
     public void handleLeBroadcastStarted() {
-        startLeBroadcastDialog();
+        // Waiting for the onBroadcastMetadataChanged. The UI launchs the broadcast dialog when
+        // the metadata is ready.
+        mShouldLaunchLeBroadcastDialog = true;
     }
 
     public void handleLeBroadcastStartFailed() {
@@ -404,10 +407,15 @@ public abstract class MediaOutputBaseDialog extends SystemUIDialog implements
     }
 
     public void handleLeBroadcastMetadataChanged() {
+        if (mShouldLaunchLeBroadcastDialog) {
+            startLeBroadcastDialog();
+            mShouldLaunchLeBroadcastDialog = false;
+        }
         refresh();
     }
 
     public void handleLeBroadcastStopped() {
+        mShouldLaunchLeBroadcastDialog = false;
         refresh();
     }
 

packages/SystemUI/src/com/android/systemui/media/dialog/MediaOutputController.java

@@ -62,6 +62,7 @@ import com.android.settingslib.RestrictedLockUtilsInternal;
 import com.android.settingslib.Utils;
 import com.android.settingslib.bluetooth.BluetoothUtils;
 import com.android.settingslib.bluetooth.LocalBluetoothLeBroadcast;
+import com.android.settingslib.bluetooth.LocalBluetoothLeBroadcastMetadata;
 import com.android.settingslib.bluetooth.LocalBluetoothManager;
 import com.android.settingslib.media.InfoMediaManager;
 import com.android.settingslib.media.LocalMediaManager;
@@ -847,7 +848,9 @@ public class MediaOutputController implements LocalMediaManager.DeviceCallback,
             Log.d(TAG, "getBroadcastMetadata: LE Audio Broadcast is null");
             return "";
         }
-        return broadcast.getLocalBluetoothLeBroadcastMetaData().convertToQrCodeString();
+        final LocalBluetoothLeBroadcastMetadata metadata =
+                broadcast.getLocalBluetoothLeBroadcastMetaData();
+        return metadata != null ? metadata.convertToQrCodeString() : "";
     }
 
     boolean isActiveRemoteDevice(@NonNull MediaDevice device) {