diff --git a/ProtoLibraries.bp b/ProtoLibraries.bp
index c12f5b4..a0944d4 100644
--- a/ProtoLibraries.bp
+++ b/ProtoLibraries.bp
@@ -100,6 +100,8 @@
         ],
         type: "full",
     },
+    // b/267831518: Pin tradefed and dependencies to Java 11.
+    java_version: "11",
     // Protos have lots of MissingOverride and similar.
     errorprone: {
         enabled: false,
diff --git a/packages/SystemUI/res/values/strings.xml b/packages/SystemUI/res/values/strings.xml
index 53f1227..422b049 100644
--- a/packages/SystemUI/res/values/strings.xml
+++ b/packages/SystemUI/res/values/strings.xml
@@ -2348,7 +2348,10 @@
     <string name="media_output_broadcast_update_error">Can\u2019t save. Try again.</string>
     <!-- The error message when Broadcast name/code update failed and can't change again[CHAR LIMIT=60] -->
     <string name="media_output_broadcast_last_update_error">Can\u2019t save.</string>
-
+    <!-- The hint message when Broadcast code is less than 4 characters [CHAR LIMIT=60] -->
+    <string name="media_output_broadcast_code_hint_no_less_than_min">Use at least 4 characters</string>
+    <!-- The hint message when Broadcast code is more than 16 characters [CHAR LIMIT=60] -->
+    <string name="media_output_broadcast_code_hint_no_more_than_max">Use fewer than 16 characters</string>
 
     <!-- Label for clip data when copying the build number off QS [CHAR LIMIT=NONE]-->
     <string name="build_number_clip_data_label">Build number</string>
diff --git a/packages/SystemUI/src/com/android/systemui/media/dialog/MediaOutputBroadcastDialog.java b/packages/SystemUI/src/com/android/systemui/media/dialog/MediaOutputBroadcastDialog.java
index 35baf013..12d6b7c 100644
--- a/packages/SystemUI/src/com/android/systemui/media/dialog/MediaOutputBroadcastDialog.java
+++ b/packages/SystemUI/src/com/android/systemui/media/dialog/MediaOutputBroadcastDialog.java
@@ -20,6 +20,8 @@
 import android.content.Context;
 import android.graphics.Bitmap;
 import android.os.Bundle;
+import android.text.Editable;
+import android.text.TextWatcher;
 import android.text.method.HideReturnsTransformationMethod;
 import android.text.method.PasswordTransformationMethod;
 import android.util.Log;
@@ -64,11 +66,51 @@
     private String mCurrentBroadcastName;
     private String mCurrentBroadcastCode;
     private boolean mIsStopbyUpdateBroadcastCode = false;
+    private TextWatcher mTextWatcher = new TextWatcher() {
+        @Override
+        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
+            // Do nothing
+        }
+
+        @Override
+        public void onTextChanged(CharSequence s, int start, int before, int count) {
+            // Do nothing
+        }
+
+        @Override
+        public void afterTextChanged(Editable s) {
+            if (mAlertDialog == null || mBroadcastErrorMessage == null) {
+                return;
+            }
+            boolean breakBroadcastCodeRuleTextLengthLessThanMin =
+                    s.length() > 0 && s.length() < BROADCAST_CODE_MIN_LENGTH;
+            boolean breakBroadcastCodeRuleTextLengthMoreThanMax =
+                    s.length() > BROADCAST_CODE_MAX_LENGTH;
+            boolean breakRule = breakBroadcastCodeRuleTextLengthLessThanMin
+                    || breakBroadcastCodeRuleTextLengthMoreThanMax;
+
+            if (breakBroadcastCodeRuleTextLengthLessThanMin) {
+                mBroadcastErrorMessage.setText(
+                        R.string.media_output_broadcast_code_hint_no_less_than_min);
+            } else if (breakBroadcastCodeRuleTextLengthMoreThanMax) {
+                mBroadcastErrorMessage.setText(
+                        R.string.media_output_broadcast_code_hint_no_more_than_max);
+            }
+
+            mBroadcastErrorMessage.setVisibility(breakRule ? View.VISIBLE : View.INVISIBLE);
+            Button positiveBtn = mAlertDialog.getButton(AlertDialog.BUTTON_POSITIVE);
+            if (positiveBtn != null) {
+                positiveBtn.setEnabled(breakRule ? false : true);
+            }
+        }
+    };
 
     static final int METADATA_BROADCAST_NAME = 0;
     static final int METADATA_BROADCAST_CODE = 1;
 
     private static final int MAX_BROADCAST_INFO_UPDATE = 3;
+    private static final int BROADCAST_CODE_MAX_LENGTH = 16;
+    private static final int BROADCAST_CODE_MIN_LENGTH = 4;
 
     MediaOutputBroadcastDialog(Context context, boolean aboveStatusbar,
             BroadcastSender broadcastSender, MediaOutputController mediaOutputController) {
@@ -219,6 +261,9 @@
                 R.layout.media_output_broadcast_update_dialog, null);
         final EditText editText = layout.requireViewById(R.id.broadcast_edit_text);
         editText.setText(editString);
+        if (isBroadcastCode) {
+            editText.addTextChangedListener(mTextWatcher);
+        }
         mBroadcastErrorMessage = layout.requireViewById(R.id.broadcast_error_message);
         mAlertDialog = new Builder(mContext)
                 .setTitle(isBroadcastCode ? R.string.media_output_broadcast_code