Crash when clicking Fingerprint Settings 'Learn more' link

NPE when clicking the 'Learn more' link if no helpIntent has
been provided.
Also hide the link icon on the Fingerprint Enroll Introduction
screen if no link/text has been provided.

Bug: 266530752
Test: Manual
Change-Id: I7f16abe5b171a759603329400f840449ea527456

3 files changed, 14 insertions, 6 deletions

diff --git a/res/layout/fingerprint_enroll_introduction.xml b/res/layout/fingerprint_enroll_introduction.xml
index 0c10e52e71..f3faf874bf 100644
--- a/res/layout/fingerprint_enroll_introduction.xml
+++ b/res/layout/fingerprint_enroll_introduction.xml
@@ -185,6 +185,7 @@
             </LinearLayout>
 
             <LinearLayout
+                android:id="@+id/learn_more"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:orientation="horizontal">
diff --git a/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroduction.java b/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroduction.java
index 08fb5c0c5e..20b204c87d 100644
--- a/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroduction.java
+++ b/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroduction.java
@@ -28,9 +28,11 @@ import android.hardware.fingerprint.FingerprintSensorPropertiesInternal;
 import android.os.Bundle;
 import android.text.Html;
 import android.text.method.LinkMovementMethod;
+import android.text.TextUtils;
 import android.util.Log;
 import android.view.View;
 import android.widget.ImageView;
+import android.widget.LinearLayout;
 import android.widget.ScrollView;
 import android.widget.TextView;
 
@@ -107,10 +109,15 @@ public class FingerprintEnrollIntroduction extends BiometricEnrollIntroduction {
         footerMessage5.setText(getFooterMessage5());
         footerMessage6.setText(getFooterMessage6());
 
-        final TextView footerLink = findViewById(R.id.footer_learn_more);
-        footerLink.setMovementMethod(LinkMovementMethod.getInstance());
-        footerLink.setText(Html.fromHtml(getString(getFooterLearnMore()),
-                Html.FROM_HTML_MODE_LEGACY));
+        if (TextUtils.isEmpty(getString(getFooterLearnMore()))) {
+            final LinearLayout learnMoreFooter = findViewById(R.id.learn_more);
+            learnMoreFooter.setVisibility(View.GONE);
+        } else {
+            final TextView footerLink = findViewById(R.id.footer_learn_more);
+            footerLink.setMovementMethod(LinkMovementMethod.getInstance());
+            footerLink.setText(Html.fromHtml(getString(getFooterLearnMore()),
+                    Html.FROM_HTML_MODE_LEGACY));
+        }
 
         if (mCanAssumeUdfps) {
             footerMessage6.setVisibility(View.VISIBLE);
diff --git a/src/com/android/settings/biometrics/fingerprint/FingerprintSettings.java b/src/com/android/settings/biometrics/fingerprint/FingerprintSettings.java
index bbb4f45b70..3d192111c6 100644
--- a/src/com/android/settings/biometrics/fingerprint/FingerprintSettings.java
+++ b/src/com/android/settings/biometrics/fingerprint/FingerprintSettings.java
@@ -419,8 +419,8 @@ public class FingerprintSettings extends SubSettings {
                     activity, DevicePolicyManager.KEYGUARD_DISABLE_FINGERPRINT, mUserId);
             final Intent helpIntent = HelpUtils.getHelpIntent(
                     activity, getString(getHelpResource()), activity.getClass().getName());
-            final View.OnClickListener learnMoreClickListener = (v) ->
-                    activity.startActivityForResult(helpIntent, 0);
+            final View.OnClickListener learnMoreClickListener = helpIntent != null ? (v) ->
+                    activity.startActivityForResult(helpIntent, 0) : null;
 
             mFooterColumns.clear();
             if (admin != null) {