Support disable extend Fingerprint Settings

1. Disable extend fingerprint settings when all fingerprints removed
2. Refine FingerprintUnlockCategoryController logic to better determine
   available status

Bug: 394550555
Flag: EXEMPT support interface, flag only used in impl part
Test: atest FingerprintSettingsFragmentTest
Change-Id: I8904e5f6d8f475ad63540eaef913407d7c0cf4ad

src/com/android/settings/biometrics/fingerprint/FingerprintSettings.java

@@ -332,6 +332,8 @@ public class FingerprintSettings extends SubSettings {
         private boolean mIsEnrolling;
         /** SaveInstance key if we are waiting activity result from a extension preference */
         @NonNull private String mLaunchedExtPrefKey = "";
+        /** key list for changing visibility */
+        @NonNull private final ArrayList<String> mExtPrefKeys = new ArrayList<>();
 
         private long mChallenge;
 
@@ -474,6 +476,7 @@ public class FingerprintSettings extends SubSettings {
                 if (preference instanceof PrimarySwitchIntentPreference) {
                     preference.setOnPreferenceClickListener(this::onExtIntentPreferenceClick);
                 }
+                mExtPrefKeys.add(preference.getKey());
                 mFingerprintUnlockCategory.addPreference(preference);
             }
         }
@@ -826,8 +829,17 @@ public class FingerprintSettings extends SubSettings {
             updateAddPreference();
         }
 
+        /**
+         * Lambda function for setCategoryHasChildrenSupplier
+         */
+        private boolean fingerprintUnlockCategoryHasChild() {
+            return mFingerprintUnlockCategory.getPreferenceCount() > 0;
+        }
+
         private void addFingerprintUnlockCategory() {
             mFingerprintUnlockCategory = findPreference(KEY_FINGERPRINT_UNLOCK_CATEGORY);
+            mFingerprintUnlockCategoryPreferenceController.setCategoryHasChildrenSupplier(
+                    this::fingerprintUnlockCategoryHasChild);
             if (isSfps()) {
                 // For both SFPS "screen on to auth" and "rest to unlock"
                 final Preference restToUnlockPreference = FeatureFactory.getFeatureFactory()
@@ -867,6 +879,14 @@ public class FingerprintSettings extends SubSettings {
                         mScreenOffUnlockUdfpsPreferenceController.getAvailabilityStatus();
                 updatePreferenceVisibility(status, mScreenOffUnlockUdfpsPreference);
             }
+            if (!mExtPrefKeys.isEmpty()) {
+                for (String key: mExtPrefKeys) {
+                    Preference preference = mFingerprintUnlockCategory.findPreference(key);
+                    if (preference != null) {
+                        updatePreferenceVisibility(categoryStatus, preference);
+                    }
+                }
+            }
         }
 
         private void updatePreferenceVisibility(int availabilityStatus, Preference preference) {

src/com/android/settings/biometrics/fingerprint/FingerprintUnlockCategoryController.java

@@ -16,8 +16,7 @@
 
 package com.android.settings.biometrics.fingerprint;
 
-import static android.hardware.biometrics.Flags.screenOffUnlockUdfps;
-
+import android.annotation.Nullable;
 import android.content.Context;
 import android.hardware.fingerprint.FingerprintManager;
 
@@ -25,6 +24,8 @@ import com.android.internal.annotations.VisibleForTesting;
 import com.android.settings.Utils;
 import com.android.settings.core.BasePreferenceController;
 
+import java.util.function.Supplier;
+
 /**
  * Preference controller that controls the fingerprint unlock features to be shown / be hidden.
  */
@@ -34,17 +35,31 @@ public class FingerprintUnlockCategoryController extends BasePreferenceControlle
     private int mUserId;
     @VisibleForTesting
     protected FingerprintManager mFingerprintManager;
+    @Nullable
+    private Supplier<Boolean> mCategoryHasChildSupplier = null;
 
     public FingerprintUnlockCategoryController(Context context, String key) {
         super(context, key);
         mFingerprintManager = Utils.getFingerprintManagerOrNull(context);
     }
 
+    public void setCategoryHasChildrenSupplier(
+            @Nullable Supplier<Boolean> categoryHasChildSupplier
+    ) {
+        mCategoryHasChildSupplier = categoryHasChildSupplier;
+    }
+
     @Override
     public int getAvailabilityStatus() {
+        Supplier<Boolean> categoryHasChildSupplier = mCategoryHasChildSupplier;
+        boolean hasChild = false;
+        if (categoryHasChildSupplier != null) {
+            hasChild = categoryHasChildSupplier.get();
+        }
+
         if (mFingerprintManager != null
                 && mFingerprintManager.isHardwareDetected()
-                && (mFingerprintManager.isPowerbuttonFps() || screenOffUnlockUdfps())) {
+                && hasChild) {
             return mFingerprintManager.hasEnrolledTemplates(getUserId())
                     ? AVAILABLE : CONDITIONALLY_UNAVAILABLE;
         } else {