add biometrics disabled hint

app/src/main/java/sh/sar/basedbank/ui/home/SettingsSecurityFragment.kt

@@ -35,8 +35,6 @@ class SettingsSecurityFragment : Fragment() {
         val canUseBiometrics = BiometricManager.from(requireContext())
             .canAuthenticate(BiometricManager.Authenticators.BIOMETRIC_WEAK) == BiometricManager.BIOMETRIC_SUCCESS
         if (canUseBiometrics) {
-            binding.rowBiometrics.visibility = View.VISIBLE
-
             val unlockEnabled = prefs.getBoolean("biometrics_enabled", false)
             binding.switchBiometrics.isChecked = unlockEnabled
             binding.switchBiometricsTransfer.isChecked = prefs.getBoolean("biometrics_transfer_confirm", false)
@@ -54,6 +52,10 @@ class SettingsSecurityFragment : Fragment() {
             binding.switchBiometricsTransfer.setOnCheckedChangeListener { _, isChecked ->
                 prefs.edit().putBoolean("biometrics_transfer_confirm", isChecked).apply()
             }
+        } else {
+            binding.tvBiometricsHint.visibility = View.VISIBLE
+            binding.switchBiometrics.isEnabled = false
+            binding.switchBiometricsTransfer.isEnabled = false
         }
 
         // Auto-lock

app/src/main/res/layout/fragment_settings_security.xml

@@ -31,8 +31,7 @@
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:orientation="vertical"
-            android:layout_marginTop="16dp"
-            android:visibility="gone">
+            android:layout_marginTop="16dp">
 
             <TextView
                 android:layout_width="wrap_content"
@@ -40,7 +39,17 @@
                 android:text="@string/settings_biometrics"
                 android:textAppearance="?attr/textAppearanceTitleSmall"
                 android:textColor="?attr/colorOnSurfaceVariant"
-                android:layout_marginBottom="8dp" />
+                android:layout_marginBottom="4dp" />
+
+            <TextView
+                android:id="@+id/tvBiometricsHint"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="@string/settings_biometrics_unavailable"
+                android:textAppearance="?attr/textAppearanceBodySmall"
+                android:textColor="?attr/colorOnSurfaceVariant"
+                android:layout_marginBottom="8dp"
+                android:visibility="gone" />
 
             <LinearLayout
                 android:layout_width="match_parent"

app/src/main/res/values/strings.xml

@@ -104,6 +104,7 @@
     <string name="settings_security">Security</string>
     <string name="settings_change_lock">Change PIN / Pattern</string>
     <string name="settings_biometrics">Use biometrics</string>
+    <string name="settings_biometrics_unavailable">No biometrics enrolled on this device</string>
     <string name="settings_biometrics_unlock">To unlock app</string>
     <string name="settings_biometrics_transfer">Confirm transfer</string>
     <string name="biometric_transfer_title">Confirm Transfer</string>