Only need unlock when process is paused

app/src/main/java/com/hippo/ehviewer/EhApplication.java

@@ -38,6 +38,9 @@ import androidx.appcompat.app.AlertDialog;
 import androidx.appcompat.app.AppCompatDelegate;
 import androidx.collection.LruCache;
 import androidx.core.os.LocaleListCompat;
+import androidx.lifecycle.DefaultLifecycleObserver;
+import androidx.lifecycle.LifecycleOwner;
+import androidx.lifecycle.ProcessLifecycleOwner;
 
 import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 import com.hippo.Native;
@@ -104,6 +107,8 @@ public class EhApplication extends SceneApplication {
     private static final boolean DEBUG_PRINT_IMAGE_COUNT = false;
     private static final long DEBUG_PRINT_INTERVAL = 3000L;
 
+    public static boolean locked = false;
+
     private static EhApplication instance;
 
     private final IntIdGenerator mIdGenerator = new IntIdGenerator();
@@ -297,9 +302,17 @@ public class EhApplication extends SceneApplication {
         return application.mFavouriteStatusRouter;
     }
 
+    static class EhlifecycleObserver implements DefaultLifecycleObserver {
+        @Override
+        public void onPause(@NonNull LifecycleOwner owner) {
+            locked = true;
+        }
+    }
+
     @SuppressLint("StaticFieldLeak")
     @Override
     public void onCreate() {
+        ProcessLifecycleOwner.get().getLifecycle().addObserver(new EhlifecycleObserver());
         instance = this;
 
         Thread.UncaughtExceptionHandler handler = Thread.getDefaultUncaughtExceptionHandler();

app/src/main/java/com/hippo/ehviewer/ui/MainActivity.java

@@ -47,6 +47,7 @@ import com.google.android.material.navigation.NavigationView;
 import com.google.android.material.snackbar.Snackbar;
 import com.hippo.app.EditTextDialogBuilder;
 import com.hippo.ehviewer.AppConfig;
+import com.hippo.ehviewer.EhApplication;
 import com.hippo.ehviewer.R;
 import com.hippo.ehviewer.Settings;
 import com.hippo.ehviewer.client.EhTagDatabase;
@@ -420,7 +421,7 @@ public final class MainActivity extends StageActivity
 
     @Override
     protected void onResume() {
-        if (Settings.getSecurity() && SecurityScene.Companion.isAuthenticationSupported(this)) {
+        if (Settings.getSecurity() && SecurityScene.Companion.isAuthenticationSupported(this) && EhApplication.locked) {
             startScene(new Announcer(SecurityScene.class), true);
         }
         super.onResume();

app/src/main/java/com/hippo/ehviewer/ui/scene/SecurityScene.kt

@@ -27,6 +27,7 @@ import androidx.biometric.auth.AuthPromptCallback
 import androidx.biometric.auth.startClass2BiometricOrCredentialAuthentication
 import androidx.core.content.ContextCompat
 import androidx.fragment.app.FragmentActivity
+import com.hippo.ehviewer.EhApplication
 import com.hippo.ehviewer.R
 
 class SecurityScene : SolidScene() {
@@ -82,6 +83,7 @@ class SecurityScene : SolidScene() {
     }
 
     private fun onSuccess() {
+        EhApplication.locked = false
         if (stackIndex == 0)
             startSceneForCheckStep(CHECK_STEP_SECURITY, arguments)
         finish()