Improve application Thread safety.

app/src/main/java/com/fox2code/mmm/background/BackgroundBootListener.java

@@ -5,8 +5,6 @@ import android.content.Context;
 import android.content.Intent;
 
 import com.fox2code.mmm.MainApplication;
-import com.fox2code.mmm.installer.InstallerInitializer;
-import com.fox2code.mmm.manager.ModuleManager;
 
 public class BackgroundBootListener extends BroadcastReceiver {
     private static final String BOOT_COMPLETED = "android.intent.action.BOOT_COMPLETED";
@@ -20,17 +18,5 @@ public class BackgroundBootListener extends BroadcastReceiver {
                 BackgroundUpdateChecker.doCheck(context);
             }
         }
-        if (ModuleManager.FORCE_NEED_FALLBACK &&
-                MainApplication.hasGottenRootAccess()) {
-            InstallerInitializer.tryGetMagiskPathAsync(new InstallerInitializer.Callback() {
-                @Override
-                public void onPathReceived(String path) {
-                    ModuleManager.getINSTANCE().scan();
-                }
-
-                @Override
-                public void onFailure(int error) {}
-            });
-        }
     }
 }

app/src/main/java/com/fox2code/mmm/background/BackgroundUpdateChecker.java

@@ -54,8 +54,9 @@ public class BackgroundUpdateChecker extends Worker {
 
     static void doCheck(Context context) {
         Thread.currentThread().setPriority(Thread.MIN_PRIORITY);
+        ModuleManager.getINSTANCE().scanAsync();
         RepoManager.getINSTANCE().update(null);
-        ModuleManager.getINSTANCE().scan();
+        ModuleManager.getINSTANCE().runAfterScan(() -> {
             int moduleUpdateCount = 0;
             HashMap<String, RepoModule> repoModules =
                     RepoManager.getINSTANCE().getModules();
@@ -76,6 +77,7 @@ public class BackgroundUpdateChecker extends Worker {
             if (moduleUpdateCount != 0) {
                 postNotification(context, moduleUpdateCount);
             }
+        });
     }
 
     public static void postNotification(Context context, int updateCount) {

app/src/main/java/com/fox2code/mmm/module/ModuleViewListBuilder.java

@@ -114,6 +114,8 @@ public class ModuleViewListBuilder {
     public void applyTo(final RecyclerView moduleList,final ModuleViewAdapter moduleViewAdapter) {
         if (this.updating) return;
         this.updating = true;
+        ModuleManager.getINSTANCE().afterScan();
+        RepoManager.getINSTANCE().afterUpdate();
         final ArrayList<ModuleHolder> moduleHolders;
         final int newNotificationsLen;
         final boolean first;

app/src/main/java/com/fox2code/mmm/utils/SyncManager.java

@@ -15,6 +15,12 @@ public abstract class SyncManager {
     private boolean syncing;
     private long lastSync;
 
+    public final void scanAsync() {
+        if (!this.syncing) {
+            new Thread(this::scan, "Scan Thread").start();
+        }
+    }
+
     public final void scan() {
         this.update(null);
     }