Attepted fix of NPE in #1783

Author: noah-livio

android/sdl_android/src/main/java/com/smartdevicelink/managers/SdlManager.java

@@ -91,6 +91,16 @@ public class SdlManager extends BaseSdlManager {
     private VideoStreamManager videoStreamManager;
     private AudioStreamManager audioStreamManager;
 
+    private Handler handler = new Handler(Looper.getMainLooper());
+    private Runnable changeRegistrationRunnable = new Runnable() {
+        @Override
+        public void run() {
+            checkLifecycleConfiguration();
+            DebugTool.logInfo(TAG, "Retry Change Registration Count: " + changeRegistrationRetry);
+        }
+    };
+
+
     /**
      * Starts up a SdlManager, and calls provided callback called once all BaseSubManagers are done setting up
      */
@@ -211,14 +221,9 @@ private void notifyDevListener(String info) {
     void retryChangeRegistration() {
         changeRegistrationRetry++;
         if (changeRegistrationRetry < MAX_RETRY) {
-            final Handler handler = new Handler(Looper.getMainLooper());
-            handler.postDelayed(new Runnable() {
-                @Override
-                public void run() {
-                    checkLifecycleConfiguration();
-                    DebugTool.logInfo(TAG, "Retry Change Registration Count: " + changeRegistrationRetry);
-                }
-            }, 3000);
+            if (handler != null && changeRegistrationRunnable != null) {
+                handler.postDelayed(changeRegistrationRunnable, 3000);
+            }
         }
     }
 
@@ -258,6 +263,15 @@ public synchronized void dispose() {
             this.lifecycleManager.stop();
         }
 
+        if (handler != null) {
+            if (changeRegistrationRunnable != null) {
+                handler.removeCallbacks(changeRegistrationRunnable);
+                changeRegistrationRunnable = null;
+            }
+
+            handler = null;
+        }
+
         if (managerListener != null) {
             managerListener.onDestroy();
             managerListener = null;