title: What Should I Do with the error RecyclerView: No adapter attached; skipping layout
body: <p>I want to fetch images from mysql server into recycler view. When I run my app. I face the following problem:</p>
  
  <blockquote>
    <p>02-25 19:47:47.075 653-12579/? E/WakeLock: GCM_HB_ALARM release
    without a matched acquire! 02-25 19:47:53.241 69-403/? E/FastThread:
    did not receive expected priority boost 02-25 19:47:53.393
    14523-14523/com.example.wiqarali.tourismapp E/RecyclerView: No adapter
    attached; skipping layout 02-25 19:47:53.466
    14523-14523/com.example.wiqarali.tourismapp E/EventBus: Could not
    dispatch event: class
    com.example.wiqarali.tourismapp.serverclasses.GalleryEventBus to
    subscribing class class
    com.example.wiqarali.tourismapp.GalleryActivity
        java.lang.NullPointerException: Attempt to invoke virtual method 'void
    android.support.v7.widget.RecyclerView.setLayoutManager(android.support.v7.widget.RecyclerView$LayoutManager)'
    on a null object reference
            at com.example.wiqarali.tourismapp.GalleryActivity.onMessageEvent(GalleryActivity.java:131)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at org.greenrobot.eventbus.EventBus.invokeSubscriber(EventBus.java:507)
            at org.greenrobot.eventbus.EventBus.postToSubscription(EventBus.java:434)
            at org.greenrobot.eventbus.EventBus.postSingleEventForEventType(EventBus.java:411)
            at org.greenrobot.eventbus.EventBus.postSingleEvent(EventBus.java:384)
            at org.greenrobot.eventbus.EventBus.post(EventBus.java:265)
            at com.example.wiqarali.tourismapp.serverclasses.GetImages$1.onResponse(GetImages.java:59)
            at com.example.wiqarali.tourismapp.serverclasses.GetImages$1.onResponse(GetImages.java:37)
            at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:82)
            at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:29)
            at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:102)
            at android.os.Handler.handleCallback(Handler.java:739)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:135)</p>
  </blockquote>
  
  <p>Here is my event bus code</p>
  
  <pre><code>@Subscribe(threadMode = ThreadMode.MAIN)
  public void onMessageEvent(GalleryEventBus eventBus){
      LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
      recyclerView_gallery.setLayoutManager(linearLayoutManager);
      recyclerView_gallery.setItemAnimator(new DefaultItemAnimator());
      GalleryAdapter adapter = new GalleryAdapter(this, eventBus.galleryList);
      recyclerView_gallery.setAdapter(adapter);
      adapter.notifyDataSetChanged();
  }
  </code></pre>