Error: Attempt to invoke virtual method 'boolean com.devspark.appmsg.AppMsg.isShowing()' on a null object reference

Hi, I have created two AppMsg object like below,

public MyActivity extends Activity {
     AppMsg noConnectionMsg, connectedMsg; 

    @Override
    public void onCreate(Bundle bundle) {
      noConnectionMsg = AppMsg.makeText(this,
                getResources().getString(R.string.msgNoConnection),
                AppMsg.STYLE_ALERT);

        noConnectionMsg.setDuration(AppMsg.LENGTH_STICKY);


        connectedMsg = AppMsg.makeText(this,
                getResources().getString(R.string.msgConnected),
                AppMsg.STYLE_INFO);
    }

   ...
   ...

}

But when I run the application, notifications are successfully shown. After cancelling the AppMsgs, App is getting crashed with this Error:

Attempt to invoke virtual method 'boolean com.devspark.appmsg.AppMsg.isShowing()' on a null object reference.

[rcrepaldi]

Only a null check would solve the problem. I see that this library is abandoned by the date of the problem and the neglect of the question. My solution was to download the library and do the null treatment in the class MsgManager.java line: 172