App crash with Null Object Reference I am using a AutoCompleteTextView in a Fragment... but when I use a method which refreshes the Suggestions for AutoCompleteTextView, the App crashes with Null Object Reference here's the method -   private ArrayList&lt;String&gt; sugs = new ArrayList&lt;String&gt;();  public void refreshSugs()  {     ((AutoCompleteTextView) getView().findViewById(R.id.editText1)).setAdapter(new ArrayAdapter(getActivity(), 17367050, this.sugs)); }  @Override public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState)  {     //Inflating the Layout      View rootView = inflater.inflate(R.layout.home_fragment, container, false);       Button buttongo = (Button) rootView.findViewById(R.id.button1);     EditText et1 = (EditText) rootView.findViewById(R.id.editText1);     Button buttonsave = (Button) rootView.findViewById(R.id.button2);       bar = (ProgressWheel) rootView.findViewById(R.id.progressBar1);     i = (ImageView) rootView.findViewById(R.id.imageView1);     background2 = (TextView) rootView.findViewById(R.id.textView1);     background3 = (TextView) rootView.findViewById(R.id.textView2);     readSugs();     refreshSugs();      return rootView; }
What is a NullPointerException, and how do I fix it? What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?
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