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POCan't understand NullPointerException
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  1. POCan't understand NullPointerException
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    copied!<p>I'm experimenting with ListViews and ArrayAdapters, and i've come into a runTimeException issue, the DDMS error report is telling me that i'm having a NullPointerException at the line containing "public void onItemClick", I cant see why it is giving me a issue.</p> <pre><code> package com.example.worksheet2; import android.os.Bundle; import android.app.ListActivity; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.ArrayAdapter; import android.widget.ListView; import android.widget.Toast; public class MainActivity extends ListActivity { ListView listview; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); ListView listview = (ListView) findViewById(R.layout.activity_main); String[] values = { "A", "B", "C" }; ArrayAdapter&lt;String&gt; adapter = new ArrayAdapter&lt;String&gt;(this, R.id.menu_settings, values); // asign adapter to listview listview.setAdapter(adapter); listview.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView&lt;?&gt; parent, View v, int position, long id) { Toast.makeText(getApplicationContext(), "Click ListItem Number " + position, Toast.LENGTH_LONG) .show(); } }); } } </code></pre> <p>Here's the error report</p> <pre><code> Caused by: java.lang.NullPointerException at com.example.worksheet2.MainActivity.onCreate(MainActivity.java:31) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1072) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1836) </code></pre>
 

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