这个问题在这里已有答案:
list = (ListView) findViewById( R.id.simple_list );
String[] planets = new String[] { "Mercury", "Venus", "Earth", "Mars",
"Jupiter", "Saturn", "Uranus", "Neptune"};
ArrayList<String> planetList = new ArrayList<String>();
planetList.addAll( Arrays.asList(planets) );
// Create ArrayAdapter using the planet list.
listAdapter = new ArrayAdapter<String>(getApplicationContext(), R.layout.food_menu, planetList);
// Set the ArrayAdapter as the ListView's adapter.
list.setAdapter( listAdapter );
它说的错误在底线
java.lang.RuntimeException:无法启动活动ComponentInfo {com.example.grantjones20.restaurant/com.example.grantjones20.restaurant.MainActivity}:java.lang.NullPointerException:尝试调用虚方法'void android.widget.ListView .setAdapter(android.widget.ListAdapter)'对空对象引用