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android-ListView.setAdapter错误:java.lang.NullPointerException_Java_Android_Listview_Nullpointerexception - Fatal编程技术网

android-ListView.setAdapter错误:java.lang.NullPointerException

android-ListView.setAdapter错误:java.lang.NullPointerException,java,android,listview,nullpointerexception,Java,Android,Listview,Nullpointerexception,通过在ListFragment活动中设置适配器,我得到了错误“java.lang.NullPointerException” 这是我的密码: private List<Music> musicList; public View inflate; ListView searchList; public class SearchFragment extends ListFragment { public View onCreateView(LayoutInflater inflater,

通过在ListFragment活动中设置适配器,我得到了错误“java.lang.NullPointerException”

这是我的密码:

private List<Music> musicList;
public View inflate;
ListView searchList;
public class SearchFragment extends ListFragment {
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        context = getActivity().getApplicationContext();
        inflate = inflater.inflate(R.layout.search, container, false);
        musicList = new ArrayList<Music>();
        adapter = new CustomListAdapter(musicList, context);
        searchList.setAdapter(adapter);
}

您已经扩展了
ListFragment
so

setListAdapter(adapter);

看一看

首先,您使用了
ListView searchList
和您尚未初始化的同一个对象,因此在调用
searchList.setAdapter(adapter)时,它会给您NullPointerException


其次,您采用了
ListFragment
,因此可以使用
getListView()
方法直接获取listview。即使您可以直接调用
setListAdapter(adapter)
方法。

尝试此方法,您也会得到NullPointerException,因为您的代码中没有在set adepter之前写入下面的语句。您必须初始化列表视图ListView searchList=(ListView)充气。findViewById(R.id.searchList);
setListAdapter(adapter);