Java Android-Listview保持为空
我目前在片段中实现listview时遇到问题。 我使用了Hashmap,然后将其转换为arrayList,如下所示:Java Android-Listview保持为空,java,android,listview,hashmap,Java,Android,Listview,Hashmap,我目前在片段中实现listview时遇到问题。 我使用了Hashmap,然后将其转换为arrayList,如下所示: public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { final View myView = inflater.inflate( R.layou
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final View myView = inflater.inflate(
R.layout.fragment_portfolio, container, false);
ListView listview = (ListView) myView.findViewById(R.id.listview);
List<HashMap<String, Integer>> fillMaps = new ArrayList<>();
HashMap<String, Integer> portfoliodata = new HashMap<>();
portfoliodata.put("Test", 23);
fillMaps.add(portfoliodata);
SimpleAdapter adapter = new SimpleAdapter(getActivity().getApplicationContext(), fillMaps, R.layout.my_adapter_item, new String[] { "AAA","BBB" },
new int[] { android.R.id.text1, android.R.id.text2 });
listview.setAdapter(adapter);
return myView;
}
public View onCreateView(布局、充气机、视图组容器、,
Bundle savedInstanceState){
最终视图myView=充气机。充气(
R.layout.fragment_公文包,容器,假);
ListView ListView=(ListView)myView.findViewById(R.id.ListView);
List fillMaps=new ArrayList();
HashMap portfoliodata=新HashMap();
portfoliodata.put(“测试”,23);
添加(portfoliodata);
SimpleAdapter=new SimpleAdapter(getActivity().getApplicationContext(),fillMaps,R.layout.my_adapter_项,新字符串[]{“AAA”,“BBB”},
新的int[]{android.R.id.text1,android.R.id.text2});
setAdapter(适配器);
返回myView;
}
然而,结果总是一片空白。你知道为什么会这样做吗?我怎样才能解决这个问题
提前感谢getActivity()在方法onCreateView()中不存在,因为您还没有活动的上下文
您可以探测将代码移动到onResume()方法
*请记住,您必须将每一列与数据连接起来,类似于:
ListView listview;
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View myView = inflater.inflate(
R.layout.fragment_portfolio, container, false);
listview = (ListView) myView.findViewById(R.id.listview);
return myView;
}
@Override
public void onResume() {
// create the grid item mapping
String[] from = new String[] {"AAA","BBB"};
int[] to = new int[] {android.R.id.text1, android.R.id.text2};
List<HashMap<String, String>> fillMaps = new ArrayList<>();
HashMap<String, String> portfoliodata = new HashMap<>();
portfoliodata.put("AAA", "Text SampleA");
portfoliodata.put("BBB", "Text SampleB");
fillMaps.add(portfoliodata);
SimpleAdapter adapter = new SimpleAdapter(getActivity(), fillMaps,
R.layout.my_adapter_item, from, to);
listview.setAdapter(adapter);
}
ListView-ListView;
创建视图上的公共视图(布局、充气机、视图组容器、,
Bundle savedInstanceState){
查看myView=充气机。充气(
R.layout.fragment_公文包,容器,假);
listview=(listview)myView.findViewById(R.id.listview);
返回myView;
}
@凌驾
恢复时公开作废(){
//创建网格项映射
字符串[]from=新字符串[]{“AAA”,“BBB”};
int[]to=newint[]{android.R.id.text1,android.R.id.text2};
List fillMaps=new ArrayList();
HashMap portfoliodata=新HashMap();
portfoliodata.put(“AAA”,“文本SAMA”);
portfoliodata.put(“BBB”,“文本样本”);
添加(portfoliodata);
SimpleAdapter=新SimpleAdapter(getActivity(),fillMaps,
R.layout.my_适配器_项,从,到);
setAdapter(适配器);
}
祝你好运 发布R.layout.my_adapter_item.xml的内容在listview行布局中是否有android.R.id.text1、android.R.id.text2