Android 列表视图刷新 - notifyDataSetChanged() 选项不可用
Android Listview refreshing - notifyDataSetChanged() option not available
我有一个带有 tablayout 的片段(里面有 2 个选项卡)和一个由 .xml 文件中的字符串项填充的列表视图。我想在单击选项卡时更改 .xml 资源文件,但列表视图没有更改。我发现很多答案都说我应该使用 notifyDataSetChanged() 但我在键入适配器时没有将其作为选项。 (没有自动完成选项)
这是我的代码
import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.Toast;
public class IMFragment extends Fragment {
private TabLayout tl;
private String[] sM;
private String s="x1";
public IMFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_im, container, false);
tl = v.findViewById(R.id.tlID);
tl.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
s=tab.getText().toString();
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {}
@Override
public void onTabReselected(TabLayout.Tab tab) {}
});
switch (s) {
case "x1":
sM = getResources().getStringArray(R.array.x1);
break;
case "x2":
sM = getResources().getStringArray(R.array.x2);
break;
}
ListView iMLV = v.findViewById(R.id.im_lvID);
ListAdapter mListAdapter = new ArrayAdapter<>(getActivity(), android.R.layout.simple_list_item_1, sM);
iMLV.setAdapter(mListAdapter);
return v;
}
}
如果您更新当前 ArrayAdapter
,则不需要 notifyDataSetChanged
public void onTabSelected(TabLayout.Tab tab) {
s=tab.getText().toString();
ArrayAdapter adapter = (ArrayAdapter) iMLV.getAdapter()
adapter.clear();
adapter.addAll(Arrays.asList(getResources().getStringArray(R.array.x2))) // adapt code here to inject right array list
}
我有一个带有 tablayout 的片段(里面有 2 个选项卡)和一个由 .xml 文件中的字符串项填充的列表视图。我想在单击选项卡时更改 .xml 资源文件,但列表视图没有更改。我发现很多答案都说我应该使用 notifyDataSetChanged() 但我在键入适配器时没有将其作为选项。 (没有自动完成选项)
这是我的代码
import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.Toast;
public class IMFragment extends Fragment {
private TabLayout tl;
private String[] sM;
private String s="x1";
public IMFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_im, container, false);
tl = v.findViewById(R.id.tlID);
tl.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
s=tab.getText().toString();
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {}
@Override
public void onTabReselected(TabLayout.Tab tab) {}
});
switch (s) {
case "x1":
sM = getResources().getStringArray(R.array.x1);
break;
case "x2":
sM = getResources().getStringArray(R.array.x2);
break;
}
ListView iMLV = v.findViewById(R.id.im_lvID);
ListAdapter mListAdapter = new ArrayAdapter<>(getActivity(), android.R.layout.simple_list_item_1, sM);
iMLV.setAdapter(mListAdapter);
return v;
}
}
如果您更新当前 ArrayAdapter
notifyDataSetChanged
public void onTabSelected(TabLayout.Tab tab) {
s=tab.getText().toString();
ArrayAdapter adapter = (ArrayAdapter) iMLV.getAdapter()
adapter.clear();
adapter.addAll(Arrays.asList(getResources().getStringArray(R.array.x2))) // adapt code here to inject right array list
}