Question

我有一个片段类，在单击选项卡时会调用它。将数据插入数据库后，片段中的listview不会自动刷新。列表视图仅在重新打开应用程序时刷新，或仅在切换其他选项卡后才打开当前选项卡。帮我自动刷新当前片段的列表视图。

SocialFragment.java

        package layout;
        import android.content.Context;
        import android.database.Cursor;
        import android.os.Bundle;
        import android.support.annotation.Nullable;
        import android.support.v4.app.Fragment;
        import android.view.LayoutInflater;
        import android.view.View;
        import android.view.ViewGroup;
        import android.widget.BaseAdapter;
        import android.widget.ListView;
        import android.widget.SimpleCursorAdapter;
        import android.widget.TextView;

        import com.example.kiran.herau.NewDatabaseAdapter;
        import com.example.kiran.herau.R;


public class SocialFragment extends Fragment {

    protected BaseAdapter mAdapter;
    private SimpleCursorAdapter dataAdapter;
    NewDatabaseAdapter vivzHelper;
    TextView text;

    Context context;

    @Nullable

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
        View view = inflater.inflate(R.layout.activity_fifth, null);

ListView lb = (ListView)view.findViewById(R.id.listView1);
        context = getActivity().getBaseContext();
        vivzHelper = new NewDatabaseAdapter(getActivity());
        Cursor cursor = vivzHelper.fetchAllData();

        // The desired columns to be bound
        String[] columns = new String[]{

                NewDatabaseAdapter.NewDatabaseHelper.UID,
                NewDatabaseAdapter.NewDatabaseHelper.TEACHER_NAME,
                NewDatabaseAdapter.NewDatabaseHelper.SUBJECT_NAME,
                NewDatabaseAdapter.NewDatabaseHelper.START_TIME,
                NewDatabaseAdapter.NewDatabaseHelper.END_TIME,

        };

        // the XML defined views which the data will be bound to
        int[] to = new int[]{
                R.id.uid,
                R.id.date,
                R.id.time,
                R.id.subject,
                R.id.end_time,
        };

        // create the adapter using the cursor pointing to the desired data
        //as well as the layout information

        dataAdapter = new SimpleCursorAdapter(
                context, R.layout.routinerow,
                cursor,
                columns,
                to,
                0);

        lb.setEmptyView(view.findViewById(R.id.empty));
        dataAdapter.notifyDataSetChanged();
        // Assign adapter to ListView
        lb.setAdapter(dataAdapter);

        return view;
    }

}

Answer 1

如果您有代码告诉您数据库何时更新，您只需调用

即可

adapter.notifyDataSetChanged();

喜欢 -

public void methodThatIsCalledWhenDatabaseUpdates(Datatype data){
     adapter.setData(data);
     adapter.notifyDataSetChanged();
}

在数据库中插入数据时，在片段中自动刷新ListView

1 个答案: