使用BaseAdapter的Android-自定义列表视图不显示任何内容

Question

有类似的问题，但解决方案都没有帮助。我认为问题在于布局文件或适配器类但无法找到错误。 Fragment加载正常，但列表视图中没有任何内容。

FavouritesFragment.java

import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.ListActivity;
import android.content.ContentResolver;
import android.database.Cursor;
import android.os.Bundle;
import android.provider.ContactsContract;
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 FavoritesFragment extends android.app.Fragment {




String namearray[];
String phonearray[];
String namecsv;
String phonecsv;
ListView lvl;
public static FavoritesFragment newInstance()
{
    FavoritesFragment fragment = new FavoritesFragment();
    return fragment;
}

public FavoritesFragment() {}

@Override
public void onAttach(Activity activity) {
    // TODO Auto-generated method stub
    super.onAttach(activity);
    ((NavigationActivity) activity).onSectionAttached(4);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    View rootView = inflater.inflate(R.layout.favorites, container, false);

    lvl = (ListView) rootView.findViewById(R.id.listViewFavourite);

    Cursor phones = getActivity().getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI,null,null,null, null);
    while(phones.moveToNext())
    {
        //read contact name
        String name = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));

        //read contact phonenumber
        String phoneNumber = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));

      if(name!=null)
      {
          namecsv += name +",";
          phonecsv+=phoneNumber +",";
      }

    }

    phones.close();

    namearray = namecsv.split(",");
    phonearray= phonecsv.split(",");

    namearray = removeDuplicate(namearray);
    phonearray = removeDuplicate(phonearray);


    // ListAdapter theAdapter = new ArrayAdapter<>(getActivity(),android.R.layout.simple_list_item_1, namearray);
    ListAdapter theAdapter = new FavouriteAdapter(getActivity(), namearray, phonearray);

    lvl.setAdapter(theAdapter);
    Toast.makeText(getActivity(),namecsv, Toast.LENGTH_SHORT).show();

    lvl.setOnItemClickListener(new AdapterView.OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {
            // TODO Auto-generated method stub
            String number = String.valueOf(parent.getItemAtPosition(position));
            Toast.makeText(getActivity(), number, Toast.LENGTH_SHORT).show();
        }


    });
    return rootView;
}



public String[] removeDuplicate(String[] str)
{
    List<String> list = Arrays.asList(str);
    Set<String> set = new HashSet<String>(list);
    String[] res = new String[set.size()];
    set.toArray(res);
    return res;
}
@Override
public void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);



}


}

favourites.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >

<ListView
    android:id="@+id/listViewFavourite"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >
</ListView>

rowlayoutfavurite.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<TextView
    android:id="@+id/textViewContactName"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:padding="@dimen/padding"
    android:text="Medium Text"
    android:textAppearance="?android:attr/textAppearanceMedium"
    android:textColor="#000000"
    android:textStyle="bold" />

<TextView
    android:id="@+id/textViewPhoneNumber"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:paddingLeft="10dp"
    android:text="Text View"
     />

 </LinearLayout>

FavouriteAdapter.java

import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.BaseAdapter;
import android.widget.TextView;

public class FavouriteAdapter extends BaseAdapter {

String[] name;
String[] phone;
Context context;

  public FavouriteAdapter(Context cntxt, String[] valuename, String[] phonevalue)
  {
  super();
   name = valuename;
   phone=phonevalue;
   context = cntxt;

  }

@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub

LayoutInflater inflator = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

View theView = inflator.inflate(R.layout.rowlayoutfavorite, parent, false);

TextView nameTextView = (TextView) theView.findViewById(R.id.textViewContactName);
TextView numberTextView = (TextView) theView.findViewById(R.id.textViewPhoneNumber);
nameTextView.setText(name[position].toString());
numberTextView.setText(phone[position].toString());
return theView;
}

@Override
public int getCount() {
// TODO Auto-generated method stub
return 0;
}

@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return null;
}

@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}



}

Answer 1

问题是由getCount()的实施引起的。负责在屏幕上显示列表的某个部分调用此方法。当你返回零时，列表似乎是空的，就是这样。

更改方法：

@Override
public int getCount() 
{
    return name.length;
}