我正在尝试在片段中实现一个列表视图,我使用 BaseAdapter 但我在日志猫上收到错误,这是错误:
10-31 15:41:10.921: E/AndroidRuntime(1246): FATAL EXCEPTION: main
10-31 15:41:10.921: E/AndroidRuntime(1246): java.lang.NullPointerException
10-31 15:41:10.921: E/AndroidRuntime(1246): at info.androidhive.tabsswipe.NewsActivity.onCreateView(NewsActivity.java:28)
...我已经做到了
package info.androidhive.tabsswipe;
import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.GridView;
import android.widget.ListView;
public class NewsActivity extends Fragment{
public ListView liste;
//public GridView grid;
public static Fragment newInstance(Context c){
NewsActivity NA=new NewsActivity();
return NA;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = (View)inflater.inflate(R.layout.fragment_news,container,false);
liste=(ListView)rootView.findViewById(R.id.liste);
liste.setAdapter(new MonAdapter(getActivity()));
return rootView;
}
}
和适配器
package info.androidhive.tabsswipe;
import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
public class MonAdapter extends BaseAdapter {
NewsActivity na=new NewsActivity();
private Context ctx;
private Integer[] vars={
R.drawable.ic_launcher
};
public MonAdapter(Context c){
ctx=c;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return vars.length;
}
@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;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
TextView nom=new TextView(ctx);
TextView prenom=new TextView(ctx);
TextView num=new TextView(ctx);
LinearLayout lt=new LinearLayout(ctx);
lt.setOrientation(LinearLayout.VERTICAL);
LinearLayout l2=new LinearLayout(ctx);
l2.setOrientation(LinearLayout.HORIZONTAL);
nom.setText("AAAA");
prenom.setText("AAAAA");
num.setText("AAAAA");
l2.addView(nom);
l2.addView(prenom);
lt.addView(l2);
lt.addView(num);
return lt;
}
}
作为 getcount 方法的回报,我添加了表变量的长度,因为我在列表视图中有一个元素。