在自定义适配器中传递arrayList

Question

I am calling an Arraylist in a CustomAdapter, with custom_row.xml which contains the desired row. I want first two elements of the arraylist side by side in a row, and then third and fourth element in the other row and so on. I wrote this code, just to print the first element from the Arraylist. if I remove the comments and then run, I get the same error as when putting comments. I don't know where I am going wrong.

or maybe what should be the right way.

class CustomAdapter extends ArrayAdapter {

List<String> names;
LayoutInflater inflater;
Context context;
public CustomAdapter(Context context,  List<String> names) {
    super(context,R.layout.custom_row ,names);
   this.names=names;
    this.context=context;
}


@Override
public View getView(int position, View convertView, ViewGroup parent) {


   inflater=LayoutInflater.from(getContext());
    View customview=inflater.inflate(R.layout.custom_row,parent,false);
    String data=names.get(position);
   //String data1=names.get(position+1);
    TextView tv=(TextView)customview.findViewById(R.id.TeamA);
    tv.setText(data);
   //TextView tv1=(TextView)customview.findViewById(R.id.TeamB);
    //tv1.setText(data1);
    return customview;
}

I am getting this error- java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference at com.example.CustomAdapter.getView

Answer 1

问题是因为tv为null，即因为findViewById(R.id.TeamA)返回null，所以..检查TeamA存在于R.layout.custom_row