一个进步，它的工作原理

A step forward and it works

public class ListViewA extends Activity {
GridView MyGrid;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    MyGrid = (GridView) findViewById(R.id.gridview);
    MyGrid.setAdapter(new ImageAdapter(this));
}

public class ImageAdapter extends BaseAdapter {
    Context MyContext;

    public ImageAdapter(Context _MyContext) {
        MyContext = _MyContext;
    }

    @Override
    public int getCount() {
        return 9;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        View view = convertView;

        if (convertView == null) {

            LayoutInflater li = getLayoutInflater();
            view = li.inflate(R.layout.main, null);
        }

        if (position % 2 == 0)
            view.setBackgroundColor(0x30FF0000);
        else
            view.setBackgroundColor(0x300000FF);
        return view;

    }

    @Override
    public Object getItem(int arg0) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public long getItemId(int arg0) {
        // TODO Auto-generated method stub
        return 0;
    }
}

}