返回gridview里选中的Button上面的文字到外面的TextView

Question

public class Gridview2Adapter  extends BaseAdapter {
public Gridview2Adapter(Context context,List<String> list)
{

}
@Override
public int getCount() {
// TODO Auto-generated method stub
return 20;//按钮的个数
}

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

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

@Override
public View getView(int position, View convertview, ViewGroup arg2) {
convertview=inflater.inflate(R.layout.gridview2_item, null);
g2_btn=(Button) convertview.findViewById(R.id.g2_btn);

//List<String> band=setChannel_band();
//给每一个button设置监听事件，即是让textview的内容显示为点击的按钮上的text作为频道
String str=(String)g2_btn.getText();
channel.setText(str);


return convertview;
}
}

public class MainActivity extends Activity {
    GridView gridview2;
    TextView channel;
    List<String> channel_band=new ArrayList<String>();
    //设置按钮默认的文字
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        gridview2=(GridView)findViewById(R.id.gridview2);
        gridview2.setAdapter(new Gridview2Adapter(this,channel_band));

        channel=(TextView) findViewById(R.id.channel);
        for(int j=0;j<19;j++){
        channel_band.add("频道"+j);
        }
        gridview2.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position,
        long id) {
        // TODO Auto-generated method stub
            for(int i = 0;i<channel_band.size();i++){
                if(position == i){
                    channel_band.get(i).setSelect(true);
                }else{
                    channel_band.get(i).setSelect(false);
                }
            }
            mAdapter.choiceState(position);
        Toast.makeText(MainActivity.this, position+"被点击", Toast.LENGTH_SHORT).show();
        }
        });



    }

越想越乱，不知道怎么写了