Android listView 中响应Button点击事件

public class Task_list_single_item_adapter extends BaseAdapter{LayoutInflater inflater;Context context;public Task_list_single_item_adapter(Context context){this.context=context;inflater=LayoutInflater.from(context);}@Overridepublic int getCount(){return 2;}@Overridepublic Object getItem(int position){return null;}@Overridepublic long getItemId(int position){return position;}@Overridepublic View getView(int position, View convertView, ViewGroup parent){final Holder holder;if(convertView!=null){holder=(Holder) convertView.getTag();}else {holder=new Holder();convertView=inflater.inflate(R.layout.download_management_item, null);holder.pause=(Button) convertView.findViewById(R.id.dmi_ib1_pause);holder.trys=(Button) convertView.findViewById(R.id.dmi_ib2_recover);holder.install=(Button) convertView.findViewById(R.id.dmi_ib3_install);convertView.setTag(holder);}OnClickListener listener=new OnClickListener(){@Overridepublic void onClick(View v){if(v==holder.pause){Toast.makeText(context, "pause", Toast.LENGTH_SHORT).show();holder.pause.setVisibility(View.GONE);holder.trys.setVisibility(View.VISIBLE);holder.install.setVisibility(View.GONE);}if(v==holder.trys){Toast.makeText(context, "try", Toast.LENGTH_SHORT).show();holder.pause.setVisibility(View.VISIBLE);holder.trys.setVisibility(View.GONE);holder.install.setVisibility(View.GONE);}if(v==holder.install)Toast.makeText(context, "install", Toast.LENGTH_SHORT).show();}};holder.pause.setOnClickListener(listener);holder.trys.setOnClickListener(listener);holder.install.setOnClickListener(listener);return convertView;}class Holder{public Button pause;public Button trys;public Button install;}}