listView BaseAdpter优化

package com.example.qq_lite.Adpter;import android.content.Context;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.TextView;import com.example.qq_lite.R;import com.example.qq_lite.entity.UserInfoWrapper;import com.example.qq_lite.image.SmartImageView;import java.util.List;import java.util.logging.Handler;/** * Created by linpiaohsin on 2017/11/18. */public class MyAdpter extends BaseAdapter{    List<UserInfoWrapper.UserInfoBean> list;    Context context;    @Override    public int getCount() {        return list.size();    }    public MyAdpter(List<UserInfoWrapper.UserInfoBean> list, Context context) {        this.list = list;        this.context = context;    }    @Override    public Object getItem(int i) {        return list.get(i);    }    @Override    public long getItemId(int i) {        return i;    }    @Override    public View getView(int i, View view, ViewGroup viewGroup) {        Hander hander=new Hander(;        if (view==null){            view= LayoutInflater.from(context).inflate(R.layout.list_item,null);            hander.imageView=view.findViewById(R.id.item_image);            hander.title=view.findViewById(R.id.item_title);            hander.signature=view.findViewById(R.id.item_signature);            view.setTag(hander);        }else view.getTag();        //参数一：请求的url地址，参数2：请求失败的图片；参数三：真正请求的图片        hander.imageView.setImageUrl(list.get(i).getHead(),R.mipmap.ic_launcher_round);        hander.title.setText(list.get(i).getName());        hander.signature.setText(list.get(i).getSignature());        return view;    }    class Hander{        SmartImageView imageView;        TextView title;        TextView signature;    }}