ListView

package com.zyeq.cxsw.listview_3;
import android.graphics.Color;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class MainActivity extends AppCompatActivity {
    private int[] ids={R.drawable.img_1,R.drawable.img_2,R.drawable.img_3,R.drawable.img_4,R.drawable.img_5,R.drawable.img_6,R.drawable.img_7,R.drawable.img_8,R.drawable.img_9,R.drawable.img_10};
    private ListView listView;
    private List<Map<String, String>> data = new ArrayList<>();
    private int temp;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        listView = (ListView) this.findViewById(R.id.listView);

        /*加载数据*/
        data=loadData();
        /*创建适配器*/
        MyAdapter adapter=new MyAdapter();
        /*设置适配器*/
        listView.setAdapter(adapter);
    }

    /*使用BasicAdapter*/
    class MyAdapter extends BaseAdapter {

        /*返回数据的条数*/
        @Override
        public int getCount() {
            return data.size();
        }

        /*返回一个对象*/
        @Override
        public Object getItem(int position) {
            return null;
        }

        /*返回代表当前item项的id*/
        @Override
        public long getItemId(int position) {
            return position;
        }
        /**/
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            temp=position;
            /*将布局转化为一个View对象*/
            /*1.获取布局加载器*/
            /*ListView的优化操作：1.复用布局 2.减少findViewById的次数
            * */
            View view=convertView;
            ViewHolder viewHolder;
            if(view==null){
                view = getLayoutInflater().inflate(R.layout.list_item, parent, false);
                  /*从布局文件中获取UI控件*/
                viewHolder=new ViewHolder();
                TextView textView= (TextView) view.findViewById(R.id.name);
                ImageView imageView= (ImageView) view.findViewById(R.id.logo);
                viewHolder.setImageView(imageView);
                viewHolder.setTextView(textView);
                view.setTag(viewHolder);
            }
            viewHolder= (ViewHolder) view.getTag();
            viewHolder.getTextView().setText(data.get(position).get("name"));
            /*为图片设置监听器*/
            viewHolder.getImageView().setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Toast.makeText(getApplicationContext(), "id:" + data.get(temp).get("logo"), Toast.LENGTH_SHORT).show();
                }
            });
            /*设置字体的颜色*/
            if(position==9){
                viewHolder.getTextView().setTextColor(Color.RED);
            }
            viewHolder.getImageView().setImageResource(Integer.parseInt(data.get(position).get("logo")));
            return view;
        }
        /*封装控件*/
        class ViewHolder{
            private TextView textView;
            private ImageView imageView;

            public TextView getTextView() {
                return textView;
            }

            public void setTextView(TextView textView) {
                this.textView = textView;
            }

            public ImageView getImageView() {
                return imageView;
            }

            public void setImageView(ImageView imageView) {
                this.imageView = imageView;
            }
        }
    }
    /*需要的数据源*/
    public List<Map<String, String>> loadData() {
        List<Map<String, String>> list = new ArrayList<>();
        Map<String, String> map = null;
        for (int i = 1; i <= 1000; i++) {
            map=new HashMap<>();
            map.put("name", "user" + i);
            map.put("logo",""+ids[i%10]);
            list.add(map);
        }
        return list;
    }
}