SimpleAdapter 的用法及点击事件中如何获取选中项的值

       SimpleAdapter的使用步骤及点击事件中如何获取选中项的值:

       一、首先我们需要先写一个布局文件item.xml,代码如下:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal">

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/pic"
        />
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/text"
        android:textSize="25sp"
        android:layout_gravity="center_vertical"
        android:layout_marginLeft="10dp"
        />

</LinearLayout>
二、创建新的布局文件layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ListView
        android:id="@+id/listview"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</LinearLayout>

三、

(SimpleAdapter)数据适配器的实现过程:

1.新建适配器
simp_adapter=new SimpleAdapter<String>(context,data,resource,from,to);
context:上下文(this)
data:有特定泛型的集合数据源--一个Map所组成的List集合
(新建自定义List<Map<String,Object>> dataList并通过方法返回在此处)
<每一个Map都会去对应列表中的一行,每一个Map中的键必须包含所有在from中所指定的键>
resource:列表项的布局文件(自定义布局)
from:记录Map中的键名(new String[]{布局文件的name})
to:绑定数据视图中的ID,与from成对应关系(new int[]{布局文件中ID})
2.添加数据源到适配器(上一步已包含)
3.视图(ListView)加载适配器
listView.setAdapter(simp_adapter);

4.数据源getdata();
 private List<Map<String, Object>> getdata() {
        List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("pic", R.drawable.apple_pic);
        map.put("text", "apple");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.pear_pic);
        map.put("text", "pear");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.watermelon_pic);
        map.put("text", "watermelon");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.cherry_pic);
        map.put("text", "cherry");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.strawberry_pic);
        map.put("text", "strawberry");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.grape_pic);
        map.put("text", "grape");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.orange_pic);
        map.put("text", "orange");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.mango_pic);
        map.put("text", "mango");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.pineapple_pic);
        map.put("text", "pineapple");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.banana_pic);
        map.put("text", "banana");
        list.add(map);
        return list;
    }
5.添加点击事件监听,获取选中项的值
    public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
        /*adapterView是指当前的listview;
         *view是当前listview中的item的view的布局,就是可用这个view获取里面控件id后操作控件
         * i是当前item在listview中适配器的位置
         * l是当前item在listview里第几行的位置
         */
        //获得选中项中的HashMap对象
        HashMap<String,String> map=(HashMap<String,String>)adapterView.getItemAtPosition(i);
        String Text=map.get("text");
        Toast.makeText(MainActivity.this,Text,Toast.LENGTH_SHORT).show();
    }

四、运行效果图

点击了apple选项:

   


点击了watermelon选项:
                  
   

实现过程代码如下:
package com.example.administrator.mydivlistview;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SimpleAdapter;
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 implements AdapterView.OnItemClickListener{
    private ListView listview;
    private SimpleAdapter sim_adapter;
    private TextView text;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout);
        text=(TextView) findViewById(R.id.text);
        listview = (ListView) findViewById(R.id.listview);
        sim_adapter = new SimpleAdapter(this, getdata(), R.layout.item, new String[]{"pic", "text"}, new int[]{R.id.pic, R.id.text});
        listview.setAdapter(sim_adapter);
        listview.setOnItemClickListener(this);
    }

    private List<Map<String, Object>> getdata() {
        List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("pic", R.drawable.apple_pic);
        map.put("text", "apple");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.pear_pic);
        map.put("text", "pear");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.watermelon_pic);
        map.put("text", "watermelon");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.cherry_pic);
        map.put("text", "cherry");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.strawberry_pic);
        map.put("text", "strawberry");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.grape_pic);
        map.put("text", "grape");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.orange_pic);
        map.put("text", "orange");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.mango_pic);
        map.put("text", "mango");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.pineapple_pic);
        map.put("text", "pineapple");
        list.add(map);
        map = new HashMap<String, Object>();
        map.put("pic", R.drawable.banana_pic);
        map.put("text", "banana");
        list.add(map);
        return list;
    }

    @Override
    public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
        /*adapterView是指当前的listview;
         *view是当前listview中的item的view的布局,就是可用这个view获取里面控件id后操作控件
         * i是当前item在listview中适配器的位置
         * l是当前item在listview里第几行的位置
         */
        //获得选中项中的HashMap对象
        HashMap<String,String> map=(HashMap<String,String>)adapterView.getItemAtPosition(i);
        String Text=map.get("text");
        Toast.makeText(MainActivity.this,Text,Toast.LENGTH_SHORT).show();
    }
}



猜你喜欢

转载自blog.csdn.net/Best_CXY/article/details/62231066