38.Android之ListView简单学习(一)

android中ListView用的很普遍，今天来学习下，本篇主要以本地数据加载到listview,后面会学习从网络获取数据添加到listview。

首先改下布局文件：

<?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="vertical" >

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

SimpleAdapter对应布局文件：

<?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="vertical" >
    
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical" >

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="50dp" >

            <LinearLayout
                android:layout_width="wrap_content"
                android:layout_height="match_parent"
                android:orientation="vertical" >

                <ImageView
                    android:id="@+id/img"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" />
            </LinearLayout>

            <LinearLayout
                android:layout_width="wrap_content"
                android:layout_height="match_parent"
                android:layout_weight="1"
                android:orientation="vertical" >

                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:orientation="vertical" >

                    <TextView
                        android:id="@+id/appnametext"
                        android:layout_width="wrap_content"
                        android:layout_height="match_parent"
                        android:gravity="center"
                        android:text="weixin" />
                </LinearLayout>

                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:orientation="horizontal" >

                    <TextView
                        android:id="@+id/sizetext"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_gravity="center"
                        android:text="15.23" />

                    <View
                        android:layout_width="1dp"
                        android:layout_height="match_parent"
                        android:layout_marginBottom="5dp"
                        android:layout_marginLeft="7dp"
                        android:layout_marginRight="3dp"
                        android:layout_marginTop="5dp"
                        android:background="#000000" />

                    <TextView
                        android:id="@+id/amounttext"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_gravity="center"
                        android:layout_marginLeft="2dp"
                        android:text="1234567" />
                </LinearLayout>
            </LinearLayout>

            <LinearLayout
                android:layout_width="wrap_content"
                android:layout_height="match_parent"
                android:orientation="vertical" >

                <Button
                    android:id="@+id/dowmbutton"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_marginLeft="5dp"
                    android:layout_marginRight="10dp"
                    android:text="load" />
            </LinearLayout>
        </LinearLayout>
    </LinearLayout>
    

</LinearLayout>

修改下MainActivity.java文件：

package com.example.listviewdemo1;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.ListAdapter;
import android.widget.SimpleAdapter;
import android.widget.TextView;

public class MainActivity extends Activity {

    private ListView listView;
    private Intent intent;
    private List<Map<String, Object>> mData;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        listView = (ListView) findViewById(R.id.listview);
        SimpleAdapter simpleAdapter = new SimpleAdapter(this, getData(),
                R.layout.simp_adap, new String[] { "nametext", "teitext",
                        "amounttext" }, new int[] { R.id.appnametext,
                        R.id.sizetext, R.id.amounttext });
        listView.setAdapter(simpleAdapter);
        mData = getData();
        MyAdapter adapter = new MyAdapter(this);
        listView.setAdapter(adapter);

    }

    public 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("appnametext", "微信");
        map.put("sizetext", "15.2");
        map.put("amounttext", "1234323");
        map.put("appimg", R.drawable.weixin);
        list.add(map);

        map = new HashMap<String, Object>();
        map.put("appnametext", "手机QQ");
        map.put("sizetext", "8.5");
        map.put("amounttext", "122073323");
        map.put("appimg", R.drawable.qq);
        list.add(map);

        map = new HashMap<String, Object>();
        map.put("appnametext", "手机QQ空间");
        map.put("sizetext", "6.3");
        map.put("amounttext", "122393");
        map.put("appimg", R.drawable.qqko);
        list.add(map);

        map = new HashMap<String, Object>();
        map.put("appnametext", "微博");
        map.put("sizetext", "7.7");
        map.put("amounttext", "1278323");
        map.put("appimg", R.drawable.weib);
        list.add(map);

        map = new HashMap<String, Object>();
        map.put("appnametext", "陌陌");
        map.put("sizetext", "6.9");
        map.put("amounttext", "1279073");
        map.put("appimg", R.drawable.mom);
        list.add(map);

        map = new HashMap<String, Object>();
        map.put("appnametext", "飞信");
        map.put("sizetext", "6.9");
        map.put("amounttext", "1279073");
        map.put("appimg", R.drawable.fei);
        list.add(map);
        return list;
    }

    public final class ViewHolder {
        public ImageView appimg;
        public TextView appnametext;
        public TextView sizetext;
        public TextView amounttext;
        public Button dowmbutton;
    }

    public class MyAdapter extends BaseAdapter {

        private LayoutInflater mInflater;

        public MyAdapter(Context context) {
            this.mInflater = LayoutInflater.from(context);
        }

        @Override
        public int getCount() {
            return mData.size();
        }

        @Override
        public Object getItem(int arg0) {
            return null;
        }

        @Override
        public long getItemId(int arg0) {
            // TODO Auto-generated method stub
            return 0;
        }

        @Override
        public View getView(int arg0, View arg1, ViewGroup arg2) {
            // TODO Auto-generated method stub
            ViewHolder holder = null;
            if (arg1 == null) {
                holder = new ViewHolder();
                arg1 = mInflater.inflate(R.layout.simp_adap,null);
                holder.appimg = (ImageView) arg1.findViewById(R.id.img);
                holder.appnametext = (TextView) arg1.findViewById(R.id.appnametext);
                holder.sizetext = (TextView) arg1.findViewById(R.id.sizetext);
                holder.amounttext = (TextView) arg1.findViewById(R.id.amounttext);
                holder.dowmbutton = (Button) arg1.findViewById(R.id.dowmbutton);
                arg1.setTag(holder);
            } else {
                holder = (ViewHolder) arg1.getTag();
            }

            holder.appimg.setBackgroundResource((Integer) mData.get(arg0).get("appimg"));
            holder.appnametext.setText((String) mData.get(arg0).get("appnametext"));
            holder.sizetext.setText((String) mData.get(arg0).get("sizetext"));
            holder.amounttext.setText((String) mData.get(arg0).get("amounttext"));

            return arg1;
        }

    }

}

运行效果：