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:

38.Android之ListView简单学习(一)

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