Android使用ListView将数据显示到手机屏幕上

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下面是一个LinearLayout，里面的内容超级简单，就是一个ListView

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <ListView
        android:id="@+id/Lv"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >
    </ListView>

</LinearLayout>

package com.neusoft.ListView.model;

public class Person {
	private String _id;
	private String name;
	private String salary;
	private String phone;

	public Person(String _id, String name, String salary, String phone) {
		super();
		this._id = _id;
		this.name = name;
		this.salary = salary;
		this.phone = phone;
	}

	@Override
	public String toString() {
		return _id + "," + name + "," + salary+ "," + phone;
	}

	public String get_id() {
		return _id;
	}

	public void set_id(String _id) {
		this._id = _id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getSalary() {
		return salary;
	}

	public void setSalary(String salary) {
		this.salary = salary;
	}

	public String getPhone() {
		return phone;
	}

	public void setPhone(String phone) {
		this.phone = phone;
	}

}

package com.neusoft.ListView;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;

public class MyOpenHelper extends SQLiteOpenHelper {

	public MyOpenHelper(Context context) {
		super(context, "people.db", null, 1);
	}
	@Override
	public void onCreate(SQLiteDatabase db) {
		db.execSQL("create table person(_id integer primary key autoincrement,name char(20),salary char(20),phone char(20))");
	}
	@Override
	public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
		System.out.print("数据库升级了");

	}

}

package com.neusoft.ListView;

import java.util.ArrayList;
import java.util.List;
import java.util.zip.Inflater;

import android.os.Bundle;
import android.R.integer;
import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;

import com.neusoft.ListView.model.*;

public class MainActivity extends Activity {
	private ListView Lv;
	List<Person> personList;//创建一个List集合，将所有数据库中每个person加入到此集合中
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		//insert();
		
		
		//从数据库中取出数据
		personList=new ArrayList<Person>();
		MyOpenHelper oh=new MyOpenHelper(this);
		SQLiteDatabase db=oh.getWritableDatabase();

		Cursor cursor=db.query("person",null, null, null, null, null,null);
		while(cursor.moveToNext())
		{
			//循环取出每个person的值
			String _id=cursor.getString(cursor.getColumnIndex("_id"));
			String name=cursor.getString(cursor.getColumnIndex("name"));
			String salary=cursor.getString(cursor.getColumnIndex("salary"));
			String phone=cursor.getString(cursor.getColumnIndex("phone"));
			Person p=new Person(_id, name, salary, phone);
			personList.add(p);//将值加入到集合中
		}
		Lv=(ListView) findViewById(R.id.Lv);
		//将数据显示到屏幕
		Lv.setAdapter(new MyAdapter());
		
	}
	//创建一个内部类MyAdapter，适配器，就是将数据显示到屏幕的工具。
	class MyAdapter extends BaseAdapter
	{

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

		@Override
		public Object getItem(int arg0) {
			// TODO Auto-generated method stub
			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) {
			Person p=personList.get(arg0);
			//第一种写法
//			View view=View.inflate(MainActivity.this,R.layout.item_activity, null);
			//第二种写法
//			LayoutInflater inflater=LayoutInflater.from(MainActivity.this);
//			View view=inflater.inflate(R.layout.item_activity, null);
			
			//第三种写法
//			LayoutInflater inflater2=(LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
//			View view2=inflater2.inflate(R.layout.item_activity, null);
			
			//ListView优化
			View view=null;
			if(arg1==null)//这里是ListView的优化，有了这就话话后，我们就可以把用过了的存入缓存，避免浪费资源
			{
				view=View.inflate(MainActivity.this, R.layout.item_activity, null);
			}
			else
			{
				view=arg1;
			}
			TextView tv_name=(TextView) view.findViewById(R.id.tv_name);
			tv_name.setText(p.getName());
			TextView tv_salary=(TextView) view.findViewById(R.id.tv_salary);
			tv_salary.setText(p.getSalary());
			TextView tv_phone=(TextView) view.findViewById(R.id.tv_phone);
			tv_phone.setText(p.getPhone());
			return view;
		}
		
	}
	//刚开始插入的数据
	public void insert()
	{
		MyOpenHelper oh=new MyOpenHelper(this);
		SQLiteDatabase db=oh.getWritableDatabase();
		for(int i=0;i<100;i++)
		{
			ContentValues values=new ContentValues();
			values.put("name", "张宇翔"+i);
			values.put("salary", "1500"+i);
			values.put("phone","13408"+i);
			db.insert("person", null, values);
		}
	}
}

Android使用ListView将数据显示到手机屏幕上

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原文地址：http://blog.csdn.net/zyx520ytt/article/details/51347586