ListView显示Sqlite的数据

在安卓中，ListView和Sqlite都是十分常用的。这次我们来结合这个两个知识点写一个Demo。

功能：吧SQLite中的数据用ListView显示出来。

先看截图吧

首先是数据库

然后是运行截图

接下来是讲解，运行程序后，先点击创建数据库的按钮，会创建出50条数据，然后点击查询，会将这50条数据查询并显示在ListView中。

直接看代码吧！

布局文件activity_main.xml　　　

<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"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.listviewdemo.MainActivity" >

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:onClick="Create_Data"
        android:text="创建数据" />

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:onClick="Query_Data"
        android:text="查询数据" />

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

</LinearLayout>

java文件

Girl.java

作为javabean，存储数据类用的

package com.example.listviewdemo;

public class Girl {

    private String name;
    private int age;
    private String phone;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getPhone() {
        return phone;
    }
    public void setPhone(String phone) {
        this.phone = phone;
    }
    @Override
    public String toString() {
        return name+","+age+","+phone;
    }
    public Girl(String name, int age, String phone) {
        super();
        this.name = name;
        this.age = age;
        this.phone = phone;
    }

}

MainActivity.java

package com.example.listviewdemo;

import java.util.ArrayList;
import java.util.List;

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

public class MainActivity extends Activity {

    private MyOpenSqlHelp myDatebaseHelper;
     List<Girl> girList ;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        myDatebaseHelper = new MyOpenSqlHelp(this, "People.db", null, 1);
        SQLiteDatabase db = myDatebaseHelper.getWritableDatabase();
        girList = new ArrayList<Girl>();
    }

    public void Create_Data(View v) {
         SQLiteDatabase db = myDatebaseHelper.getWritableDatabase();

         for(int i=0;i<=50;i++){
             ContentValues values = new ContentValues();
             values.put("Name", "朱主爱"+i);
             values.put("Age", "19");
             values.put("Phone", "135708"+i);
             db.insert("Girl", null, values);
         }
         Toast.makeText(this, "数据创建成功", 0).show();
    }

    public void Query_Data(View v) {
         SQLiteDatabase db = myDatebaseHelper.getWritableDatabase();
         Cursor cursor = db.query("Girl", null, null, null, null, null, null);

         while (cursor.moveToNext()) {

             String name = cursor.getString(cursor.getColumnIndex("Name"));
             int age = cursor.getInt(cursor.getColumnIndex("Age"));
             String phone = cursor.getString(cursor.getColumnIndex("Phone"));

             Girl girl =new Girl(name,age,phone);
             girList.add(girl);

        }
         //拿到listveiw对象
        ListView lv = (ListView) findViewById(R.id.lv);
        //设置适配器
        lv.setAdapter(new MyAapter());

    }
  //适配器类
    class MyAapter extends BaseAdapter {

        //获取集合中有多少条元素,由系统调用
        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return girList.size();
        }

        @Override
        public Object getItem(int position) {
            // TODO Auto-generated method stub
            return null;
        }

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

        //由系统调用，返回一个view对象作为listview的条目
        /*
         * position：本次getView方法调用所返回的view对象在listView中处于第几个条目，position的值就为多少
         * */
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            TextView tv = new TextView(MainActivity.this);
            tv.setTextSize(18);
            //获取集合中的元素
            Girl girl = girList.get(position);
            tv.setText(girl.toString());

            return tv;
        }

    }

}

MyOpenSqlHelp.java

数据库帮助器，要用sqlite数据库必须创建的类

package com.example.listviewdemo;

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

public class MyOpenSqlHelp extends SQLiteOpenHelper{

    public static final String CREATE_GIRL = "create table Girl(_id integer primary key autoincrement,Name char(20),Age integer,Phone char(20))" ;
    private Context mContext;
    public MyOpenSqlHelp(Context context, String name, CursorFactory factory,
            int version) {
        super(context, name, factory, version);
        // TODO Auto-generated constructor stub
        mContext = context ;
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        // TODO Auto-generated method stub
        db.execSQL(CREATE_GIRL);
        /*Toast.makeText(mContext,"Create Successded",0).show();*/
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // TODO Auto-generated method stub

    }

}