android 使用SimpleCursorAdapter将SQLite数据显示到ListView
android 使用SimpleCursorAdapter将SQLite数据显示到ListView
我们知道，使用ListView的时候需要一个数据源，可以是本地数据，可以是网络数据。本篇博文使用SQLite为ListView提供数据源。
一、首先我们需要创建一个数据库表格。
a、建立一个类 DBHelper 继承 SQLiteOpenHelper .
public class DBHelper extends SQLiteOpenHelper {
public DBHelper(Context context) {
super(context, "test2.db", null, 1);
// TODO Auto-generated constructor stub
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
String sql = "create table class(_id integer primary key autoincrement,name varchar(64),number varchar(64))";
//要使用游标适配器，SQLite表格必须包含一栏“_id”
db.execSQL(sql);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
}
}关于SQLite的使用请访问我的另外一篇博文http://blog.csdn.net/q296264785/article/details/53155739
用单元测试的方法给数据库添加一些数据，方便看到效果。
public void add() {
DBHelper dbHelper = new DBHelper(getContext());
SQLiteDatabase database = dbHelper.getReadableDatabase();
ContentValues values = new ContentValues();
values.put("name", "张利利");
values.put("number", "12345");
database.insert("class", null, values);
values.put("name", "李提莫");
values.put("number", "43455");
database.insert("class", null, values);
values.put("name", "王石说");
values.put("number", "42345");
database.insert("class", null, values);
values.put("name", "赵六壳");
values.put("number", "14215");
database.insert("class", null, values);
values.put("name", "郭撒大");
values.put("number", "45234");
database.insert("class", null, values);
values.put("name", "刘䮻明");
values.put("number", "23445");
database.insert("class", null, values);
} c、在XML文件中编辑一个布局界面，下面是效果图：
XML布局文件：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#cccccc"
android:paddingBottom="10sp" >
<TextView
android:id="@+id/textView1"
android:layout_width="0sp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:paddingTop="10dp"
android:text="编号"
android:textColor="#2828ff"
android:textSize="20sp" />
<TextView
android:id="@+id/textView2"
android:layout_width="0sp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:paddingTop="10dp"
android:text="姓名"
android:textColor="#2828ff"
android:textSize="20sp" />
<TextView
android:id="@+id/textView3"
android:layout_width="0sp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:paddingTop="10dp"
android:text="工号"
android:textColor="#2828ff"
android:textSize="20sp" />
LinearLayout>
<ListView
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
ListView>
LinearLayout> d、在Activity中创建一个SimpleCursorAdapter，并且设置给ListView。
import android.app.Activity;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.Menu;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
public class MainActivity extends Activity {
private DBHelper dbHelper;
private SQLiteDatabase database;
private SimpleCursorAdapter adapter;// 简单的游标适配器
private ListView listView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.listView1);
dbHelper = new DBHelper(this);
database = dbHelper.getReadableDatabase();
Cursor c = database.query("class", null, null, null, null, null, null);
String[] from = { "_id", "name", "number" };
int[] to = { R.id.textView1, R.id.textView2, R.id.textView3 };
adapter = new SimpleCursorAdapter(this, R.layout.activity_main, c,
from, to);//改方法在搞版本已经过时，因为如果读取数据库时间过长是系统会报错，新的方法将数据库读取操作放在另外的线程中。
listView.setAdapter(adapter);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}文件目录：
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源代码：
布局文件：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#cccccc"
android:paddingBottom="10sp" >
<TextView
android:id="@+id/textView1"
android:layout_width="0sp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:paddingTop="10dp"
android:text="编号"
android:textColor="#2828ff"
android:textSize="20sp" />
<TextView
android:id="@+id/textView2"
android:layout_width="0sp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:paddingTop="10dp"
android:text="姓名"
android:textColor="#2828ff"
android:textSize="20sp" />
<TextView
android:id="@+id/textView3"
android:layout_width="0sp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:paddingTop="10dp"
android:text="工号"
android:textColor="#2828ff"
android:textSize="20sp" />
LinearLayout>
<ListView
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
ListView>
LinearLayout>DBHelper 类：
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
public class DBHelper extends SQLiteOpenHelper {
public DBHelper(Context context) {
super(context, "test2.db", null, 1);
// TODO Auto-generated constructor stub
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
String sql = "create table class(_id integer primary key autoincrement,name varchar(64),number varchar(64))";
db.execSQL(sql);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
}
}MainActivity：
import android.app.Activity;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.Menu;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
public class MainActivity extends Activity {
private DBHelper dbHelper;
private SQLiteDatabase database;
private SimpleCursorAdapter adapter;// 简单的游标适配器
private ListView listView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.listView1);
dbHelper = new DBHelper(this);
database = dbHelper.getReadableDatabase();
Cursor c = database.query("class", null, null, null, null, null, null);
String[] from = { "_id", "name", "number" };
int[] to = { R.id.textView1, R.id.textView2, R.id.textView3 };
adapter = new SimpleCursorAdapter(this, R.layout.activity_main, c,
from, to);//该方法在高的版本中已经过时，因为在如果读取数据库时间过长系统会报错，新的版本中将数据库读取操作放在另外的线程中。
listView.setAdapter(adapter);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}测试类test
import android.content.ContentValues;
import android.database.sqlite.SQLiteDatabase;
import android.test.AndroidTestCase;
public class test extends AndroidTestCase {
public void create() {
DBHelper dbHelper = new DBHelper(getContext());
SQLiteDatabase database = dbHelper.getReadableDatabase();
}
public void add() {
DBHelper dbHelper = new DBHelper(getContext());
SQLiteDatabase database = dbHelper.getReadableDatabase();
ContentValues values = new ContentValues();
values.put("name", "张利利");
values.put("number", "12345");
database.insert("class", null, values);
values.put("name", "李提莫");
values.put("number", "43455");
database.insert("class", null, values);
values.put("name", "王石说");
values.put("number", "42345");
database.insert("class", null, values);
values.put("name", "赵六壳");
values.put("number", "14215");
database.insert("class", null, values);
values.put("name", "郭撒大");
values.put("number", "45234");
database.insert("class", null, values);
values.put("name", "刘䮻明");
values.put("number", "23445");
database.insert("class", null, values);
}
}