实例讲解Android App使用自带的SQLite数据库的基本方法

<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"
  tools:context=".Main" >
 
  <LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal" >
 
    <TextView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:gravity="center"
      android:text="key" />
 
    <EditText
      android:id="@+id/keys"
      android:layout_width="100sp"
      android:layout_height="wrap_content" />
 
    <TextView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:gravity="center"
      android:text="value" />
 
    <EditText
      android:id="@+id/values"
      android:layout_width="100sp"
      android:layout_height="wrap_content" />
 
    <Button
      android:id="@+id/btn"
      android:layout_width="100sp"
      android:layout_height="wrap_content"
      android:text="submit" />
  </LinearLayout>
 
  <LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >
 
    <ListView
      android:id="@+id/lv"
      android:layout_width="match_parent"
      android:layout_height="wrap_content" />
  </LinearLayout>
 
</LinearLayout>

<?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="wrap_content"
  android:orientation="horizontal" >
 
  <TextView
    android:id="@+id/listkey"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="left" />
 
  <TextView
    android:id="@+id/listvalue"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginLeft="300sp" />
 
</LinearLayout>

package com.app.main;
 
import android.annotation.SuppressLint;
import android.app.Activity;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CursorAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
 
public class Main extends Activity {
 
  EditText ed1 = null;
  EditText ed2 = null;
  Button btn = null;
  ListView lv = null;
  SQLiteDatabase db = null;
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
 
    ed1 = (EditText) this.findViewById(R.id.keys);
    ed2 = (EditText) this.findViewById(R.id.values);
    btn = (Button) this.findViewById(R.id.btn);
    lv = (ListView) this.findViewById(R.id.lv);
 
    db = SQLiteDatabase.openOrCreateDatabase(this.getFilesDir().toString()
        + "/my.db3", null);
 
    btn.setOnClickListener(new OnClickListener() {
 
      @Override
      public void onClick(View view) {
 
        String key = ed1.getText().toString();
 
        String value = ed2.getText().toString();
 
        try {
          insertData(db, key, value);
 
          Cursor cursor = db.rawQuery("select * from tb_info", null);
 
          inflateListView(cursor);
 
        } catch (Exception e) {
 
          String sql = "create table tb_info(_id integer primary key autoincrement,db_key varchar(20),db_value varchar(50))";
 
          db.execSQL(sql);
 
          insertData(db, key, value);
 
          Cursor cursor = db.rawQuery("select * from tb_info", null);
 
          inflateListView(cursor);
        }
 
      }
 
    });
 
  }
 
  // 向数据库中插入数据
  private void insertData(SQLiteDatabase db, String key, String value) {
    db.execSQL("insert into tb_info values (null,?,?)", new String[] { key,
        value });
    System.out.println("------------------");
  }
 
  // 向ListView中填充数据
  @SuppressLint("NewApi")
  public void inflateListView(Cursor cursor) {
 
    SimpleCursorAdapter adapter = new SimpleCursorAdapter(Main.this,
        R.layout.mytextview, cursor, new String[] { "db_key",
            "db_value" },
        new int[] { R.id.listkey, R.id.listvalue },
        CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
 
    lv.setAdapter(adapter);
 
  }
 
  @Override
  protected void onDestroy() {
 
    super.onDestroy();
    if (db != null && db.isOpen()) {
      db.close();
    }
  }
 
}

package com.app.db;
 
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
 
public class MySQLiteOpenHelper extends SQLiteOpenHelper {
 
  String createSQL = "create table tb_test(_id integer primary key autoincrement ,name,age )";
 
  public MySQLiteOpenHelper(Context context, String name,
      CursorFactory factory, int version) {
 
    super(context, name, factory, version);
  }
 
  @Override
  public void onCreate(SQLiteDatabase db) {
 
    db.execSQL(createSQL);
 
  }
 
  @Override
  public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
 
  }
 
}

package com.app.main;
 
import android.app.Activity;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.Menu;
import android.widget.Toast;
 
import com.app.db.MySQLiteOpenHelper;
 
public class Main extends Activity {
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
 
    MySQLiteOpenHelper helper = new MySQLiteOpenHelper(this, "my.db3",
        null, 1);
 
    String insertSQL = "insert into tb_test values(null,'wx',18)";
 
    SQLiteDatabase db = helper.getReadableDatabase();
 
    db.execSQL(insertSQL);
 
    Cursor cursor = db.rawQuery("select * from tb_test", null);
 
    cursor.moveToFirst();
 
    int id = cursor.getInt(0);
 
    Toast.makeText(this, id+"",Toast.LENGTH_SHORT).show();
  }
 
  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
 
    getMenuInflater().inflate(R.menu.main, menu);
     
    return true;
  }
 
}