Android Sqlite 使用封装

在Android中使用SQLite时，可以创建一个封装类来简化数据库的操作。以下是一个简单的封装类示例，它提供了基本的增删改查操作：

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
 
public class DatabaseHelper extends SQLiteOpenHelper {
 
    private static final String DATABASE_NAME = "mydatabase.db";
    private static final int DATABASE_VERSION = 1;
    private static final String TABLE_NAME = "mytable";
 
    public DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }
 
    @Override
    public void onCreate(SQLiteDatabase db) {
        String CREATE_TABLE = "CREATE TABLE " + TABLE_NAME + "("
                + "ID INTEGER PRIMARY KEY AUTOINCREMENT,"
                + "NAME TEXT,"
                + "AGE INTEGER" + ")";
        db.execSQL(CREATE_TABLE);
    }
 
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
        onCreate(db);
    }
 
    //插入数据
    public boolean insertData(String name, int age) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put("NAME", name);
        contentValues.put("AGE", age);
        long result = db.insert(TABLE_NAME, null, contentValues);
        return result != -1;
    }
 
    //更新数据
    public boolean updateData(String name, int age, int id) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put("NAME", name);
        contentValues.put("AGE", age);
        int result = db.update(TABLE_NAME, contentValues, "ID = ?", new String[]{Integer.toString(id)});
        return result > 0;
    }
 
    //删除数据
    public boolean deleteData(int id) {
        SQLiteDatabase db = this.getWritableDatabase();
        int result = db.delete(TABLE_NAME, "ID = ?", new String[]{Integer.toString(id)});
        return result > 0;
    }
 
    //查询数据
    public Cursor getAllData() {
        SQLiteDatabase db = this.getWritableDatabase();
        return db.query(TABLE_NAME, null, null, null, null, nul