每日总结2023/3/1日

今天学习安卓连接本地数据库sqllite

教学参考视频Android Studio使用自带SQLite数据库/SQLite数据库/SQLiteOpenHelper帮助类_哔哩哔哩_bilibili

 代码

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.a86191.sqllite.MainActivity">

   <Button
       android:layout_width="100dp"
       android:layout_height="100dp"
       android:id="@+id/creat_database"
       android:text="创建数据库"/>
   <Button

       android:layout_width="100dp"
       android:layout_height="100dp"
       android:text="添加"
       android:id="@+id/add_data"/>

</android.support.constraint.ConstraintLayout>

package com.example.a86191.sqllite;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

private MyDatabaseHelper dbHelper;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

         dbHelper=new MyDatabaseHelper(this,"StudentStore.db",null,1);
        Button createDatabase=(Button)findViewById(R.id.creat_database);
        createDatabase.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                dbHelper.getWritableDatabase();

            }
        });
    }

}

package com.example.a86191.sqllite;

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

/**
 * Created by 86191 on 2023/3/1.
 */

public class MyDatabaseHelper extends SQLiteOpenHelper{
    public static final String CREAT_Student="create table Student("
            +"id interger ,"
            +"name text,"
            +"number text)";
    private Context mContext;
    public MyDatabaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {
        super(context, name, factory, version);
        mContext=context;
    }

    @Override

    public void onCreate(SQLiteDatabase db) {

        db.execSQL(CREAT_Student);

        Toast.makeText(mContext,"Creat succeeded",Toast.LENGTH_SHORT);
    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {

    }
}

本次实现的·是创建学生表，

 通过这里我们把保存的数据库转存到其他文件下，再用sqllite可视化工具打开数据库表查看