Android 数据库

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="创建数据库"
        android:id="@+id/btn1"
        ></Button>
 
 
</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity：

package com.example.database;
 
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
 
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
 
public class MainActivity extends AppCompatActivity {
    private  MydatabaseHelper dbHelper;
 
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        dbHelper = new MydatabaseHelper(this,"BookStore.dp",null,1);
        Button createDatabase = (Button) findViewById(R.id.btn1);
        createDatabase.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                dbHelper.getWritableDatabase();
            }
        });
    }
}

MydatabaseHelper：（数据库的管理类）

package com.example.database;
 
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;
 
public class MydatabaseHelper extends SQLiteOpenHelper {
    public static final String CREATE_BOOK = "Create table Book("
            +"id integer primary key autoincrement,"
            +"author text,"
            +"price real,"
            +"pages integer,"
            +"name 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 sqLiteDatabase) {
        sqLiteDatabase.execSQL(CREATE_BOOK);
        Toast.makeText(mContext,"Create succeed",Toast.LENGTH_SHORT).show();
    }
 
    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {
 
    }
}

数据库使用需要安装的插件：