移动端疫情展示

在原来网页版的基础上，又尝试开发出移动端的。首先移动端相较于网页端有很大的不同，在开发中也有过很多的尝试，主要是数据库的操作相较于网页端有很大的差距，APP使用的是自带的数据库管理工具。

 

主要源码：package com.example.justloginregistertest;

import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import java.util.ArrayList;
/public class DBOpenHelper extends SQLiteOpenHelper {
       private SQLiteDatabase db;
    public DBOpenHelper(Context context){
        super(context,"db_test",null,1);
        db = getReadableDatabase();
    }
         @Override
    public void onCreate(SQLiteDatabase db){
        db.execSQL("CREATE TABLE IF NOT EXISTS user(" +
                "_id INTEGER PRIMARY KEY AUTOINCREMENT," +
                "name TEXT," +
                "password TEXT)");
    }
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
        db.execSQL("DROP TABLE IF EXISTS user");
        onCreate(db);
    }
        public void add(String name,String password){
        db.execSQL("INSERT INTO user (name,password) VALUES(?,?)",new Object[]{name,password});
    }
    public void delete(String name,String password){
        db.execSQL("DELETE FROM user WHERE name = AND password ="+name+password);
    }
    public void updata(String password){
        db.execSQL("UPDATE user SET password = ?",new Object[]{password});
    }

        public ArrayList<User> getAllData(){

        ArrayList<User> list = new ArrayList<User>();
        Cursor cursor = db.query("user",null,null,null,null,null,"name DESC");
        while(cursor.moveToNext()){
            String name = cursor.getString(cursor.getColumnIndex("name"));
            String password = cursor.getString(cursor.getColumnIndex("password"));
            list.add(new User(name,password));
        }
        return list;
    }
}