Koltin09.继承

MainActivity.kt

package com.example.a02handler

import android.os.Bundle
import android.os.Handler
import android.os.Message
import android.widget.ImageView
import androidx.appcompat.app.AppCompatActivity
import java.lang.ref.WeakReference
import java.math.BigInteger
import java.util.*

class MainActivity : AppCompatActivity() {

    private lateinit var show: ImageView
    enum class week{
        星期一,星期二,星期三,星期四,星期五,星期六,星期日
    }

    class MyHandler(private val activity: WeakReference<MainActivity>) : Handler(){
        private var  imageIds = intArrayOf(R.drawable.java, R.drawable.javaee, R.drawable.ajax, R.drawable.android,
                R.drawable.swift)
        private var currentImageId = 0
        override fun handleMessage(msg: Message) {
            if (msg.what == 0x1211){
                activity.get()?.show?.setImageResource(
                        imageIds[currentImageId++ % imageIds.size]
                )
            }
        }
    }

    val  myHandler = MyHandler(WeakReference(this))
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

//        var result = add(3, 5)
//        test()//函数
//        test1()//类
        test2()//继承
//        test3(); //抽象方法
        test4();

        show = findViewById(R.id.show);
        Timer().schedule(object : TimerTask(){
            override fun run() {
                myHandler.sendEmptyMessage(0x1211)
            }
        }, 0, 1200)
    }

    fun test4() {
        var intman = IntMan()
        println(week.星期二.ordinal)
    }

    /**
     * 抽象方法
     */
    fun test3() {
        var man = Man("男人")
        man.eat()
        man.pee()
        var man2 = Man("男人2")
        man2.eat()
        man2.pee()
        var man3 = Man("男人3")
        man3.eat()
        man3.pee()
        var woman = Wonman("女人")
        woman.eat()
        woman.pee()
        var woman2 = Wonman("女人2")
        woman2.eat()
        woman2.pee()
        var woman3 = Wonman("女人3")
        woman3.eat()
        woman3.pee()

        var humList = listOf<Human>(man, man2, man3, woman, woman2, woman3)
        for (h in humList) {
            h.pee()
        }
    }

    /**
     * 继承
     */
    fun test2() {
        var son = Son()
        println("son's charator ${son.chactor}")
        son.action()
    }

    /**
     * 对象
     */
    fun test1() {
        var result = fact(BigInteger("100"))
        var react = React(20, 10)
        println("gao===:${react.height}")
        println("kuan===:${react.width}")
        react.closeDoor()
        react.selecteMode(1)
        react.start()
//        println("result=====" + result)
    }

    private fun fact(num:BigInteger):BigInteger{
        return if (num == BigInteger.ONE) {
            BigInteger.ONE
        } else{
            num*fact(num - BigInteger.ONE)
        }
    }

    private fun add(a: Int, y: Int) : Int = a + y

    private fun test() {
        val a: Int = 10000
        println("???" + (a === a)) // true，值相等，对象地址相等

        //经过了装箱，创建了两个不同的对象
        val boxedA: Int? = a
        val anotherBoxedA: Int? = a

        //虽然经过了装箱，但是值是相等的，都是10000
        println(boxedA === anotherBoxedA) //  false，值相等，对象地址不一样
        println(boxedA == anotherBoxedA) // true，值相等
    }


}

Son.kt

package com.example.a02handler

class Son : Father(){
    override fun action() {
        println("son action===")
    }
}

Father.kt

package com.example.a02handler

open class Father {
    var chactor:String = "father==="
    open fun action() {
        println("father action=====")
    }
}

输出：

I/System.out: son's charator father===
    son action===
    1

 

本文地址：https://blog.csdn.net/augfun/article/details/108722907