匿名内部类

结论

kotlin中没有匿名内部类的概念，可以使用对象表达式或者对象声明达到匿名内部类的效果

对象表达式

单接口单函数

btn.setOnClickListener(object : OnClickListener{
    // 处理单击事件逻辑
    *** 
});

单接口多函数

window.addMouseListener(object : MouseAdapter() {
    override fun mouseClicked(e: MouseEvent) {
        // ...
    }
    override fun mouseEntered(e: MouseEvent) {
        // ...
    }
})

实现多个接口

val a = 10
val listener = object : Info("submit"),IClickListener {
    override fun doClick() {
        println("a:$a")
    }
}
listener.doClick() // 打印 a:10

doOnEach的实现

 fun testDoOnEachOperator() {
        Observable.just(5)
                .compose(useSchedulers())
                .doOnRequest {
                    Log.i("grass", "doOnRequest: $it")
                }
                .doOnNext {
                    Log.i("grass", "doOnNext: ")
                }
                .doOnEach(object : Observer<Int> {
                    override fun onNext(t: Int?) {
                        Log.i("grass", "each onNext: " + t)
                    }
                    override fun onError(e: Throwable?) {
                        Log.i("grass", "each onError: " + e.toString())
                    }
                    override fun onCompleted() {
                        Log.i("grass", "each onCompleted: ")
                    }
                }).subscribe({
            value ->
            Log.i("grass", "onNext: " + value)
        }, {
            throwable ->
            Log.i("grass", "onError: " + throwable.toString())
        }, {
            Log.i("grass", "onComplete ")
        })
    }

对象声明

对象声明必须是全局的

class MainActivity : AppCompatActivity() {
    object doOnEachObserver : Observer<Int> {
        override fun onCompleted() {
            TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
        }
        override fun onError(e: Throwable?) {
            TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
        }
        override fun onNext(t: Int?) {
            TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
        }
    }

this@xxxx的用法

匿名对象内部访问外部对象

 ## MainActivity
 findViewById<ImageButton>(R.id.notify_emui_btn).setOnClickListener {
            showNotification(this@MainActivity, R.mipmap.emui_icon)
        }

参考

1. Kotlin-对象表达式，对象声明及伴随对象 - 行云间专栏 - CSDN博客
2. Kotlin之匿名内部类 - easion_zms的专栏 - CSDN博客
3.