Kotlin之匿名内部类

1.常规的方式实现匿名内部类，对象表达式：

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

    override fun mouseEntered(e: MouseEvent) {
        // ...
    }
})

具体例子如下： 

private fun setAnimation() {
        val alphaAnimation = AlphaAnimation(0.1f,1.0f)
        alphaAnimation.duration = 1000
        val scaleAnimation = ScaleAnimation(0.1f,1.0f,0.1f,1.0f,ScaleAnimation.RELATIVE_TO_SELF,0.5f,ScaleAnimation.RELATIVE_TO_SELF,0.5f)
        scaleAnimation.duration =1000
        val animationSet = AnimationSet(true)
        animationSet.addAnimation(alphaAnimation)
        animationSet.addAnimation(scaleAnimation)
        animationSet.duration = 1000
        iv_icon_splash.startAnimation(animationSet)
        animationSet.setAnimationListener(object : Animation.AnimationListener{
            override fun onAnimationRepeat(animation: Animation?) {

            }

            override fun onAnimationStart(animation: Animation?) {

            }

            override fun onAnimationEnd(animation: Animation?) {
                newIntent()
                finish()
            }
        })
    }


recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
            override fun onScrollStateChanged(recyclerView: RecyclerView?, newState: Int) {
                super.onScrollStateChanged(recyclerView, newState)
                var layoutManager: LinearLayoutManager = recyclerView?.layoutManager as LinearLayoutManager
                var lastPositon = layoutManager.findLastVisibleItemPosition()
                if (newState == RecyclerView.SCROLL_STATE_IDLE && lastPositon == mList.size - 1) {
                    start = start.plus(10)
                    mPresenter.requestData(keyWord, start)
                }
            }
        })

2、如果对象实例是一个函数接口（Java中只有一个抽象方法的接口），可以使用lambda表达式（Java8开始支持lambda，关于Lambda可以参考该文档）来实现：

val listener = ActionListener { println("clicked") }