handler 与Thread 的组合在程序中应用很广，在此稍微记录一下：
首先先创建 一个thread 与 handler：
private var thread :Thread? = null
private var handler :Handler =object : Handler(){ //此处的object 要加，否则无法重写 handlerMessage
override fun handleMessage(msg: Message?) {
super.handleMessage(msg)
if(msg?.what == 0){
Toast.makeText(applicationContext,"子线程消息",Toast.LENGTH_LONG).show()
}
}
}
创建子线程：
private fun myTherad(){
thread = Thread(Runnable {
kotlin.run {
var message = Message()
message.what = 0
handler.sendMessage(message)
}
})
}在主线程调用：myTherad()
thread?.start()
