Android CoroutineScope Dispatchers.Main主线程delay，kotlin

 

 

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import android.view.View
import android.view.View.OnClickListener
import android.widget.Button
import android.widget.Toast
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.delay
import kotlinx.coroutines.launch

class MainActivity : AppCompatActivity() {
    companion object {
        var TAG = "fly"
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        //点击按钮正常弹出Toast
        findViewById<Button>(R.id.button).setOnClickListener(object : OnClickListener {
            override fun onClick(v: View?) {
                Toast.makeText(
                    applicationContext,
                    TAG + " @${Thread.currentThread().id}",
                    Toast.LENGTH_SHORT
                ).show()
            }
        })

        Log.d(TAG, "1 @${Thread.currentThread().id}")
        CoroutineScope(Dispatchers.Main).launch {
            delay(20_000)
            var id = Thread.currentThread().id
            Log.d(TAG, "launch @$id")
        }
        Log.d(TAG, "2 @${Thread.currentThread().id}")
    }
}

 

 

 

kotlin协程coroutineScope_zhangphil的博客-CSDN博客coroutineScope 创建独立协程作用域，直到所有启动的协程都完成后才结束自己。runBlocking 和 coroutineScope 很像，它们都需要等待内部所有相同作用域的协程结束后才会结束自己。两者主要区别是： runBlocking 阻塞当前线程，而 coroutineScope不会，coroutineScope会挂起并释放底层线程供其它协程使用。kotlin协程coroutineScope。https://blog.csdn.net/zhangphil/article/details/129265638