Android meun

package com.example.appdemo

import android.app.ActionBar
import android.content.Intent
import android.graphics.Color
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.*
import android.widget.*
import android.widget.SeekBar.*

class MainActivity : AppCompatActivity(){
    private val btn1:Button by lazy {findViewById<Button>(R.id.btn1)}
    private val btn2:Button by lazy {findViewById<Button>(R.id.btn2)}
    private val linerLayout:LinearLayout by lazy {findViewById<LinearLayout>(R.id.linerLayout)}
    private val myToast:Toast by lazy {Toast(this)}
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        //menuInflater(R.menu.setting,)
        registerForContextMenu(linerLayout)
        btn1.setOnClickListener{
            startActivity(Intent(this,MainActivity2::class.java))
        }
        btn2.setOnClickListener{
            val popupMenu=PopupMenu(this,btn2)
            popupMenu.menuInflater.inflate(R.menu.context,popupMenu.menu)
            popupMenu.setOnMenuItemClickListener(object:PopupMenu.OnMenuItemClickListener{
                override fun onMenuItemClick(p0: MenuItem?): Boolean {
                    when(p0?.itemId){
                        R.id.copy->myToast.setText("copy")
                        R.id.cut->myToast.setText("cut")
                        R.id.tie->myToast.setText("tie")
                    }
                    myToast.show()
                    return true
                }

            })
            popupMenu.show()
        }
    }


    override fun onCreateOptionsMenu(menu: Menu?): Boolean {
        menuInflater.inflate(R.menu.setting,menu)
        return true
    }

    override fun onOptionsItemSelected(item: MenuItem): Boolean {
        when(item.itemId){
            R.id.save->myToast.setText("save")
            R.id.setting->myToast.setText("setting")
            R.id.share->myToast.setText("share")
            R.id.more->myToast.setText("more")
        }
        myToast.show()
        return super.onOptionsItemSelected(item)
    }

    override fun onCreateContextMenu(
        menu: ContextMenu?,
        v: View?,
        menuInfo: ContextMenu.ContextMenuInfo?
    ) {
        //方法一 代码实现 add(第一个参数组id 第二个item id 第三个item排序id
        menu?.add(1,1,1,"copy")
        menu?.add(1,2,2,"cut")
        menu?.add(1,3,3,"paste")
        val addSubMenu = menu?.addSubMenu(1, 4, 4, "more")
        addSubMenu?.add(2,5,1,"linked")
        addSubMenu?.add(2,6,2,"share")
        //方法二 xml
       // menuInflater.inflate(R.menu.context,menu)
        super.onCreateContextMenu(menu, v, menuInfo)
    }

    override fun onContextItemSelected(item: MenuItem): Boolean {
        when(item.itemId){
            1->myToast.setText("copy")
            2->myToast.setText("cut")
            3->myToast.setText("paste")
        }

//        when(item.itemId){
//            R.id.copy->myToast.setText("copy")
//            R.id.cut->myToast.setText("cut")
//            R.id.tie->myToast.setText("tie")
//        }
        myToast.show()
        return super.onContextItemSelected(item)
    }
}

package com.example.appdemo

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import android.view.ActionMode
import android.view.Menu
import android.view.MenuItem
import android.widget.EditText
import android.widget.TextView
import android.widget.Toast

class MainActivity2 : AppCompatActivity(),ActionMode.Callback {
    private val txt: TextView by lazy { findViewById<TextView>(R.id.txt) }
    private val myToast: Toast by lazy { Toast(this) }
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main2)
        txt.setOnClickListener {
            startActivity(Intent(this,MainActivity::class.java))
        }
        startActionMode(this)
    }

    override fun onActionItemClicked(p0: ActionMode?, p1: MenuItem?): Boolean {
        when(p1?.itemId){
            R.id.copy->myToast.setText("copy")
            R.id.cut->myToast.setText("cut")
            R.id.tie->myToast.setText("tie")
        }
        myToast.show()
        return true
    }

    override fun onCreateActionMode(p0: ActionMode?, p1: Menu?): Boolean {
        menuInflater.inflate(R.menu.context,p1)
        return true
    }

    override fun onPrepareActionMode(p0: ActionMode?, p1: Menu?): Boolean {
        Log.e("Tag","prepare")
        return false;
    }

    override fun onDestroyActionMode(p0: ActionMode?) {
        Log.e("Tag","onDestroyActionMode")
    }
}