My second Android application

界面组成：

功能代码： 

import android.os.Bundle
import android.view.View
import android.widget.Button
import android.widget.EditText
import android.widget.ImageView
import android.widget.ProgressBar
import android.widget.TextView
import android.widget.Toast
import androidx.activity.enableEdgeToEdge
import androidx.appcompat.app.AlertDialog
import androidx.core.view.ViewCompat
import androidx.core.view.WindowInsetsCompat

class MainActivity : BaseActivity() {
    private lateinit var editText: EditText
    private lateinit var viewText: TextView

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
        setContentView(R.layout.activity_main)
        ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main)) { v, insets ->
            val systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars())
            v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom)
            insets
        }
        //以上为Android Studio自动生成

        viewText = findViewById<TextView>(R.id.secondTV)
        editText = findViewById<EditText>(R.id.editText)
        val button = findViewById<Button>(R.id.button)
        val image = findViewById<ImageView>(R.id.imageView)
        val progressBarH = findViewById<ProgressBar>(R.id.progressBarH)
        val progressBar = findViewById<ProgressBar>(R.id.progressBar)

        button.setOnClickListener() {
            val message = editText.text.toString()
            //设置图片素材
            image.setImageResource(R.drawable.tzuyu)

            if(message == "") {
                Toast.makeText(this, R.string.warning, Toast.LENGTH_SHORT).show()
            } else {
                viewText.text = getString(R.string.greeting, "main", message)
                //设置进度条可见性，默认为不可见
                if (progressBar.visibility != View.VISIBLE) {
                    progressBar.visibility = View.VISIBLE
                }
                //设置警告对话框
                AlertDialog.Builder(this).apply {
                    setTitle("This is a Diaglog")    //标题
                    setMessage("Maybe there's something wrong")    //讯息
                    //设置正确按钮及其动作
                    setPositiveButton("OK") { dialog, which ->
                        progressBar.visibility = View.GONE
                    }
                    //设置正确按钮及其动作
                    setNegativeButton("Cancel") { dialog, which ->
                    }
                    show()
                }
                /*if (progressBar.visibility != View.VISIBLE) {
                    progressBar.visibility = View.VISIBLE
                }
                //设置条状进度条，每点击一次+10进度
                //进度满时关闭进度条，并将进度清理
                progressBarH.progress = progressBarH.progress + 10
                if (progressBarH.progress == progressBarH.max) {
                    progressBarH.visibility = View.GONE
                    progressBarH.progress = 0
                }*/
            }
        }
    }
}

实现效果：

注：点击“OK”关闭进度条 ，点击“Cancel”保持原状