Android Custom Dialog Popup kotlin

Output:

1/  Create and Modify custom_dialog.xml file.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:padding="16dp">

    <TextView
        android:id="@+id/dialogTitle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Custom Dialog"
        android:textSize="18sp"
        android:textStyle="bold"
        android:layout_gravity="center_horizontal" />

    <EditText
        android:layout_marginVertical="24dp"
        android:id="@+id/dialogInput"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Enter some text" />

    <Button
        android:id="@+id/dialogButton"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="Submit" />
</LinearLayout>

2/  Modify activity_main.xml file.

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/showDialogue"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Show custom dialogue"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

3/  Modify the MainActivity.kt file

package com.microappvalley.androidcustomdialogpopupkotlin

import android.app.Dialog
import android.os.Bundle
import android.view.ViewGroup
import android.widget.Button
import android.widget.EditText
import android.widget.TextView
import androidx.activity.enableEdgeToEdge
import androidx.appcompat.app.AppCompatActivity
import androidx.core.view.ViewCompat
import androidx.core.view.WindowInsetsCompat

class MainActivity : AppCompatActivity() {
    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
        }

        val showDialogBtn: Button = findViewById(R.id.showDialogue)

        showDialogBtn.setOnClickListener {showCustomDialog()}
    }

    private fun showCustomDialog() {
        val dialog = Dialog(this)
        dialog.setContentView(R.layout.custom_dialog)
        dialog.setCancelable(true)

        dialog.window?.setLayout(
            ViewGroup.LayoutParams.MATCH_PARENT,
            ViewGroup.LayoutParams.WRAP_CONTENT
        )
        val dialogTitle: TextView = dialog.findViewById(R.id.dialogTitle)
        val dialogInput: EditText = dialog.findViewById(R.id.dialogInput)
        val dialogButton: Button = dialog.findViewById(R.id.dialogButton)

        dialogButton.setOnClickListener {
            val inputText = dialogInput.text.toString()
            if (inputText.isNotEmpty()) {
                dialogTitle.text = "You entered: $inputText"
            }
            dialog.dismiss()
        }

        dialog.show()
    }
}