Simplest Snackbar

Snackbars provide lightweight feedback about an operation. They show a brief message at the bottom of the screen on mobile and lower left on larger devices. Snackbars appear above all other elements on screen and only one can be displayed at a time.

They automatically disappear after a timeout or after user interaction elsewhere on the screen, particularly after interactions that summon a new surface or activity. Snackbars can be swiped off screen.

It's a simplest example to show Snackbar using Kotlin. The layout xml is same as last post "Simple example of Button and Toast".

MainActivity.kt

package android_er.blogspot.com.myapp01

import android.os.Bundle
import android.view.View
import android.widget.Button
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import com.google.android.material.snackbar.Snackbar

private lateinit var btnA: Button
private lateinit var btnB: Button

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

        btnA = findViewById(R.id.btn_A)
        btnB = findViewById(R.id.btn_B)

        btnA.setOnClickListener(
            { view: View ->
                Toast.makeText(
                    this,
                    "Button A pressed",
                    Toast.LENGTH_LONG,
                ).show()
            },
        )

        btnB.setOnClickListener(
            { view: View ->
                val snackbar = Snackbar
                    .make(btnB,
                        "android-er.blogspot.com",
                        Snackbar.LENGTH_LONG)
                snackbar.show()
            },
        )
    }
}

Simple example of Button and Toast (Android Kotlin)

activity_main.xml

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:layout_margin="10dp">

        <Button
            android:id="@+id/btn_A"
            android:layout_width="wrap_content"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:text="Button A"
            android:layout_margin="5dp"/>
        <Button
            android:id="@+id/btn_B"
            android:layout_width="wrap_content"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:text="Button B"
            android:layout_margin="5dp"/>
    </LinearLayout>

</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity.kt

package android_er.blogspot.com.myapp01

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.widget.Button
import android.widget.Toast

private lateinit var btnA: Button
private lateinit var btnB: Button

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

        btnA = findViewById(R.id.btn_A)
        btnB = findViewById(R.id.btn_B)

        btnA.setOnClickListener(
            { view: View ->
                Toast.makeText(
                    this,
                    "Button A pressed",
                    Toast.LENGTH_LONG,
                ).show()
            },
        )

        btnB.setOnClickListener(
            { view: View ->
                Toast.makeText(
                    this,
                    "Button B pressed",
                    Toast.LENGTH_LONG,
                ).show()
            },
        )
    }
}