Android Kotlin: EditText hide keyboard after enter

Introduction

This code snippet showcases an approach to hide the soft keyboard on Android after pressing the enter key while typing in an EditText. It's written in Kotlin, a modern programming language for Android development. The code achieves this behavior by implementing a custom key listener for the EditText.

Breakdown

  1. Setting Up the Layout:

    • The activity_main.xml file defines the user interface layout consisting of an EditText and a TextView. The EditText is where the user types the text, and the TextView displays a message after the user presses enter.

  2. Initializing Variables:

    • In MainActivity.kt, the onCreate function retrieves references to the EditText, TextView, and ConstraintLayout using findViewById.

  3. Creating a Key Listener:

    • A custom View.OnKeyListener is defined. This listener gets triggered whenever a key is pressed on the EditText.

  4. Handling Enter Key Press:

    • Inside the key listener, the code checks for two conditions:

      • p2.action == KeyEvent.ACTION_DOWN: This ensures the key is pressed down (not released).
      • p1 == KeyEvent.KEYCODE_ENTER: This verifies if the pressed key is the enter key.

    • If both conditions are met, the following actions are performed:

      • The text entered in the EditText is retrieved and displayed in the TextView along with a message.
      • The hideSoftKeyboard function is called to hide the keyboard programmatically.
      • Optionally, the focus is cleared from the EditText, and the cursor is hidden.
      • Another optional step involves setting focus on the root ConstraintLayout (can be used for custom behavior).

  5. Hiding the Keyboard:

    • An extension function hideSoftKeyboard is defined for the Activity class.
    • This function retrieves the InputMethodManager service and uses it to hide the soft keyboard from the window associated with the currently focused view.

Summary

This code effectively demonstrates how to hide the keyboard on enter press in an EditText using a custom key listener. It provides clear separation of concerns by defining an extension function for hiding the keyboard. Additionally, it includes optional steps for managing focus and cursor visibility in the EditText.


MainActivity.kt 

package com.cfsuman.kotlintutorials

import android.app.Activity
import android.content.Context.INPUT_METHOD_SERVICE
import android.os.Bundle
import android.view.KeyEvent
import android.view.View
import android.view.inputmethod.InputMethodManager
import android.widget.EditText
import android.widget.TextView
import androidx.constraintlayout.widget.ConstraintLayout


class MainActivity : Activity() {
    private lateinit var editText:EditText
    private lateinit var textView:TextView
    private lateinit var constraintLayout:ConstraintLayout

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

        // get the widgets reference from XML layout
        editText = findViewById(R.id.editText)
        textView = findViewById(R.id.textView)
        constraintLayout = findViewById(R.id.constraintLayout)

        // initialize a new key listener instance
        val keyListener = View.OnKeyListener { p0, p1, p2 ->
            if(p2.action == KeyEvent.ACTION_DOWN
                && p1 == KeyEvent.KEYCODE_ENTER){
                // perform action on enter key press
                textView.text = "Enter Key Pressed \n\n${editText.text}"

                // hide soft keyboard programmatically on enter key press
                hideSoftKeyboard()

                // optionally clear focus and hide cursor from edit text
                editText.clearFocus()
                editText.isCursorVisible = false

                // optional, set focus on root constraint layout
                constraintLayout.isFocusable = true

                true
            }else{
                false
            }
        }


        // add key listener for edit text
        editText.setOnKeyListener(keyListener)
    }
}


// extension function to hide soft keyboard programmatically
fun Activity.hideSoftKeyboard(){
    (getSystemService(INPUT_METHOD_SERVICE) as InputMethodManager).apply {
        hideSoftInputFromWindow(currentFocus?.windowToken, 0)
    }
}
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"
    android:id="@+id/constraintLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:tools="http://schemas.android.com/tools"
    android:background="#DCDCDC"
    android:padding="32dp">

    <EditText
        android:id="@+id/editText"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:layout_marginEnd="8dp"
        android:inputType="text"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.12" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="12dp"
        android:fontFamily="sans-serif-condensed-medium"
        android:gravity="center"
        android:padding="8dp"
        android:textColor="#4F42B5"
        android:textSize="25sp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/editText"
        tools:text="TextView" />

</androidx.constraintlayout.widget.ConstraintLayout>
android kotlin - EditText hide keyboard after enter android kotlin - EditText hide keyboard after enter 2
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