Dynamic ImageButton in Kotlin

Android ImageButton is a user interface widget which is used to display a button having image and to perform exactly like button when we click on it but here, we add an image on Image button instead of text. There are different types of buttons available in android like ImageButton, ToggleButton etc.

We can add an image to the button simply by using attribute android:src in activity_main.xml file or by using setImageResource() method.

In android, we can create ImageButton control in two ways either manually or programmatically.

First we create a new project by following the below steps:

1. Click on File, then New => New Project.
2. After that include the Kotlin support and click on next.
3. Select the minimum SDK as per convenience and click next button.
4. Then select the Empty activity => next => finish.

In this article, we will create the ImageButton programmatically in Kotlin file.

Use LinearLayout in activity_main.xml file

In this file, we will add only the EditText and set attributes for both of them to access into the Kotlin file.

XML

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/linear_layout"
    android:gravity="center">

    <EditText
        android:id="@+id/Num1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:hint= "Enter first number"/>

    <EditText
        android:id="@+id/Num2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:hint= "Enter second number"/>

</LinearLayout>

Modify the strings.xml file to write the name of the application

XML

<resources>
    <string name="app_name">DynamicImageButtonInKotlin</string>
</resources>

Create ImageButton in MainActivity.kt file

We will declare a variable imgBtn to create ImageButton.

 val imgBtn = ImageButton(this)

then, set the image resource for the button using

imgBtn.setImageResource(R.drawable.ic_clear_black_24dp)

In the end, add the button into LinearLayout using

val linearLayout = findViewById(R.id.linear_layout)
  // Adding ImageButton in LinearLayout
  linearLayout.addView(imgBtn)

Other process similar to manually adding the Image Button in the layout.

Kotlin

package com.geeksforgeeks.myfirstkotlinapp

import android.os.Bundle
import android.view.ViewGroup
import androidx.appcompat.app.AppCompatActivity
import android.widget.EditText
import android.widget.ImageButton
import android.widget.LinearLayout
import android.widget.Toast

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        val num1 = findViewById<EditText>(R.id.Num1)
        val num2 = findViewById<EditText>(R.id.Num2)
        val imgBtn = ImageButton(this)
        imgBtn.layoutParams = LinearLayout.LayoutParams(
            ViewGroup.LayoutParams.WRAP_CONTENT,
            ViewGroup.LayoutParams.WRAP_CONTENT)
        imgBtn.setImageResource(R.drawable.ic_clear_black_24dp)


        val linearLayout = findViewById<LinearLayout>(R.id.linear_layout)
        // Adding ImageButton in LinearLayout
        linearLayout.addView(imgBtn)

        imgBtn.setOnClickListener {
         if (num1.text.toString().isEmpty() || num2.text.toString().isEmpty()) {
              Toast.makeText(applicationContext,
                  "Enter both numbers", Toast.LENGTH_SHORT).show()
            }
            else {
                val num1 = Integer.parseInt(num1.text.toString())
                val num2 = Integer.parseInt(num2.text.toString())
                Toast.makeText(applicationContext,
                    "Multiplication of the numbers = " + (num1 * num2),
                    Toast.LENGTH_SHORT).show()
            }
        }
    }
}

AndroidManifest.xml file

XML

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.geeksforgeeks.myfirstkotlinapp">

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

</manifest>

Run as Emulator: