How to make a GridLayout fit screen size in Android using Kotlin?

This example demonstrates how to make a GridLayout fit screen size in Android using Kotlin.

Step 1 − Create a new project in a new project

Step 2 − Add the following code to res/layout/activity_main.xml.

<?xml version="1.0" encoding="utf-8"?>
<GridLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools"
   android:id="@+id/tableGrid"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_gravity="center"
   android:columnCount="4"
   android:orientation="horizontal"
   tools:context=".MainActivity">
   <Button android:text="1" />
   <Button android:text="2" />
   <Button android:text="3" />
   <Button android:text="4" />
   <Button android:text="5" />
   <Button android:text="6" />
   <Button android:text="7" />
   <Button android:text="8" />
   <Button android:text="9" />
   <Button android:text="10" />
   <Button android:text="11" />
   <Button android:text="12" />
   <Button android:text="13" />
   <Button android:text="14" />
   <Button android:text="15" />
   <Button android:text="16" />
</GridLayout>

Step 3 − Add the following code to src/MainActivity.kt

import android.os.Bundle
import android.view.Gravity
import android.widget.GridLayout
import android.widget.ImageView
import android.widget.TableLayout
import androidx.appcompat.app.AppCompatActivity
class MainActivity : AppCompatActivity() {
   override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      setContentView(R.layout.activity_main)
      title = "KotlinApp"
      val gridLayout = findViewById<GridLayout>(R.id.tableGrid)
      gridLayout.removeAllViews()
      val total = 12
      val column = 5
      val row = total / column
      gridLayout.columnCount = column
      gridLayout.rowCount = row + 1
      var i = 0
      var c = 0
      var r = 0
      while (i < total) {
         if (c == column) {
            c = 0
            r++
         }
         val oImageView = ImageView(this)
         oImageView.setImageResource(R.drawable.ic_launcher_background)
         val param = GridLayout.LayoutParams()
         param.height = TableLayout.LayoutParams.WRAP_CONTENT
         param.width = TableLayout.LayoutParams.WRAP_CONTENT
         param.rightMargin = 5
         param.topMargin = 5
         param.setGravity(Gravity.CENTER)
         param.columnSpec = GridLayout.spec(c)
         param.rowSpec = GridLayout.spec(r)
         oImageView.layoutParams = param
         gridLayout.addView(oImageView)
         i++
         c++
      }
   }
}

Step 4 − Add the following code to androidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
   package="com.example.q11">
   <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>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from android studio, open one of your project's activity files and click the Run  icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen.