Validations Example in Kotlin

Validation is a crucial aspect to ensure that user inputs are correct and meet the required criteria. Below is an example of how you can perform basic validation for a simple form with an EditText field in Kotlin

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<layout>
<LinearLayout 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"
    android:orientation="vertical">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Validations"
         />
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Name"
        android:id="@+id/name"/>

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Mobile"
        android:id="@+id/mobile"/>

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="email"
        android:id="@+id/email"/>
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Password"
        android:id="@+id/password"/>

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/valid"

        android:text="Validate"/>

</LinearLayout>
</layout>

MainActivity.kt

package com.androindian.validtion

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Toast
import androidx.databinding.DataBindingUtil
import com.androindian.validtion.databinding.ActivityMainBinding

class MainActivity : AppCompatActivity() {

    var binding: ActivityMainBinding?=null
    var isAllFieldsChecked=false
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding= DataBindingUtil.setContentView(this,R.layout.activity_main)

        binding?.valid?.setOnClickListener {
            isAllFieldsChecked=CheckAllFileds()

            if(isAllFieldsChecked){
                Toast.makeText(this@MainActivity,"Valid",Toast.LENGTH_LONG).show()
            }

        }
    }

    private fun CheckAllFileds(): Boolean {
        if(binding?.name?.length()==0){
            binding?.name?.setError("Name Could not be empty")
            return false
        }
        if(binding?.mobile?.length()==0){
            binding?.mobile?.setError("Mobile Could not be empty")
            return false
        }else if(binding?.mobile?.length()!! <=10){
            binding?.mobile?.setError("Mobile nUmber must 10 digits")
            return false
        }
        if(binding?.email?.length()==0){
            binding?.email?.setError("Email Could not be empty")
            return false
        }
        if(binding?.password?.length()==0){
            binding?.password?.setError("Password Could not be empty")
            return false
        }

        return true
    }
}