How to Validate the Edit Text in Android Studio

Introduction

In this article you will learn how to validate edit text in Android.

Validation

Validation is a process to ensure that the value entered by the user is within the accepted boundaries of the application. For example if a user enters a name then the programmer validates the edit text in such a way that it consists of only letters but no numeric values.

Step 1

Create a new project.

Step 2

Now open the XML file:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
tools:context=".MainActivity">
<LinearLayout

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_alignParentTop="true"

            android:orientation="horizontal" android:id="@+id/linearLayout2">

        <TextView

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                android:textAppearance="?android:attr/textAppearanceLarge"

                android:text="Person_Name"

                android:id="@+id/textView1"

                android:layout_gravity="center_horizontal|top"

                android:layout_alignParentTop="true"

                android:layout_toRightOf="@+id/linearLayout2"/>

 <EditText

                android:layout_width="200dp"

                android:layout_height="wrap_content"

                android:inputType="textPersonName"

                android:text=""

                android:id="@+id/editText1"

                android:layout_gravity="center_horizontal|top"

                android:layout_alignTop="@+id/linearLayout2"

                android:layout_alignParentRight="true"/>

</LinearLayout>

 

    <LinearLayout

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_marginTop="80dp"

        android:orientation="horizontal" android:id="@+id/linearLayout">

 

    <TextView

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:textAppearance="?android:attr/textAppearanceLarge"

            android:text="word"

            android:id="@+id/textView"

            android:layout_gravity="center_horizontal|top"

            android:layout_alignParentTop="true"

            android:layout_toRightOf="@+id/linearLayout2"/>

  

    <EditText

            android:layout_width="200dp"

            android:layout_height="wrap_content"

            android:inputType=""

            android:text=""

            android:id="@+id/editText2"

            android:layout_marginLeft="40dp" android:layout_gravity="center_horizontal|top"

            android:layout_alignTop="@+id/linearLayout2"

            android:layout_alignParentRight="true"/>

 

</LinearLayout>

 

   <Button

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="Register"

            android:id="@+id/button"

            android:layout_below="@+id/linearLayout"

            android:layout_centerHorizontal="true"

            android:layout_marginTop="31dp"/>

    ></RelativeLayout>

Step 3
package com.edittextvalidation;
import android.os.Bundle;
import android.app.Activity;

import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

EditText NameEditText,editTextPhoneNumber,wordEditText;

TextView textViewName,textViewAge,textViewword;

Button RegistrationButton; 

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        RegistrationButton=(Button)findViewById(R.id.button);

        NameEditText=(EditText)findViewById(R.id.editText1);

        wordEditText=(EditText)findViewById(R.id.editText2);

        RegistrationButton.setOnClickListener(new View.OnClickListener() {

        @Override

        public void onClick(View view) {

        final String Name=NameEditText.getText().toString();

        final String word=wordEditText.getText().toString();

        if(Name.length()==0)

        {
          NameEditText.requestFocus();
          NameEditText.setError("FIELD CANNOT BE EMPTY");
        }

        else if(!Name.matches("[a-zA-Z ]+"))
        {
             NameEditText.requestFocus();
             NameEditText.setError("ENTER ONLY ALPHABETICAL CHARACTER");
        }

        else if(word.length()==0)
        {
             wordEditText.requestFocus();
             wordEditText.setError("FIELD CANNOT BE EMPTY");
        }
        else
        {
            Toast.makeText(MainActivity.this,"Validation Successful",Toast.LENGTH_LONG).show();
        }
 }
});
    }
}

Step 4

When we entered no value for the person's name:


 

Step 5

When we entered no value for the word:


 

Step 6

When we entered a numeric value:



Step 7

When we entered a valid value: