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: