Validations In Android

Validation on user input can be applied by regular expressions. It provides a concise and flexible means for matching strings of text, such as particular characters, words, or patterns of characters.

  

Step:1  Designing xml as follows..

      

main.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

     android:orientation="vertical"

     android:layout_width="fill_parent"

     android:layout_height="fill_parent">

<TextView 

     android:layout_width="fill_parent"

     android:layout_height="wrap_content"

     android:text="@string/hello"/>

<EditText android:id="@+id/editText1"

     android:layout_width="match_parent"

     android:layout_height="wrap_content"

     android:hint="Enter Email Address">

     </EditText>

<EditText android:layout_height="wrap_content"

     android:layout_width="match_parent"

     android:id="@+id/editText2"

     android:inputType="textPassword"

     android:hint="Password">

     </EditText>

<EditText android:layout_height="wrap_content"

     android:inputType="textPassword"

     android:layout_width="match_parent"

     android:id="@+id/editText3"

     android:hint="ConformPassword">
     </EditText>

<Button android:id="@+id/button1"

     android:layout_height="wrap_content"

     android:layout_width="match_parent"

     android:text="CheckValidation"></Button>

</LinearLayout>

Java Code:

package com.murali.validation;

import java.util.regex.Pattern;

import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.EditText;

import android.widget.Toast;

public class EmailValidationActivity extends Activity {

    /** Called when the activity is first created. */

      public EditText txt;

      public EditText pwd_txt;

      public EditText cpwd_txt;

      public Button check;

      public final Pattern EMAIL_ADDS_PATTERN=Pattern.compile("[a-zA-Z0-9+._%-+]{1,256}" +

              "@" + "[a-zA-Z0-9][a-zA-Z0-9-]{0,64}" +

              "(" + "." + "[a-zA-Z0-9][a-zA-Z0-9-]{0,25}" +

              ")+");

    @Override

    public void onCreate(Bundle savedInstanceState) {

     super.onCreate(savedInstanceState);

     setContentView(R.layout.main);

       

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

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

     cpwd_txt=(EditText) findViewById(R.id.editText3);

           

     check=(Button) findViewById(R.id.button1);

     txt.setText("murali@gmail.com");

 

    check.setOnClickListener(new OnClickListener() {

     @Override

     public void onClick(View v) {

       // TODO Auto-generated method stub

                 

     String email=txt.getText().toString();

     String pwd=pwd_txt.getText().toString();

     String cpwd=cpwd_txt.getText().toString(); 

           

    if(CheckEmail(email))

       {

         Toast.makeText(EmailValidationActivity.this,"Valid Email Addresss", 1).show();

         //.....................................       

         if(cpwd.equalsIgnoreCase(pwd))// It is check the condition

                      Toast.makeText(EmailValidationActivity.this,"Password Matched",1).show();

             else

                cpwd_txt.setError("Not Match");

          //.....................................

          }

      else

          {   

            txt.setError("Invalid Email Addresss");

            Toast.makeText(EmailValidationActivity.this,"Invalid Email Addresss", 1).show();

           }

         }

    private boolean CheckEmail(String email) {

    // TODO Auto-generated method stub

      return  EMAIL_ADDS_PATTERN.matcher(email).matches();

              }

         });

     }

}




Output: