Input Field Validation

activity_main.xml
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<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/LinearLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"    
    tools:context=".MainActivity" >
 <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/et_normal_text"
            android:hint="Enter Normal Text"
            android:inputType="text"
            android:textStyle="bold"/>

    <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/et_email_address"
            android:textStyle="bold"
            android:inputType="textEmailAddress"
            android:hint="Enter Email Address"/>

    <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/et_phone_number"
            android:hint="Enter Phone Number"
            android:inputType="phone"
            android:textStyle="bold"/>

    <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Submit"
            android:id="@+id/btn_submit" />
</LinearLayout>

Validation.java

-----------------

package com.example.inputfieldvalidation;

import android.widget.EditText;

import java.util.regex.Pattern;

public class Validation {

// Regular Expression

    // you can change the expression based on your need

    private static final String EMAIL_REGEX = "^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";

    private static final String PHONE_REGEX = "\\d{3}-\\d{7}";

 

    // Error Messages

    private static final String REQUIRED_MSG = "required";

    private static final String EMAIL_MSG = "invalid email";

    private static final String PHONE_MSG = "###-#######";

 

    // call this method when you need to check email validation

    public static boolean isEmailAddress(EditText editText, boolean required) {

        return isValid(editText, EMAIL_REGEX, EMAIL_MSG, required);

    }

 

    // call this method when you need to check phone number validation

    public static boolean isPhoneNumber(EditText editText, boolean required) {

        return isValid(editText, PHONE_REGEX, PHONE_MSG, required);

    }

 

    // return true if the input field is valid, based on the parameter passed

   /* public static boolean isValid(EditText editText, String regex, String errMsg, boolean required) {

 

        String text = editText.getText().toString().trim();

        // clearing the error, if it was previously set by some other values

        editText.setError(null);

 

        // text required and editText is blank, so return false

        if ( required && !hasText(editText) ) return false;

 

        // pattern doesn't match so returning false

        if (required && !Pattern.matches(regex, text)) {

            editText.setError(errMsg);

            return false;

        };

 

        return true;

    }*/

    public static boolean isValid(EditText editText, String regex, String errMsg, boolean bRequired) {

    // text required and editText is blank, so return false

    String sText = editText.getText().toString().trim();

    // clearing the error, if it was previously set by some other values

    editText.setError(null);

    if (sText.length() == 0) {

    if (bRequired) {

    editText.setError(REQUIRED_MSG);

    return false;

    }

    } else {

    // filled field

    // pattern doesn’t match so returning false

    if (!Pattern.matches(regex, sText)) {

    editText.setError(errMsg);

    return false;

    }

    }

    return true;

    }

 

    // check the input field has any text or not

    // return true if it contains text otherwise false

    public static boolean hasText(EditText editText) {

 

        String text = editText.getText().toString().trim();

        editText.setError(null);

 

        // length 0 means there is no text

        if (text.length() == 0) {

            editText.setError(REQUIRED_MSG);

            return false;

        }

 

        return true;

    }

}

MainActivity.java

--------------------

package com.example.inputfieldvalidation;

import android.os.Bundle;

import android.app.Activity;

import android.text.Editable;

import android.text.TextWatcher;

import android.view.Menu;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.Toast;

public class MainActivity extends Activity {

private EditText etNormalText;

   private EditText etEmailAddrss;

   private EditText etPhoneNumber;

   private Button btnSubmit;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

registerViews();

}

private void registerViews() {

etNormalText = (EditText) findViewById(R.id.et_normal_text);

       // TextWatcher would let us check validation error on the fly

       etNormalText.addTextChangedListener(new TextWatcher() {

           public void afterTextChanged(Editable s) {

               Validation.hasText(etNormalText);

           }

           public void beforeTextChanged(CharSequence s, int start, int count, int after){}

           public void onTextChanged(CharSequence s, int start, int before, int count){}

       });

 

       etEmailAddrss = (EditText) findViewById(R.id.et_email_address);

       etEmailAddrss.addTextChangedListener(new TextWatcher() {

           // after every change has been made to this editText, we would like to check validity

           public void afterTextChanged(Editable s) {

               Validation.isEmailAddress(etEmailAddrss, true);

           }

           public void beforeTextChanged(CharSequence s, int start, int count, int after){}

           public void onTextChanged(CharSequence s, int start, int before, int count){}

       });

 

       etPhoneNumber = (EditText) findViewById(R.id.et_phone_number);

       etPhoneNumber.addTextChangedListener(new TextWatcher() {

           public void afterTextChanged(Editable s) {

               Validation.isPhoneNumber(etPhoneNumber, false);

           }

           public void beforeTextChanged(CharSequence s, int start, int count, int after){}

           public void onTextChanged(CharSequence s, int start, int before, int count){}

       });

 

       btnSubmit = (Button) findViewById(R.id.btn_submit);

       btnSubmit.setOnClickListener(new View.OnClickListener() {

           @Override

           public void onClick(View view) {

               /*

               Validation class will check the error and display the error on respective fields

               but it won't resist the form submission, so we need to check again before submit

                */

               if ( checkValidation () )

                   submitForm();

               else

                   Toast.makeText(MainActivity.this, "Form contains error", Toast.LENGTH_LONG).show();

           }

       });

   }

 

   private void submitForm() {

       // Submit your form here. your form is valid

       Toast.makeText(this, "Submitting form...", Toast.LENGTH_LONG).show();

   }

 

   private boolean checkValidation() {

       boolean ret = true;

 

       if (!Validation.hasText(etNormalText)) ret = false;

       if (!Validation.isEmailAddress(etEmailAddrss, true)) ret = false;

       if (!Validation.isPhoneNumber(etPhoneNumber, false)) ret = false;

 

       return ret;

   }

}

Screens

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