Create and Login application as above. Validate login data and display Error to user using setError() method.

Activity_Main.xml:

<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"

    tools:context=".MainActivity" >

    <TextView

        android:id="@+id/textView1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignParentLeft="true"

        android:layout_alignParentTop="true"

        android:layout_marginTop="56dp"

        android:text="@string/Username"

        android:textAppearance="?android:attr/textAppearanceMedium" />

    <EditText

        android:id="@+id/editText1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignBottom="@+id/textView1"

        android:layout_alignParentRight="true"

        android:ems="10"

        android:inputType="text" />

    <TextView

        android:id="@+id/textView2"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignRight="@+id/textView1"

        android:layout_below="@+id/textView1"

        android:layout_marginTop="48dp"

        android:text="@string/Password"

        android:textAppearance="?android:attr/textAppearanceMedium" />

    <EditText

        android:id="@+id/editText2"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignBaseline="@+id/textView2"

        android:layout_alignBottom="@+id/textView2"

        android:layout_alignLeft="@+id/editText1"

        android:ems="10"

        android:inputType="textPassword" >

        <requestFocus />

    </EditText>

    <Button

        android:id="@+id/button1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_below="@+id/editText2"

        android:layout_marginTop="68dp"

        android:layout_toLeftOf="@+id/editText2"

        android:text="@string/Login" />

    <Button

        android:id="@+id/button2"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignBaseline="@+id/button1"

        android:layout_alignBottom="@+id/button1"

        android:layout_alignLeft="@+id/editText2"

        android:layout_marginLeft="42dp"

        android:text="@string/Cancel"/>

</RelativeLayout>

Activity_Second.xml

<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" >

    <TextView

        android:id="@+id/textView1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_centerHorizontal="true"

        android:layout_centerVertical="true"

        android:text="@string/Secondform"

        tools:context=".Second" />

    <Button

        android:id="@+id/button1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_below="@+id/textView1"

        android:layout_centerHorizontal="true"

        android:layout_marginTop="22dp"

        android:text="@string/Logout" />

</RelativeLayout>

MainActivity.java

package com.example.loginform;

import android.os.Bundle;

import android.annotation.SuppressLint;

import android.app.Activity;

import android.content.Intent;

import android.view.*;

import android.view.View.OnClickListener;

import android.widget.*;

public class MainActivity extends Activity implements OnClickListener{

           

            EditText name;

            EditText pass;

            Button login;

            Button cancel;

           

            @Override

        protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

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

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

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

        cancel=(Button )findViewById(R.id.button2);

        login.setOnClickListener(this);

        cancel.setOnClickListener(this);

    }

    @Override

    public boolean onCreateOptionsMenu(Menu menu) {

        getMenuInflater().inflate(R.menu.activity_main, menu);

        return true;

    }

            @SuppressLint("ShowToast") @Override

            public void onClick(View v) {

                        String na=name.getText().toString();

                        String pa=pass.getText().toString();

                        switch(v.getId())

                        {

                        case R.id.button1:

                                    if(na.equals("chaitu"))

                                    {         

                                                if( pa.equals("root"))

                                                {

                                                            Intent i = new Intent(this,Second.class);

                                                            i.putExtra("c1", na);

                                                            startActivity(i);

                                                }

                                                else

                                                {

                                                            pass.setError("Invalid Password !");

                                                }

                                    }

                                    else

                                    {

                                                            name.setError("Invalid UserName !");                                                                       

                                    }

                                    break;

                       

                        case R.id.button2:

                                    name.setText("");

                                    pass.setText("");

                                    break;

                                   

                        default:

                                   

                           break;

                        }

                       

                        }

}

Second.java

package com.example.loginform;

import com.example.loginform.R;

import android.os.Bundle;

import android.app.Activity;

import android.view.*;

import android.view.View.OnClickListener;

import android.widget.*;

import android.content.*;

public class Second extends Activity implements OnClickListener{

           

            Button Logout;

            @Override

            protected void onCreate(Bundle savedInstanceState) {

                        super.onCreate(savedInstanceState);

                        setContentView(R.layout.activity_second);

                        Intent i=getIntent();

                        String str = i.getStringExtra("c1");

                        TextView t1 = (TextView )findViewById(R.id.textView1);

                        t1.setText("Logged In Successfully ! "+str);

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

        Logout.setOnClickListener(this);

            }

            @Override

            public boolean onCreateOptionsMenu(Menu menu) {

                        getMenuInflater().inflate(R.menu.activity_second, menu);

                        return true;

            }

            @Override

            public void onClick(View v1) {

switch(v1.getId())

                        {

                        case R.id.button1:

                                    Intent i = new Intent(this,MainActivity.class);

                                    startActivity(i);

                                    finish();

                                    System.exit(0);

                                    break;

                       

                        default:

                                    break;

                        }

                       

            }

}