How Only I Get My Code To Avoid The Apps From Being Unsuccessful? When I Pressed The Login Button, The Apps Will Not Be Successful But Goes The Register Page, While The Forgot Password Button Have...

<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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:c&gt;

    <textview>
        android:id="@+id/textView1"
        android:layout_width="wrap_c/&gt;

    <textview>
        android:id="@+id/textView2"
        android:layout_width="wrap_c/&gt;

    <edittext>
        android:id="@+id/editText1"
        android:layout_width="279dp"
        android:layout_height="wrap_c/&gt;

    <textview>
        android:id="@+id/textView3"
        android:layout_width="wrap_c/&gt;

    <edittext>
        android:id="@+id/editText2"
        android:layout_width="279dp"
        android:layout_height="wrap_c&gt;

        <requestfocus />
    </edittext>

    &lt;Button
        android:id="@+id/button2"
        android:layout_width="wrap_c/&gt;

    <checkbox>
        android:id="@+id/checkBox1"
        android:layout_width="wrap_c/&gt;

    &lt;Button
        android:id="@+id/button3"
        android:layout_width="wrap_c/&gt;

    &lt;Button
        android:id="@+id/button1"
        android:layout_width="wrap_c/&gt;

</checkbox></textview></edittext></textview></textview></linearlayout>

package com.example.personaltracker;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.TextView;


public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        final TextView PET = (TextView) findViewById(R.id.textView1);
        TextView Username = (TextView) findViewById(R.id.textView2);
        TextView Password = (TextView) findViewById(R.id.textView3);
        Button forgotpassword = (Button) findViewById(R.id.button3);
        final EditText username = (EditText) findViewById(R.id.editText1);
        final EditText password = (EditText) findViewById(R.id.editText2);
        Button register = (Button) findViewById(R.id.button1);
        CheckBox stayloggedin = (CheckBox) findViewById(R.id.checkBox1);
        Button login = (Button) findViewById(R.id.button2);
        
        login.setOnClickListener(new OnClickListener(){

			@Override
			public void onClick(View arg0) {
				// TODO Auto-generated method stub
				Intent intent = new Intent(getBaseContext(),main_page.class);
				startActivity(intent);
			}
        	
        });
        
        register.setOnClickListener(new OnClickListener(){

			@Override
			public void onClick(View arg0) {
				// TODO Auto-generated method stub
				Intent intent = new Intent(getBaseContext(),register.class);
				startActivity(intent);
			}
        	
        });
        
        forgotpassword.setOnClickListener(new OnClickListener(){

			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				Intent intent = new Intent(getBaseContext(),forgot_password.class);
				startActivity(intent);
			}
        	
        });
  
        
        
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
    
}