Android : Java on Android using Android Studio

I will apologize in advance as I'm a newbie to Java and the mobile environment. I tried to find the answer on Stack Overflow but couldn't find it. The program I have is just crashing the emulator and says:

Unfortunately "program name here" has stopped working.

Below is the Java and XML. It compiles okay.

import android.net.Uri;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import android.view.View;
import android.view.View.OnClickListener;



public class IconCMOLogin extends ActionBarActivity {

EditText phlogin,pword,uname;
Button btnSubmit;
String finalstring;
String chp, unm, psw;
Button btn;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_icon_cmologin);

        phlogin = (EditText)findViewById(R.id.phlogin);
        uname = (EditText)findViewById(R.id.uname);
        pword = (EditText)findViewById(R.id.pword);
        chp = phlogin.getText().toString();
        unm = uname.getText().toString();
        psw = pword.getText().toString();
        btn = (Button)findViewById(R.id.btnsubmit);
    /* add in code to create url* (look like this -
    https://app.iconcmo.com/index.asp?action=login&phone=6666666660&username=Ashton758&password=qn69e2ry&hidDateTime=1427407069/
    new Uri.Builder().scheme("http").authority("app.iconcmo.com").path("/index.asp?action=login&phone=").appendQueryParameter("phlogin")
    */
    btnSubmit.setOnClickListener(new OnClickListener()
     {
        @Override
        public void onClick(View v) {
            finalstring = "https://app.iconcmo.com/index.asp?action=login&phone=chp&username=unm&password=psw";
            Toast.makeText(IconCMOLogin.this, finalstring,
                    Toast.LENGTH_SHORT).show();
        }
     });
/*        addListenerOnButton();


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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
*/
    }

}

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" 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=".IconCMOLogin"
    >

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="textPassword"
        android:ems="10"
        android:id="@+id/pword"
        android:hint="Your Password"
        android:layout_below="@+id/uname"
        android:layout_alignLeft="@+id/uname"
        android:layout_alignStart="@+id/uname"
        android:layout_marginTop="76dp" />

    <Button
        style="?android:attr/buttonStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Submit"
        android:id="@+id/btnsubmit"
        android:layout_alignParentBottom="true"
        android:layout_alignLeft="@+id/pword"
        android:layout_alignStart="@+id/pword" />

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="phone"
        android:ems="10"
        android:id="@+id/phlogin"
        android:text="Phone"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="83dp" />

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="textPersonName"
        android:text="Name"
        android:ems="10"
        android:id="@+id/uname"
        android:layout_below="@+id/phlogin"
        android:layout_alignLeft="@+id/phlogin"
        android:layout_alignStart="@+id/phlogin"
        android:layout_marginTop="46dp" />

</RelativeLayout>