Login.java

//For Login.java
package com.mark.uricacidevaluator;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.content.Intent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class Login extends ActionBarActivity {
	Button login,newuser;
	EditText uname,pword;
	SqliteController handler;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.login);
		login = (Button)findViewById(R.id.login);
		newuser = (Button)findViewById(R.id.register);
		uname = (EditText)findViewById(R.id.text_uname);
		pword = (EditText)findViewById(R.id.text_pword);

newuser.setOnClickListener(new View.OnClickListener() {

	@Override
	public void onClick(View view) {
		// TODO Auto-generated method stub
			Intent myIntent = new Intent(view.getContext(), Register.class);
			startActivityForResult(myIntent, 0);
			finish();
		}
	});

login.setOnClickListener(new View.OnClickListener() {

	@Override
	public void onClick(View view) {
		// TODO Auto-generated method stub
		if (  ( !uname.getText().toString().equals("")) && ( !pword.getText().toString().equals("")) )
		{
			Intent myIntent = new Intent(view.getContext(), Content.class);
			startActivityForResult(myIntent, 0);
			finish();
		}
		else if ( ( !uname.getText().toString().equals("")) )
		{
			 Toast.makeText(getApplicationContext(),
                     "Password field empty", Toast.LENGTH_SHORT).show();
		}
		else if ( ( !pword.getText().toString().equals("")) )
		{
			Toast.makeText(getApplicationContext(),
                    "Email field empty", Toast.LENGTH_SHORT).show();
		}
		else
		{
			Toast.makeText(getApplicationContext(),
                    "Email and Password field are empty", Toast.LENGTH_SHORT).show();
		}

	}
});

	}

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