Contacto

MyActivity.java

public class MyActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_my);
    }


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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId())
        { 
            case R.id.contacto:
                Intent i = new Intent(this, Contacto.class);
                startActivity(i);
                return true;
        }
    }
}

Contacto.java

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class Contacto extends Activity implements View.OnClickListener{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.contacto);
        final Button btnSendMail = (Button) findViewById(R.id.btnEnviarMail);
        btnSendMail.setOnClickListener(this);

    }

    public void onClick(View v){
        //final EditText etDe = (EditText) getView().findViewById(R.id.et_EmailDe);
        final EditText etAsunto = (EditText) findViewById(R.id.et_EmailAsunto);
        final EditText etMensaje = (EditText) findViewById(R.id.et_EmailMensaje);

        //String to = etDe.getText().toString();
        String subject = etAsunto.getText().toString();
        String message = etMensaje.getText().toString();

        Intent email = new Intent(Intent.ACTION_SEND);
        email.putExtra(Intent.EXTRA_EMAIL  , new String[]{"micorre@gmail.com"});
        email.putExtra(Intent.EXTRA_SUBJECT, subject);
        email.putExtra(Intent.EXTRA_TEXT, message);

        // need this to prompts email client only
        email.setType("message/rfc822");

        startActivity(Intent.createChooser(email, "Seleciona un cliente de correo"));
    }
}

my.xml (carpeta menu)

<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context=".MyActivity" >

    <item
        android:id="@+id/contacto"
        android:title="Contacto"
        android:orderInCategory="101"
        ></item>
</menu>

contacto.xml (carpeta layout)

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/linearLayout1"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:padding="5dp"
    android:layout_margin="10dp"
    >

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/scrollView" >

        <LinearLayout
            android:orientation="vertical"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Asunto"
                android:textAppearance="?android:attr/textAppearanceLarge"
                android:layout_marginTop="12dp"
                android:id="@+id/textView1" />

            <EditText
                android:id="@+id/et_EmailAsunto"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:hint="Asunto" >
            </EditText>

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Mensaje"
                android:textAppearance="?android:attr/textAppearanceLarge"
                android:id="@+id/textView10" />

            <EditText
                android:id="@+id/et_EmailMensaje"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:gravity="top"
                android:hint="Mensaje"
                android:inputType="textMultiLine"
                android:lines="5" />

            <Button
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:text="Enviar"
                android:id="@+id/btnEnviarMail" />
        </LinearLayout>
    </ScrollView>

</LinearLayout>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.elpoeta.contacto" >

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MyActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".Contacto"></activity>
    </application>

</manifest>

agregar

<activity android:name=".Contacto"></activity>