open-keychain/OpenPGP-Keychain/res/layout/sign_key_activity.xml

<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:bootstrapbutton="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="16dp" >

    <TextView
        style="@style/SectionHeader"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="4dp"
        android:text="@string/section_signing_key" />

    <fragment
        android:id="@+id/sign_key_select_key_fragment"
        android:name="org.sufficientlysecure.keychain.ui.SelectSecretKeyLayoutFragment"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="4dp"
        android:layout_marginTop="4dp"
        tools:layout="@layout/select_secret_key_layout_fragment" />

    <TextView
        style="@style/SectionHeader"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="4dp"
        android:layout_marginTop="14dp"
        android:text="@string/section_upload_key" />

    <CheckBox
        android:id="@+id/sign_key_upload_checkbox"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="4dp"
        android:layout_marginTop="4dp"
        android:checked="false"
        android:text="@string/label_send_key" />

    <Spinner
        android:id="@+id/sign_key_keyserver"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="4dp"
        android:layout_marginTop="4dp"
        android:enabled="false" />

    <com.beardedhen.androidbootstrap.BootstrapButton
        android:id="@+id/sign_key_sign_button"
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:layout_marginBottom="4dp"
        android:layout_marginTop="14dp"
        android:text="@string/btn_sign"
        bootstrapbutton:bb_icon_left="fa-pencil"
        bootstrapbutton:bb_type="info" />

</LinearLayout>