nextcloud-android/src/main/res/layout/send_button.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
 Nextcloud Android client application

 @author Tobias Kaminsky
 Copyright (C) 2017 Tobias Kaminsky
 Copyright (C) 2017 Nextcloud GmbH.

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU Affero General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 GNU Affero General Public License for more details.

 You should have received a copy of the GNU Affero General Public License
 along with this program. If not, see <http://www.gnu.org/licenses/>.
-->

<FrameLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/send_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center_horizontal"
        android:drawablePadding="@dimen/standard_half_padding"
        android:padding="@dimen/standard_padding"
        android:textColor="@color/black"/>
</FrameLayout>