material-dialogs/library/src/main/res/layout/material_dialog.xml

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

    <LinearLayout
        android:id="@+id/mainFrame"
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/dialog_frame_margin"
        android:layout_marginBottom="@dimen/title_frame_margin"
        android:layout_marginLeft="@dimen/dialog_frame_margin"
        android:layout_marginRight="@dimen/dialog_frame_margin">

        <TextView
            android:id="@+id/title"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="@dimen/title_frame_margin"
            android:textSize="@dimen/title_textsize"
            tools:text="Title"
            android:lineSpacingMultiplier="1.2" />

        <TextView
            android:id="@+id/content"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="@dimen/content_textsize"
            tools:text="Content" />

    </LinearLayout>

    <LinearLayout
        android:id="@+id/customViewScrollParent"
        android:layout_width="fill_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:visibility="gone">

        <com.afollestad.materialdialogs.views.MeasureCallbackScrollView
            android:id="@+id/customViewScroll"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <LinearLayout
                android:id="@+id/customViewFrame"
                android:orientation="vertical"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:paddingTop="@dimen/dialog_frame_margin"
                android:paddingBottom="@dimen/dialog_frame_margin"
                android:layout_marginLeft="@dimen/dialog_frame_margin"
                android:layout_marginRight="@dimen/dialog_frame_margin">

                <TextView
                    android:id="@+id/titleCustomView"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_marginBottom="@dimen/title_frame_margin"
                    android:textSize="@dimen/title_textsize"
                    tools:text="Title" />

            </LinearLayout>

        </com.afollestad.materialdialogs.views.MeasureCallbackScrollView>

    </LinearLayout>

    <View
        android:id="@+id/customViewDivider"
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:visibility="gone" />

    <RelativeLayout
        android:id="@+id/buttonDefaultFrame"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginRight="@dimen/button_padding_frame_side"
        android:layout_marginBottom="@dimen/button_padding_frame_bottom">

        <TextView
            android:id="@+id/buttonDefaultNeutral"
            style="@style/ActionButton"
            android:layout_alignParentLeft="true"
            android:layout_marginLeft="@dimen/neutral_button_margin" />

        <TextView
            android:id="@+id/buttonDefaultNegative"
            style="@style/ActionButton"
            android:layout_toLeftOf="@+id/buttonDefaultPositive" />

        <TextView
            android:id="@+id/buttonDefaultPositive"
            style="@style/ActionButton"
            android:layout_alignParentRight="true" />

    </RelativeLayout>

    <LinearLayout
        android:id="@+id/buttonStackedFrame"
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="@dimen/button_padding_frame_bottom">

        <TextView
            android:id="@+id/buttonStackedPositive"
            style="@style/ActionButtonStacked" />

        <TextView
            android:id="@+id/buttonStackedNegative"
            style="@style/ActionButtonStacked" />

        <TextView
            android:id="@+id/buttonStackedNeutral"
            style="@style/ActionButtonStacked" />

    </LinearLayout>

</LinearLayout>