text: <?xml version="1.0" encoding="utf-8"?>
  <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
          xmlns:app="http://schemas.android.com/apk/res-auto"
          android:layout_width="match_parent"
          android:layout_height="match_parent">
  
      <LinearLayout
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:orientation="vertical">
  
          <com.tyorikan.voicerecordingvisualizer.VisualizerView
                  android:id="@+id/visualizer"
                  android:layout_width="100dp"
                  android:layout_height="100dp"
                  android:layout_gravity="center"
                  android:layout_marginTop="@dimen/spacing_large"
                  android:background="@android:color/black"
                  app:numColumns="4"
                  app:renderColor="@color/renderColor"
                  app:renderRange="top"
                  app:renderType="bar|fade" />
  
          <com.tyorikan.voicerecordingvisualizer.VisualizerView
                  android:id="@+id/visualizer2"
                  android:layout_width="50dp"
                  android:layout_height="150dp"
                  android:layout_gravity="center_horizontal|top"
                  android:layout_marginTop="@dimen/spacing_large"
                  android:background="@android:color/background_light"
                  app:numColumns="10"
                  app:renderColor="@color/renderColor2"
                  app:renderRange="bottom"
                  app:renderType="pixel|fade" />
  
          <com.tyorikan.voicerecordingvisualizer.VisualizerView
                  android:id="@+id/visualizer3"
                  android:layout_width="match_parent"
                  android:layout_height="100dp"
                  android:layout_gravity="center_horizontal|bottom"
                  android:layout_marginTop="@dimen/spacing_large"
                  android:background="@android:color/darker_gray"
                  app:numColumns="100"
                  app:renderColor="@color/renderColor3"
                  app:renderRange="both"
                  app:renderType="pixel" />
  
      </LinearLayout>
  
      <android.support.design.widget.FloatingActionButton
              android:id="@+id/fab"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:layout_gravity="bottom|right"
              android:layout_margin="@dimen/spacing_large"
              android:src="@drawable/ic_mic"
              app:backgroundTint="@android:color/white"
              app:borderWidth="0dp"
              app:fabSize="normal" />
  </FrameLayout>