Swago/home/src/main/res/layout/activity_home.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.duolingo.open.rtlviewpager.RtlViewPager
        android:id="@+id/viewPager"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:layout_constraintBottom_toTopOf="@+id/rg"
        app:layout_constraintTop_toTopOf="parent" />


    <RadioGroup
        android:id="@+id/rg"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:gravity="center_vertical"
        android:orientation="horizontal"
        app:layout_constraintBottom_toBottomOf="parent">

        <RadioButton
            android:id="@+id/rbHome"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:checked="true"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/selector_home"
            android:paddingTop="15dp" />


        <RadioButton
            android:id="@+id/rbMessage"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/selector_message"
            android:paddingTop="15dp" />

        <RadioButton
            android:id="@+id/rbMine"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/selector_mine"
            android:paddingTop="15dp" />

    </RadioGroup>

    <TextView
        android:id="@+id/tvMessageNum"
        android:layout_width="12dp"
        android:layout_height="12dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        android:layout_marginBottom="28dp"
        android:layout_marginStart="18dp"
        android:textColor="#fff"
        tools:text="1"
        android:textSize="8sp"
        android:gravity="center"
        android:visibility="gone"
        android:background="@drawable/shape_d54941_circle"/>

</androidx.constraintlayout.widget.ConstraintLayout>