How to create your custom button? Issue with design

Question

I am trying to figure it out why my .xml file doesn't provide properly on the emulator. I would like to create a custom button for google sign in.

<?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"
    tools:context=".MainActivity">

    <LinearLayout
        android:id="@+id/btnGoogleSignIn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:gravity="center"
        android:background="@drawable/round_button"
        android:padding="10dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <ImageView
            android:id="@+id/im_google"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal|center_vertical"
            android:paddingLeft="10dp"
            android:src="@drawable/ic_google" />

        <TextView
            android:id="@+id/tx_google"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal|center_vertical"
            android:layout_weight="1"
            android:paddingLeft="10dp"
            android:paddingTop="15dp"
            android:text="Google Sign In"
            android:textSize="20dp" />

    </LinearLayout>

</androidx.constraintlayout.widget.ConstraintLayout>

This is my result in the code, xml view and in emulator.