Tampilan Form Registrasi Android Studio

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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="com.example.lenovo.myapplication.MainActivity">

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:layout_marginTop="33dp"
        app:srcCompat="@drawable/gambar"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true" />

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Form Registrasi"
        android:textSize="20dp"
        android:textStyle="bold"
        android:textAlignment="center"
        android:textColor="@color/colorPrimary"
        android:id="@+id/textView4"
        android:layout_below="@+id/imageView2"
        android:layout_alignParentEnd="true"
        android:layout_marginTop="18dp" />

    <EditText
        android:layout_width="300dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="19dp"
        android:hint="Username"
        android:textSize="15dp"
        android:textColor="@color/colorPrimary"
        android:textColorHint="@color/colorPrimary"
        android:layout_below="@+id/textView4"
        android:layout_centerHorizontal="true"
        android:id="@+id/username" />

    <EditText
        android:layout_width="300dp"
        android:layout_height="wrap_content"
        android:hint="Password"
        android:textSize="15dp"
        android:textColor="@color/colorPrimary"
        android:textColorHint="@color/colorPrimary"
        android:layout_below="@+id/username"
        android:layout_alignStart="@+id/editText"
        android:layout_marginTop="10dp"
        android:id="@+id/password" />

    <EditText
        android:layout_width="300dp"
        android:layout_height="wrap_content"
        android:hint="Ulangi Password"
        android:textSize="15dp"
        android:layout_marginTop="10dp"
        android:textColor="@color/colorPrimary"
        android:textColorHint="@color/colorPrimary"
        android:id="@+id/password_konf"
        android:layout_below="@+id/password" />

    <Button
        android:layout_width="300dp"
        android:layout_height="wrap_content"
        android:hint="Register"
        android:background="@color/colorPrimary"
        android:textColorHint="#fff"
        android:textStyle="bold"
        android:layout_marginTop="10dp"
        android:id="@+id/button"
        android:layout_below="@+id/password_konf" />

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textAlignment="center"
        android:text="You have account ? Sign In."
        android:layout_below="@+id/button"
        android:layout_alignParentStart="true"
        android:layout_marginTop="20dp" />

</RelativeLayout>