Main.axml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="20dp">
    <TextView
        android:text="Hitung Diskon"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/textView1"
        android:textStyle="bold"
        android:layout_marginBottom="15.5dp" />
    <TextView
        android:text="Jumlah Pembelian Barang"
        android:textAppearance="?android:attr/textAppearanceSmall"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/textView2"
        android:layout_marginTop="6.5dp" />
    <TextView
        android:text="Harga Barang Rp. 300.000,-"
        android:textAppearance="?android:attr/textAppearanceSmall"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/textView2"
        android:layout_marginTop="6.5dp" />
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/inputDiskon"
        android:hint="input jumlah"
        android:layout_marginTop="7.0dp" />
    <Button
        android:text="Hitung"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/btnHitung"
        android:layout_marginTop="5.5dp" />
    <TextView
        android:text="Jumlah Pembelian"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/textView3"
        android:layout_marginTop="10.0dp" />
    <TextView
        android:text="50"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/txtJumlahBeli" />
    <TextView
        android:text="Harga Sebelum Diskon"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/textView5"
        android:layout_marginTop="5.0dp" />
    <TextView
        android:text="1500000"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/txtHargaSebelumDiskon" />
    <TextView
        android:text="Harga Setelah Diskon"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/textView7"
        android:layout_marginTop="7.5dp" />
    <TextView
        android:text="1000000"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/txtHargaSetelahDiskon" />
</LinearLayout>