עיצוב מסך, קובץ xml

<LinearLayout 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"
    android:layout_margin="16dp"
    android:orientation="vertical">

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        app:srcCompat="@android:drawable/btn_star_big_on" />

    <TextView
        android:id="@+id/tvBmi"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:text="TextView"
        android:textSize="24sp" />

    <EditText
        android:id="@+id/etWeight"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:ems="10"
        android:hint=" Weight (kg)"
        android:inputType="numberDecimal"
        android:textSize="24sp" />

    <EditText
        android:id="@+id/etHeight"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:ems="10"
        android:hint="Height (m)"
        android:inputType="numberDecimal"
        android:textSize="24sp" />

    <Button
        android:id="@+id/btnCalculate"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:onClick="calaculate"
        android:text="Calculte" />

</LinearLayout>