How to layout a RelativeLayout in a custom view's onLayout function?

I am implementing a custom view, and I have three subviews that I can't get to appear. It seems like the subviews aren't showing; I have set the backgrounds to be red, blue, and green for now to show where I have made set the layout, which is shown in the picture.

I need the subviews to be shown so that the view is complete.

This is the code I'm using in onLayout for the subviews:

    backButton.layout(leftOffset, topOffset, leftOffset + seventhWidth, topOffset + seventhWidth);
    backButton.setBackgroundColor(Color.RED);
    nextButton.layout((int) (leftOffset + calendarWidth - seventhWidth), topOffset, (int) (leftOffset + calendarWidth), topOffset + seventhWidth);
    nextButton.setBackgroundColor(Color.GREEN);
    monthContainerLayout.layout(leftOffset + thirdWidth, topOffset, (int) Math.round(leftOffset + 2 * thirdWidth), topOffset + seventhWidth);
    monthContainerLayout.setBackgroundColor(Color.BLUE);

This is the layout XML for the red square:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://ift.tt/nIICcg"
    android:id="@+id/back"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:layout_centerVertical="true"
        android:layout_alignParentLeft="true"
        android:src="@drawable/back_icon"
        android:layout_width="wrap_content"
        android:layout_height="@dimen/icon_height" />

</RelativeLayout>

This is what the code and layout currently produces (my custom view is only the calendar):

via Chebli Mohamed