private void paintFieldBackground(Graphics g, int fieldNum,
			FieldBackgroundColorManager colorManager) {
		Color fieldBackgroundColor = colorManager.getBackgroundColor();
		if (fieldBackgroundColor == null) {
			return;
		}
		g.setColor(fieldBackgroundColor);
		g.fillRect(fields[fieldNum].getStartX(), -getHeightAbove(), fields[fieldNum].getWidth(),
			getHeight());
	}
Returns the row number of this layout with respect to its containing layout.
@return the row number of this layout with respect to its containing layout.
Ghidra/Framework/Docking/src/main/java/docking/widgets/fieldpanel/support/RowLayout.java