private JPanel createAllocationOffsetPanel() {

		JPanel panel = new JPanel(new HorizontalLayout(5));

		decrementButton = new GButton(DECREMENT_ICON);
		decrementButton.setFocusable(false);
		decrementButton.setToolTipText("Decrement allocation unit offset");
		decrementButton.addActionListener(e -> adjustAllocationOffset(-1));
		panel.add(decrementButton);

		incrementButton = new GButton(INCREMENT_ICON);
		incrementButton.setFocusable(false);
		incrementButton.setToolTipText("Increment allocation unit offset");
		incrementButton.addActionListener(e -> adjustAllocationOffset(1));
		panel.add(incrementButton);

		allocationOffsetLabel = new JLabel();
		allocationOffsetLabel.setHorizontalTextPosition(SwingConstants.LEFT);
		panel.add(allocationOffsetLabel);

		return panel;
	}
<code>BitFieldEditorPanel</code> provides the ability to add or modify bitfields
within non-packed structures.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/compositeeditor/BitFieldEditorPanel.java