private JPanel create() {

		JPanel mainPanel = new JPanel(new PairLayout(5, 5));
		refFunctionField = new JTextField(20);
		refFunctionField.getAccessibleContext().setAccessibleName("Reference Function");
		mainPanel.add(new GLabel("Destination Function/Address:"));
		mainPanel.add(refFunctionField);

		mainPanel.setBorder(BorderFactory.createEmptyBorder(10, 10, 0, 10));
		mainPanel.getAccessibleContext().setAccessibleName("Think Reference Address");
		return mainPanel;
	}
Define the Main panel for the dialog here.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/ThunkReferenceAddressDialog.java