The Button Link node (

) adds link to a button in an user input or selectable input.
 
    To add a Button Link node, right-click a 
User Input or 
Selectable Input node and select it from the 
Buttons menu.
 
    The Settings window has the following section:
 
    Use this option to define a link to a locally defined menu under Definitions Library>Auxiliary Definitions, which you select from the 
Link list. Click the 
Add button (

) to display a quick menu where you can select a source to add in to the list and use it as the current reference. A 
Confirm Operation dialog box will appear and ask for confirmation if there is already a reference exist in the 
Link list. Click the 
Go to Source button 

 to move to the referenced node in the 
Link list. Parameters appear that have been defined in the locally defined menu node, and you can edit their expressions in the 
Expressions column under 
Menu item parameters unless they have been defined as read only.
 
    Use this option to define a link to a built-in Java maker. From the Package list, select 
COMSOL Multiphysics or any other available package. Then select a link from the 
Link list (which by default is set to 
Not active). When you have selected an active link, you can also enter an icon file and a title in the 
Icon field and 
Text field, respectively. You can use this option to link from a Physics Builder maker to a Java maker. With a Java maker, you can have more control than with the Physics Builder maker.
 
    Use this option to define a link from an external resource, which you import from a file that you specify from the Imported file list. The 
Imported file list contains all 
Import nodes under 
External Resources. It is used by all link nodes in the Physics Builder, so the user interface is the same for all of them. Then select a menu or menu item from the 
Link list. Parameters appear that have been defined in the externally defined menu node, and you can edit their expressions in the 
Expressions column under 
Menu item parameters unless they have been defined as read only.