Binding pattr objects between a subpatch and its parent patch
For the basics of binding a pattr object to another object, see also "Binding a pattr object to another object" and "Binding objects to each other, and to a pattr".
For the basics of binding a pattr object to another object, see also "Binding a pattr object to another object" and "Binding objects to each other, and to a pattr".
If you want two user interface objects (UI) always to display the same information, it might seem sensible to connect the outlet of one to the inlet of the other and vice versa. However, that will lead to an infinite loop unless you do something to stop one of them from always sending out the value. The set message is useful in that regard, because it allows you to set the contents (and the display) of a UI object without causing that object to send out a message of its own. The top part of the patch demonstrates this technique.
If you're unfamiliar with the pattr object, see first the "Introduction to the pattr object".
The pattr object and its related objects such as pattrhub, pattrforward, autopattr, and pattrstorage make it possible for you to store data (or any sort of message, really), recall that data when the patch is reopened, store and recall it from other parts of the patch, and make transitions from one set of stored data to another.