Groups in the message path: Trapping Mouseup

Sannyasin Brahmanathaswami brahma at
Thu Dec 12 12:38:16 EST 2019

User Guide: I tell myself periodically to read the whole thing  (be never do…tinyDictionary has me hooked) … here it is, as you says, clearly stated on page 105

If background behavior is false, the group is in the message path for all controls it owns, but is not in the

message path of any other object.

If the background behavior is true, the group is also in the message path for any cards it is placed on. If

you send a message to a card control, the message passes through the control, then the card, then

any background groups on the card in order of number, then the stack.

Since a group owns any controls that are part of the group, if you send a message to a control within a

group, the group is in the message path for its own controls, regardless of whether it’s background

behavior is true or false. If a group has already received a message because it was originally sent to one

of the controls in the group, the message is not sent through the group again after the card has

handled it.

Tip: If you want a handler in a group's script to affect only the objects in the group, place

the following statement at the beginning of the handler:

if the owner of the target is not me then pass message.

This filters out any objects that are not part of the group.

I'm having fun there, but seriously, the User Guide has been pretty good
in recent years. I'm often surprised at how the answers to many forum
questions are covered well in it, yet when I ask about it most people
don't even notice that it's there, the second-from-the-top item in LC's
Help menu.

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