Sent to all background groups when a card they are placed on is opened.
# Metadata
Platforms: desktop, server, mobile OS: mac, windows, linux, ios, android Introduced: 1.0 Security:
# Syntax
openBackground pBackgroundID
# Params
- pBackgroundID : The ID number of the background being opened.
# Examples
on openBackground theBackgroundID -- update content of group end openBackground
on openBackground theBackgroundID if the short name of this card is "highscores" then show button "play again" end if end openBackground
# Description
Handle the openBackground message to change a group's objects, or perform other updates, when a card with the group on it is opened.
The openBackground message is sent to background groups, if there is more than one group on the card, the openBackground message is sent to each one.
The openBackground message is sent after the destination card is visible. To make changes that take effect before the card becomes visible on the screen, use the preOpenBackground message instead.
The actual navigation is not triggered by the openBackground message, so trap the message and not allowing it to pass does not prevent the card with the group from opening.
>*Note:* A group is only considered a background group if its > backgroundBehavior property is set to true.
# Tags
# See
- **keyword:** card - **property:** backgroundBehavior - **message:** preOpenBackground, openCard, startup, newBackground, closeBackground, openStack - **command:** group - **glossary:** message, trap - **control structure:** pass