Send event to parent rich dialog

There is no direct solution tailored for your situation. Applications that are built from RichDialogs are in principle loosely coupled components that correspond through broadcasts with each other.

I see two solutions that you could use (both are assuming that your parent dialog is the one that creates the inner dialogs on it's own display)

1) You can provide the inner dialogs with a key (random for current session or static) that they send along with the broadcast. Broadcast receivers can then check the key of the event and thus find out, if it is intended for them.

2) You can create a hidden button on the parent. Hand this button to the children dialogs. If they wish to communicate with the parent they may push the button, which will invoke an event process in the parent that is associated with this button. This solution does not permit to hand along any event parameters, it is simply a notification. This second solution is not really best practice, it should be seen as a work around, that you could try out (I never used this myself, I'd use solution #1).