Though I have solve the problem , but the solution is still a mist.
Capx:https://www.dropbox.com/s/yglvrdm0rldebdx/family-2-family-pickUIDwithcontainer.capx?dl=0
I have three families , "tower", "add" and "attackcolor".
The tower family has two sprites which name "small and "large ". The add family has "add1"and "add2".
The "small" and "add1"are in the same container. Another container is made by"large" and "add2" .
Here is the preset result when "tower" family collide with "attackcolor"family I want to create.
Main event sheet:
Wrong pick result without wait 0 after families created ,set value and pin.
Another wrong pick when wait 0 is not in correct place.
Correct wait event sheet :
It seems like that after creating family with container , a wait 0 action is needed, so the following events of family collide with family could correct pick?