NSPanel Update delay and only when page is active

Hi,

I’m struggling with the following

I have some sub screens in my NSpanell but the (sensor) entity values are not filled when I jump to the sub page from the main screen. I have to wait until the value of the entity changes while the sub screen is active.
Is there a way to update the values in the background(while not on the specific subpage, so the values are accurate when I jump to the subpage?

Thanks in advance

Rien