getOffsetHeight returns 0 although onload has been called

Hi group, 

Consider an application which has a DeckLayoutPanel as a shell, and has two DockLayoutPanel as children, which means only one child is shown at any time. I am using MVP with Activities and Places, there are two places and each place corresponds to displaying a child. 

When the app is initialised both children are injected (by gin) and added to the DeckLayoutPanel.

And looks like 

class MyApplication {

 MyApplication(DockLayoutPanel child1, DockLayoutPanel child2) {

 ...

}

 ...

}

Application displays child1, user changes to other place to display child2. Everything is displayed fine however I need to calculate an area using getOffsetHeight and getOffsetWidth, however both calls return 0. If now I change the token of the place in the url to another valid token both calls return actual values.

Any ideas why this is happening?

Thanks,

G

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