Freeze while removing container's child

[dawidpstrak]

Hi. This is how my GUI looks like before removing function Screen link >>.
This is removing function where im getting freeze. contentView.removeChildView(contentView.childAt(0))
And freeze looks like Screen link >>.
When i minimize GUI window or set manually height of it - window unfreeze
and i get effect i wanted Screen link >>
Is that bug or I'm doing something wrong?

EDIT: sometimes i got this error
TypeError: Error processing argument at index 0, conversion failure from null to yue.View