This page contain some examples for the collapsible concept of a popup. Please have a look at the page in the components section for more details.

A popup opened with the help of a controller. The popup contain a required inputfield. The attribute `collapsedMode="absent"` is set, so the 'Submit'-button outside the popup could be executed while popup is hidden. Even if the required inputfield is empty.

Server side popup with `<tc:operation/>`. The attribute `collapsedMode="absent"` is set by default. If you press the 'Submit'-button in the popup, the popup remains open, because the server know the current state.

For the client side popup the attribute `collapsedMode="hidden"` must be set. So the hidden popup is already rendered on the site. Otherwise a client side opened popup has no content.

This leads to the problem of violations of hidden content. In this case you cannot press the 'Submit'-button if the required field is empty. Even if the popup is hidden.

The 'Submit'-button in the popup will close the popup, because the server didn't know the current state.

To avoid server request, the attribute `omit="true"` is added to the 'Open'-button and the 'Close'-button.

The opening of the popup is client side. Therefor the popup will be closed after pressing the 'Submit'-button which reload the page.