[AdaptivePageLayout] Only reserve space for columns with a Page in them

[Michael Hall]

When you have a PageColumnsLayout and one PageColumn has fillWidth: true, that column should be able to consume the space of any other column that does not have a Page in it, even if it has set minimumWidth or preferredWith

Use Case:

uReadIt will use up to 3 columns if there is space of it, as [SubredditPage][ArticlePage][CommentsPage]. The second column has fillWidth:true. However, opening the [CommentsPage] is optional, and for non-link Reddits posts it will only use [SubredditPage][CommentsPage].

So there are 2 cases where the 3rd column would not have any Page added to it. In those cases, I would like the second column to use the space otherwise reserved for the 3rd column, because fillWidth:true on the second column. Once a Page is added to the 3rd column, then the 2nd column should give up it's space based on the minimumWidth and preferredWidth of the 3rd column.

[Zsombor Egri (zsombi)]

It would be misleading. The fillWidth means that the column will occupy the remaining space even if the other columns have no content. The columns are prepared and should be like that. Usually the last column is expected to fill the width. This has been discussed with UX, and the APL works according to that.

Beside, this would cause relay outing, which also may have performance issues, may cause models to be re-loaded from the web, etc. Of course this depends on the implementation, but it will definitely cause re-rendering for your [ArticlePage].