Popup resize behavior (bug)?

Right now if you set the same MaxWidth on the NavigationBar, you will see it perform correctly. I believe this is in the NavigationBarIntro demo too if you need an example.

We've looked into this and the problem is that the Grid always passes double.PositiveInfinity to our NavigationBar.MeasureOverride. So there isn't a way for us to know that there is a MaxWidth restriction other than if you apply it directly on the NavigationBar as mentioned above. Then oddly enough if you grab a splitter from the grid and drag it a pixel, NavigationBar.MeasureOverride does get a restricted non-infinite value from the Grid's MaxWidth. So this would seem to be a bug in the Grid code to me.

Thanks that mostly works. The only thing that doesn't is that it doesn't restrict the resizing of the popup. If you un-minimize, minmize then show the popup again it is set to MaxWidth but the initial resizing is not restricted.

If you set the MaxWidth on the root child element of the pane too, that will prevent the popup from resizing beyond that.

Thanks. I would expect this to just work if the MaxWidth is set on the main control.

No problem, glad to help.

Well for the original thing you posted about, I would expect Grid to pass us down the column's MaxWidth but it doesn't. That SHOULD have updated the NavigationBar's MaxWidth. But since it doesn't do that, it requires explicit setting.

The popup is a different story though because it is based on the selected pane's content, not the NavigationBar. There may be times where you want the content in the popup to be able to expand to a large size while when not minimized it can't. Or in other scenarios maybe you want some panes' content to be able to be large while the rest can't.

In your case you do want them both to be restricted, thus the need to put the MaxWidth on the pane's root content element.

Please contact me offline and I'll get a bug opened on the WPF team for the Grid.