snapshot limit questions
Stephen Bannasch
>This release includes some fixes to the content as well as application fixes. The applicationchanges should reduce the number of freezes experienced. Additionally this release includes a limit of 5 to the number of snapshots taken of each component.
Is the limit of 5 settable in otml?
Any problems (other than not being able to take more snapshots of that component) if a learner has already saved more than fivesnapshots?
Is there an associated UI change that helps the user understand why they can't add more snapshots for a component that has already had five saved?
Did you also consider setting a maximum total size for the serialized size of a collection of snapshots for the activity and allowing students to delete snapshots?
Sam Fentress
At 12:13 PM -0500 2/16/10, Scott Cytacki wrote:>This release includes some fixes to the content as well as application fixes. The applicationchanges should reduce the number of freezes experienced. Additionally this release includes a limit of 5 to the number of snapshots taken of each component.
Is the limit of 5 settable in otml?
Any problems (other than not being able to take more snapshots of that component) if a learner has already saved more than fivesnapshots?
Is there an associated UI change that helps the user understand why they can't add more snapshots for a component that has already had five saved?
Did you also consider setting a maximum total size for the serialized size of a collection of snapshots for the activity
and allowing students to delete snapshots?
Sam
Stephen Bannasch
>>Any problems (other than not being able to take more snapshots of that component) if a learner has already saved more than fivesnapshots?
>>
>
>Not that we know of. What kinds of problems were you thinking of?
Just wondering if you tested this condition.
Probably not a problem but I can imagine writing code that set a limit and forgetting in the implementation that existing statemight already go beyond that limit.
>>Is there an associated UI change that helps the user understand why they can't add more snapshots for a component that has already had five saved?
>>
>
>Besides the pop-up messages? No.
>>
>>Did you also consider setting a maximum total size for the serialized size of a collection of snapshots for the activity
>>
>
>No. Besides being technically more difficult, I think it would be hard to explain to a student why it was that they could take 7snapshots of one graph and 13 snapshots of another.
I think having a size quota is pretty simple to understand because it's something people bump up against often.
I agree that implementing a size constraint is more complicated (technically and UI).
>Also the size of the lab book can change at various times outside of the student control -- for instance, the sds can strip outimages and replace them with urls. I think it would be hard to explain to the students why it was that they could suddenly take another 9 snapshots of a model when previously it had told them they could take no more.
>
>>and allowing students to delete snapshots?
>>
>
>They have always been able to do this, and the pop-up messages suggest that they do this if they want to be able to take more snapshots.
Finding which graph to delete can be problematic when different graphs have the same name.
For example in the Penny Warming section for UDL 5-6 Friction there are multiple graphs with the name: "Temperature SensorGraph". Pages 6, 7, and 8 appear to refer to the same graph object while page 10 appears be a new graph with the same.
more UI comments:
When I have 10 snaps saved in the lab-book and I have expanded it's size horizontally to see them -- when I select the ninth inthe list the lab-book window resizes, displays the selected snap in the main content area, but the selected icon is scrolled out of sight.
When I have n snaps saved in the lab-book and have any of 1..(n-1) selected after closing and re-opening the lab-book snap n isselected.
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- Stephen Bannasch
Concord Consortium, http://www.concord.org