Is this a bug, or am I doing something wrong?

I have a layout to view invoices for whichever customer you select so that payments can be applied to their outstanding invoices. I have 2 payment fields, one for normal payments and another for possible write-offs on an invoice. I have a summary field for each of these so that the total amount applied to invoices can be shown, as well as the total amount being written off. I am using a summary field so that the total works with filtered portals.

Here's the problem. If you enter a value into PayField 1, then click out of the field, the summary updates correctly. Same with PayField 2. However, if you enter a value, change an existing one, or delete a value, then click into another field, the summary field immediatly updates to empty. Refreshing the window shows the correct value again, but it also causes screen flickering. Too much of that and the user will not be happy.

I've included a file to help reproduce the problem. Any suggestions would be helpful. Thanks.

DisappearingSummaries.zip

You're right... That is really quirky. I don't think I would have used self join relationships, though. Instead I would have created separate tables for payments, invoices and customers. See the attached file.

Summaries.fp7.zip

that's bizarre; I couldn't figure it out.

The only thing I can add is that when the summary field was being displayed in the Data Viewer, it refreshed automatically as you want it to.

Related summary fields work reasonably well, but they are still not perfect. Try using a calculation field = Sum ( related::field ) instead.

Instead I would have created separate tables for payments, invoices and customers.

Agreed, mfero. This is just a quick file I threw together to get the point across. My actual file is set up in a more realistic manner

Try using a calculation field = Sum ( related::field ) instead.

I've used this many times, and it does work well. The only reason I opted for the summary field is that it works with filtered portals, while the sum field calculates at the data level, and thus doesn't take into account any presentation-level based filtering I've done.

I'll keep working with this. Perhaps the occasional screen refresh is required here. If things get too bad, then there is always another solution. Thanks!