SharePoint List Web Part - major caching issues

Hi All,

I've spent a lot of time building a List based company calendar in our SharePoint Intranet Portal, and the calendar itself is working great, however I'm having no end of headaches with the List Web Part. (not just for this calendar, but all list web parts for that matter)

The calendar has a Start and End field - both are Date and Time fields.

A custom view is created for use with the List Web Part to embed an "upcoming week" view, this is based on a filter which checks both Start and End dates to see whether an event exists within or spans the date range from today to 7 days in the future, so it is a rolling 7 day window. This is based on a number of filter criteria which include [Today] and [Today]+6.

The view also has a sort criteria to sort based on the Start (Date/Time) field.

This all works fine when previewing the view within the list itself - at midnight the results update to include events from the day that is now 7 days in the future which were previously excluded. So the view itself is working fine.

However the same view in a List Web part on another page suffers from a ridiculous amount of browser side (?) caching, to the point that it is basically broken and unusable.

When I open the page the next day in a browser (even if the browser was closed) one of three things happens, somewhat at random:

1. The events 7 days in the future (which just came into filter scope today) just don't appear until a forced page reload is done.
2. The events 7 days in the future do appear but they are sorted incorrectly, appearing at the TOP when the date sort order should show them at the BOTTOM.
3. Sometimes 2 happens but the event is shown with the Start and End Date/Time fields empty - so not only is it at the wrong end of the list it doesn't even show a date at all until the page is refreshed.

Here is a picture showing the sort order being incorrect as in case 2:

When these various problems happen a full CTRL-F5 browser refresh always updates the list to be complete, up to date and sorted correctly, however, if after that you click away from the page and follow a link to return to it OR press a regular F5 refresh it goes back to being incorrect!

It takes many page reloads or a lot of time to pass (hours) before it finally settles down and gives the correct results every time. Then the next day the same caching problems happen again. If you go to a new browser or PC the same problems happen again, suggesting this is browser side caching not something at the servers.

While the actual content of the list items update in real-time if you edit the list content in another page (which is pretty cool) the "result set" of list items (which items should or should not be seen) is heavily cached, and the sorting is unreliable.

Has anyone else found a solution to this ? I have already done things like disabling offline mode for the list, (this only seems to affect caching of the actual data in the list items, not caching of filter results) etc and I cannot find a solution.

The only thing I know which would probably work, as I have had to use this approach on another list is to extend the date range of the filter criteria for the view further into the future, then filter out the extra days using json code in "format view - however AFAIK you can only selectively hide rows like this if you use a custom rowFormatter, which means you have to fully re-implement the standard view including hard coding all the columns you want and it still won't look quite the same.

This is a lot of work and maintenance overhead in the future to work around a caching problem that shouldn't exist in the first place.

Any thoughts appreciated as a lot of time and effort has gone into building an entire calendar system around a SharePoint List, only to find that the list web part just doesn't work properly.