How do I hide a table that has no data on ireport?

问题

How do I hide a table (not include in layout) that has no data?

回答1:

If you have the table on its own band, what I typically do is set a print when condition on the band that only shows the data if any object in that band has data. Say your table is something like this:

item1 item2 item3

The print when expression would look something like this:

item1 != null || item2 != null || item3 != null

If you're referring to a subreport built using a collection, then I just check to make sure the collection isn't empty:

!subreportCollection.isEmpty()

Putting the print when condition on the band line hides the data, and causes the report to collapse the unused space.

来源：https://stackoverflow.com/questions/5649350/how-do-i-hide-a-table-that-has-no-data-on-ireport