In Region Position 02, I have a date picker. Then directly below that, in the body, I have an interactive report (with no actions menu). I made it an interactive report so that the column headers will always appear at the top of the page when the user scrolls down. However, when I click on the calendar icon and the calendar menu drop down appears, it appears behind the headers of my interactive report. I have tried to adjust the Z-INDEX in CSS code but that doesn't work.
One note: On the interactive report, when I fix the headers to the report, the calendar drop-down will appear as desired. But, the headers will disappear as the user scrolls down. So, I have to fix the headers to the page.
It looks like this issue has been resolved in the new version.
https://apex.oracle.com/pls/apex/f?p=145797:21
Did you select the correct div to change the z-index value?
In the new version of apex, the selector of date-pop-up is div#ui-datepicker-div, to change write in this page something like this:
div#ui-datepicker-div {
z-index: 99999 !important;
}