In order to understand what's happening, you need to understand that a .shp or polygon or any other kind of overlay is a special layer that sits over the top of the tableau basemap - but this is a feature, not a bug. It especially stands out if you select one of the shapes, where the rest of the shapes that overlay the map that are unselected grey out, and the selected shape 'highlights' to indicate to the screen reader that one of the overlay shapes has been selected.
I'm not 100% sure this is your requirement, but it sounds that you are looking to indicate different regions on the basemap but not have them selectable. This might be used where the geographic boundaries might not be political ones, but for example a companies distribution area which might cross several states but not necessarily the complete state due to overlap with other distribution hubs.
To do this you need to alter the basemap, which can be done by either connecting to a dedicated .wms server or via mapbox I think. I've only tried the former, not the latter.
Thank you both. However, Peter, if you look at my attached
second workbook copy, and turn to sheet 2, you see that the
very same geometry file by itself easily has its transparency
changed: via the color button as usual. We can see the underlying
map *and* the polygon file.
It is only when I go dual axis to overlay the city, as I did in sheet 1
that the transparency no longer works. Your explanation seems to
imply that transparency for a geometry file should never work, because
it is an overlay. Which I do want it to be.
Yes, Deepak! That's what I wanted. In your worksheet I was able to modify the
transparency of the polygons. Made me so happy :-)
I'm trying to figure out how you did this. You worked on 'Sheet 2', but there are
references in the measures and dimension panes to 'Sheet 1'. Is that fact relevant?
I'm just not clear on how you actually accomplish this solution.
This is absolutely enough for my needs. Just out of curiosity: when I select the Lat
for the city dots, and put count(anon_screen_name) onto size, the city dots don't
change size. Similarly, if I put count(anon_screen_name) onto color, there seem to be
no color gradations, even if I change step size to, say 20. Only two colors are used:
light turquoise and dark blue. I can definitely live with that, but if you have time to
explain, I'd love to understand.
Thank you again,
Good it worked for you!!! then you should mark the CORRECT Answer as CORRECT for other's benefit. Isn't it? By the way I used Full Outer Join on your data with Joining on 0=1