I have a dashboard that shows three series of measures for the same set of business transactions: traffic light for the BT success (failed transaction count), traffic light the response time and an area chart of the response time (see attached screenshot). The three dashlets are stacked so that each column represents the same business transaction. Under the area chart the legend is set to be the measure name. The naming convention for these is <system> BT <service> <method>, e.g. BookingEngine BT FlightManager loadFlightsFromThirdParty.
So it is easily identifiable from the wall board in kiosk mode, the titles at the top are a text dashlet with a one word name for the column beneath (as the measure names are so long). It's a bit of a kludge because I have added spaces here and there for it to line up and it will display slightly differently on different screens, or when cockpit is displayed.
And my question: is there a way to add a simple display name as a legend (but not as the measure name because I need to keep the naming convention described above)
I'm not sure if this helps and I've never done this before (since really it's the same as putting a title on the bottom in some ways) but if you modify the x-axis title in the dashlet properties for charts you can put a simple name of what is being charted - this doesn't help if you have multiple measures but I think it is the closes you can get to a custom legend. Also if you haven't you're able to modify what information is contained in the legend as well but there aren't really any "simple" pieces you can use or create.
I do see usefulness though so that would be a good idea to be able to designate some "freindly" names for charted items and other dashlets if there isn't one alread.
Please correct me if I am wrong, that you are asking for the below legend content and you are looking for the custom name of legend instead the fixed content name.
Our APM version is 6.2.8.x and I could not find the way to give a custom name to measure but I can see in your question tag that you have a 6.5, so might be there is way.
If you edit the dashlet properties, you'll see that there are only certain attributes (such as measure name) that can be used as the legend value, it is not free text entry.
There are a couple different areas where you can enter a custom value on a chart. The chart dashlet name and description can be changed, and are displayed above the chart unless otherwise hidden:
The other option would be the 'Axis' tab, which can be seen in the screenshot as well, there you can enter a custom title for the X-axis, which will appear directly under the X-axis of the chart. However, these are not color coded to the lines in the chart, only the legend has that ability.
For free text entry for the legend, I believe an RFE would be needed.
Hope this helps,