Bad day three, BUT…
Bad day three and the uncooperative xml have started better than expected, though I've yet to figure out why, although I will have to do so later.
The last attempt at cajoling the third app to read its map data comprised of hashing the code around so it would use the xml file that the two working apps used – after about a dozen variation of file and field names, I gave this one up too. It should (I thought) have produced some response, a number of the data names were common as they used the same base code, but there was no response. The loop still ejected itself when it reached the parse line.
Starting fresh this morning, I decided to revise all the xml file names. Formerly, they'd used the default names that came with the source – I reckoned they worked (even if they bore no relation to the content I'd inserted) so who was I to upset things?
A few minutes fiddling, and all the xml files had new names, so all I had to do was change the code in each app to point to the newly named files.
First up were the two functional apps, I had to be sure they were still happy, they were. Unfortunately I still had a breakpoint in one of them (with no escape), so it wanted to read in around 700 data points – with me pressing return to accept each one (no, I didn't, the browser got a ctrl-alt-del shutdown).
Next was the third app (set to read only 5 data point with confirmation). Edited the file to use one of the renamed data sets (whose contents had not been altered) and was more than a little surprised to see the 5 data points be loaded, one at a time as I hit Return, and plotted onto both maps. Even better was the fact that the second (detail) map responded to clicking on points on the first (coarse) map, meaning that the original code was (currently) working happily with google's V2 map API, so the forthcoming code tweaks to upgrade it from V1 to V2 should be straightforward.
At this stage, I have no idea why just changing the xml file names made this start to work, and I'm not going to look until I've gone for a long walk, as staring at the same problem for over 2 days isn't good for you, especially when the solution is obscure, and this one will be obscure when I track it down.
The good news is that with a working and non-working versions of the offending files, I now at least of somewhere to look, even if it it has to be character by character, line by line. I will have my revenge.