Getting started with charting

I started using the http://www.achartengine.org library in my app today. Have not integrated it properly yet. So far I have just shoved the demo activity into my existing app. This is the jar and what goes where part of the job out of the way, so now I just have to get the hang of the renderers and pick a nice looking chart. More on this as I use it, but so far it looks nice. Tons of places to use charts in just about any app.

Fixed a bunch of problems related to how activities are kicked off when you are expecting a result. Using startActivityForResult and calling finish from the target Activity means that your user does not end up meandering through no longer relevant Activities as they press the back button. The overall flow is now much improved.

Still getting tripped up by the upgrade path for a modified database. I reckon this should be a straightforward, almost mechanical method to write (the override of SQLiteOpenHelper.onUpgrade()), but I keep getting knotted up in it. On my workstation it's fine, but on my device, not so much. This is presumably because I only deploy to the device now and again. This means that several chunks of upgrade SQL need to be run in the correct order, rather than the simple chunks getting run every time I make a minor change on my machine. Will have to thrash this one out soon as it is costing me too much time.

Exceptions - I had been getting several situations where I was not getting exceptions even though the emulator had hung (awaiting launch of Activity). It turned out that the emulator/eclipse tool set (DDMS most likely) had paused things as they started to go pear shaped. Just clicking resume a few times gave me a nice explicit exception trace to work with.

Started watching this too. Excellent idea. I had developed a simple serializer/deserializer a while ago which dumped arbitrary data to appengine. Happier using a 'real' toolset to do this from now on. I downloaded and installed the beta of the eclipse tooling for this, but did not give it a spin yet.

Now getting over the initial wobbles related to getting a hang of how everything hangs together - list views for example and just how I get references to widgets and where I keep them. Will hopefully start to see development accellerating over the next few days.

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