I’m working on a WinCE 6.0 system with a touchscreen that stores its calibration data (x-y location, offset, etc.) in the system registry (HKLM\HARDWARE\TOUCH). Right now, I’m placing the cal values into registry keys that get put into the OS image at build time. That works fine for the monitor that I get the original cal values from, but when I load this image into another system with a different monitor, the touchscreen pointer location is (understandably) off, because the two monitors do not have the same cal values.
My problem is that I don’t know how to properly store values into the registry so that they persist after a power cycle. See, I can recalibrate the screen on the second system, but the new values only exist in volatile memory. I suggested to my boss that we could just tell our customer to leave the power on the unit at all times — that didn’t go over well.
I need advice on how to save the new constants into the registry, so that we can calibrate the monitors once before shipping them out to our customer, and not have to make separate OS images for each unit we build.
A C# method that is known to work in CE6.0 would be helpful. Thanks.
-Odbasta
I think what you’re probably looking for is the Flush function of the RegistryKey class. This is normally not necessary (the registry is lazily-flushed by default), but if the power is turned off on the device before the system has a chance to do this, changes will be discarded:
http://msdn.microsoft.com/en-us/library/microsoft.win32.registrykey.flush.aspx
This function is available in .NET Compact Framework version 2.0 and better.