I have a small program that I want to complete. I’d like to re-create a small application that I created on the windows platform using Visual Basic.
I know that I shouldn’t feel overwhelmed but I do and struggle to make any progress.
The original program is fairly simple on the surface. It is a program that will generate a Garmin FIT file. The FIT file type format is weight scale data format that is used to upload data to the GarminConnect website. On the surface the user interface appears fairly simple.
A field to enter the weight in either KG or pounds, enter in either will populate the other field with the conversion. A slider that can adjust pounds or Kilo values.
A field to enter the percent of body fat or use a slider to adjust the values.
A Date Picker field to set the date, a button to set the date to todays date.
A button to generate the FIT file.
On launch I’d like the fields to populate with the last values that were last active when the user last generated a FIT file.
I am struggling to just create the user interface. Do I need to make a class file where I store the date, weight and fat percentage. The FIT file uses a date format that is Seconds since the start of 1980 or 23:59:59 Dec 31 1979. I won’t go into the full details of the FIT file format, other than some parts are stored in BigEndian and some parts in LittleEndian. I mentioned the seconds since a date… There is also a requirement to generate a CRC16 for the finished file and add the result as the last two characters of the file.
So behind the scenes I want to build a fairly specific file format with a checksum built in.
For now I want the app to just generate the data, a future possiblity would be an array that stores the data with the ability to locally plot the information and still generate the FIT file format for garminconnect.com, but that is only after I get the program working. So do I plan with a class file in mind now so I can have an array of data points and date vlaues?
When the FIT file is uploaded to a users profile on garminconnect.com, the data is added to the users fitness area in an online plot of weight and body fat and other possible scale values, for now I just want to implement Weight and percent of bodyfat.
If there is anyone that could help me to get started just getting the user interface working, so that I can get access to the data I would appreciate it. I am fairly confident I can get the parts working behind the scenes that do the CRC calculation and build the string in the format of the FIT file. Saving that file out might still be a problem as I have never saved a string out to a file yet on xcode.
Anyone want to help?