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Android

Posted by Andreas Robichaux
Andreas Robichaux
2,426 Points

Need help with distanceBetween method and JSONObject if statement to only get results within a certain radius!

I have all the code and stuff here!

Hi I am trying to implement the distanceBetween method from http://developer.android.com/reference/android/location/Location.html#distanceBetween(double, double, double, double, float[]).

I am new to coding so I believe I am making this harder than it should be but I am not sure why. I am attempting to source that JSON Object and grab the information from FIeld1(callsign), Field2(frequency),Field21(latitude),Field24(latitude). Then I want to run the distanceBetween to find out if it is within a radius of say 350 KM. Can anyone help me with some hints or code please? Thanks!

http://stackoverflow.com/questions/32597669/how-do-i-fix-this-distancebetween-method-syntax-for-android

1 Answer

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Hi Andreas,

The distanceBetween method takes two points, each expressed as a lat & long, and places the results in an array that you pass in as a parameter.

You are getting one lat/long pair from a JSON source; that's fine. You then want to "find out if it is within a radius of say 350 KM". I assume "it" is the lat/long you just got from JSON? So this points need to be within 350km of what? Do you have a lat/long pair for that location?

If you do, then you need to create an array to hold results in the form of a double. Then pass in the two lat/long pairs and this array into distanceBetween. Your answer (in metres and bearings) will be stored in the array you created.

I hope that makes sense.

Steve.