How to use AntPlus.BikeRadar

compute is only called in data fields.  Are you building a watch app or a data field?

Its a watch app

I thought that was the problem but I am unsure what to use instead, do I simply put all that code in onUpdate?

In a widget or a watch app, onUpdate isn't automatically called for you as it is in a watch face or DF. You need to use a timer or something like another callback to do a WatchUi.requestUpdate.

Also note that using radar may prevent you from uploading to the app store

https://developer.garmin.com/connect-iq/app-review-guidelines/

and

https://forums.garmin.com/developer/connect-iq/w/wiki/10/app-approval-exceptions

Timers aren't really that difficult.  There may be a sample in the SDK, but here are the basics.

Create and start the timer  In this case, it fires every second, 

var timer= new Timer.Timer();
timer.start( method(:onTimer), 1000, true ); 

Then to call onUpdate, this is the callback

function onTimer() {WatchUi.requestUpdate();}

Great, thanks for the help

So Ive got my screen to update now however, the data that returns from my radar is just an array of 0's. From what I've seen I am using BikeRadar correctly so I am unsure as to what I am doing wrong

import Toybox.Graphics;
import Toybox.WatchUi;
import Toybox.AntPlus;
import Toybox.Timer;

class RadarTestView extends WatchUi.View {

function initialize() {
View.initialize();
}
var bikeRadar = new AntPlus.BikeRadar(null);
var data = false;
var radarArray = new [8];
var radarSpeed = new [8];
var d = 0;




function onTimer() {
WatchUi.requestUpdate();
}

// Load your resources here
function onLayout(dc as Dc) as Void {

dc.setColor(Graphics.COLOR_WHITE, Graphics.COLOR_TRANSPARENT);
dc.fillRectangle(0, 0, dc.getWidth(), dc.getHeight());
var timer = new Timer.Timer();
timer.start( method(:onTimer), 1000, true );
}

// Called when this View is brought to the foreground. Restore
// the state of this View and prepare it to be shown. This includes
// loading resources into memory.
function onShow() as Void {
}

// Update the view
function onUpdate(dc as Dc) as Void {
dc.clear();
dc.setColor(Graphics.COLOR_WHITE, Graphics.COLOR_TRANSPARENT);
dc.fillRectangle(0, 0, dc.getWidth(), dc.getHeight());
dc.setColor(Graphics.COLOR_BLACK, Graphics.COLOR_TRANSPARENT);
dc.drawText(
dc.getWidth() / 8, // gets the width of the device and divides by 2
dc.getHeight() / 8, // gets the height of the device and divides by 2
Graphics.FONT_SMALL, // sets the font size
d, // the String to display
Graphics.TEXT_JUSTIFY_LEFT // sets the justification for the text
);
d += 1;
var radarInfo = bikeRadar.getRadarInfo();

if(radarInfo){
for(var i = 0; i < 8; i++){
radarArray[i] = radarInfo[i].range;
radarSpeed[i] = radarInfo[i].speed;
}

}


var drawValues = [1,2,3,4,5,6,7,8];
for(var i = 0; i<8; i++){

dc.setColor(Graphics.COLOR_BLACK, Graphics.COLOR_TRANSPARENT);
dc.drawText(
dc.getWidth() / drawValues[i], // gets the width of the device and divides by 2
dc.getHeight() / drawValues[i], // gets the height of the device and divides by 2
Graphics.FONT_SMALL, // sets the font size
radarArray[i], // distance of each object
Graphics.TEXT_JUSTIFY_LEFT // sets the justification for the text
);
}

}

// Called when this View is removed from the screen. Save the
// state of this View here. This includes freeing resources from
// memory.
function onHide() as Void {
}

}

Are you just using the sim?  Do you have an ANT stick that sees the radar?

You may want to try this on a real device.

I am using a Garmin 530 which is connected to a Varia RTL5I5 to test my program. My program does display an array of Radar Objects but the distance/speed data from said objects are 0 for each.