Garmin Watch Face Development

Overview:

This post is a summary of the information I found to develop a simple Garmin Connect IQ watch face that displays content in a JSON format.

Source Code

Developer Setup:

You need these installed before installing the Garmin Connect IQ SDK.

1. Java SDK
2. Visual Studio Code

Follow the instructions here: https://developer.garmin.com/connect-iq/connect-iq-basics/getting-started/ to install the Connect IQ SDK, the Visual Studio Code Monkey C extension and generating a developer key.

Once the Monkey C extension is verified you can create a new Watch Face project from the Visual Studio Code command palette.

Watch Face Contents:

Here are the APIs used to get the information displayed on the watchface:

1. Date and Time: The System.getClockTime() only includes the current time, not date information. Since the watch face also includes the current date the information is loaded through the Gregorian calendar to get current date and time.

var clockTime = Gregorian.info(Time.now(), Time.FORMAT_SHORT);

2. Battery Level: The battery level can be read from the current System.Stats object:

var battery = System.getSystemStats().battery;

3. Step Count: Current steps comes from ActivityMonitor.Info which is accessed through the ActivityMonitor:

var stepCount = ActivityMonitor.getInfo().steps;

4. Heart Rate: How heart rate is accessed depends on the device. This logic will first get the heart rate from Activity.Info or reading the most recent value from the ActivityMonitor.HeartRateIterator:

var newHr=Activity.getActivityInfo().currentHeartRate;
if(newHr==null) {
    var hrh=ActivityMonitor.getHeartRateHistory(1,true);
    if(hrh!=null) {
        var hrs=hrh.next();
        if(hrs!=null && hrs.heartRate!=null && hrs.heartRate!=ActivityMonitor.INVALID_HR_SAMPLE) {
            newHr=hrs.heartRate;
        }
    }    	
}

5. Notification Count: The number of unread messages is available in the System.DeviceSettings object:

var messages = System.getDeviceSettings().notificationCount;

Installing on Device:

1. Build the .PRG file for the watch face by selecting Build for Device from the Visual Studio Code command palette.
   • Select the product you’re building for.
   • Select the folder to put the .PRG file in.
2. Connect your watch to the computer.
   • To browse files on the watch you may need to install additional software. For instance on macOS I use the Android File Transfer tool to get access to the file storage on the Garmin watch.
3. Copy the .PRG file from your computer into the watch’s GARMIN/Apps folder