Example code for automatically reconnecting

sonalideo

Hi.

Is there any full example code for Android on how to reconnect automatically to the device and resume operation, with full serialization/deserialization?

For example, if the device goes out of range, disconnects and then comes close again it should connect. Or even better in the mwBoard class add a reconnect automatically option.

I tried some basic reconnecting every minute on a device not in range but after a while I then get:

java.lang.NullPointerException

10-15 14:05:23.066 28761-32343/? E/AndroidRuntime:     at com.mbientlab.metawear.MetaWearBleService$DefaultMetaWearBoardAndroidImpl.close(MetaWearBleService.java:659)

10-15 14:05:23.066 28761-32343/? E/AndroidRuntime:     at com.mbientlab.metawear.MetaWearBleService$DefaultMetaWearBoardAndroidImpl.connect(MetaWearBleService.java:673)

Eric

You can use the callback functions provided by the ConnectionStateHandler class to .  Serialization is only needed if the board and app state are out of sync, which should not happen on a simple disconnect.

https://github.com/mbientlab/Metawear-SampleAndroidApp/blob/3.1.0/app/src/main/java/com/mbientlab/metawear/app/NavigationActivity.java#L143

KingTalullah

How would you do this in iOS?  If a device goes out of range, I would like the app to attempt to reconnect to it every 1 minute or so.

stephen

The state property is KVO compliant, so after you connect to the device attach an observer and whenever it changes to disconnected, you can call connectWithHandler again.

Take a look at the sample app code here: https://github.com/mbientlab/Metawear-SampleiOSApp/blob/master/MetaWearApiTest/DeviceDetailViewController.m#L305

That will give you an idea of how to use KVO if you are unfamiliar!

Note, that a call to connect and persist indefinitely, so you don't need to keep calling reconnect every minute.  Whenever it comes back it to range you will get a callback indicating connecting was successful