It would be much better to use a Composite Device Handler design, which is a Parent / Child set of Device Handlers. This eliminates any SmartApp in the solution and follows the preferred ST Architecture for Device Handlers.
Take a look at how ST added support for this multi-outlet power strip.
I tried using your Dual Relay Switch to control the GE 28175 Plug-in Dual Dimmer Switch, but when I try to add the virtual devices it is telling me:
“Device Handler: Dimmer Switch Detected
Number of Endpoints: 0 Recommended Type: Dimmer”
Is there a different Device Handler that can be plugged in with your SmartApp to control this device?
You will need to import from code both the main handler and the child channel handler to your ‘My Device Handlers’ section. I’ll be working on it as time permits. Any feedback or assistance would be fantastic.
Okay, I changed the physical device to Z-Wave Ge Dual Dimmer, and I then saw 2 child devices, with (CH1) and (CH2) appended to the end (which were type " Z-Wave Ge Dual Dimmer Outlet"). I did not see those devices show up as controllable devices on the SmartThings GUI, although Alexa did see them when I ran discovery.
If there’s a way to see/control these in the SmartThings GUI as well, please let me know.
So the DH by @Thomas_Slaymaker no longer syncs the child devices to my echo after the required re-linking of ST to Alexa. The parent syncs instead, and the lamps are no longer able to be individually controlled by Alexa or by ST. Is a modification going to be needed to the DH in order for this to work properly again? Looking for developers to have a look and provide opinions if possible. It appears Thomas is no longer active in the community. I sent him a DM, and no reply.
I have included screenshots of the device configuration page in the old and new app. As you can see, the outlets are independently controlled in the old, with 2 different dimming settings. The new doesn’t have this.
I’ve done some VB Development, but never Device handlers/ST development. I’m willing to learn, but it sounds like Groovy is going away and will be replaced by something else for which no details have been provided.