Publish and Subscribe QML Plugin

Publisher

The ValueSpacePublisher element allows us to publish key-value pairs of data to a known path. The path has the form of a directory structure path with the keys acting as files at the end of the path. The process is that the developer declares a ValueSpacePublisher element and then with a given path defines a list of keys. For example

 ValueSpacePublisher {
     id: battery
     path: "/power/battery"
     keys: ["charge", "charging"]
 }

To publish a value the key need only be set to the value. Here we see that the key is expressed as the last name in the path with dot notation followed by the key name.

     battery.charge = 50
     battery.charging = true

 ValueSpaceSubscriber {
     id: batteryCharge
     path: "/power/battery/charge"
 }
 ValueSpaceSubscriber {
     id: batteryCharging
     path: "/power/battery/charging"
 }

 State {
     name: "low"
     when: batteryCharge.value < 25 && !batteryCharging.value
     PropertyChanges {
         target: visualCharge
         color: "red"
     }
 }