Android Android Architecture Components Custom Lifecycle-aware component


Example

Each UI component lifecycle changed as shown at image. lifecycle state diagram You may create component, that will be notified on lifecycle state change:

public class MyLocationListener implements LifecycleObserver {
    private boolean enabled = false;
    private Lifecycle lifecycle;
    public MyLocationListener(Context context, Lifecycle lifecycle, Callback callback) {
       ...
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    void start() {
        if (enabled) {
           // connect
        }
    }

    public void enable() {
        enabled = true;
        if (lifecycle.getState().isAtLeast(STARTED)) {
            // connect if not connected
        }
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    void stop() {
        // disconnect if connected
    }
}