I am trying to show can data in dashboard by using low-can-service.

SW：AGL version Dab4.0.0
HW：Renesas m3ulcb

By adding require-api<low-can-service> in dashboard, it will get data in dashboard. But I got a problem that may be block a lot of data in some time. Problem detail:
1)when dashboard started,subscribe to low-can-service by websocket.,and print log when receive can data.
2)use canplayer to continuously send data to vcan0
3)use "journalctl -f" to check can data.
4)change from dashboard screen to homescreen screen. you can see that, dashboard can't received event from low-can-service.
5)wait 5~10 minute in homescreen, then return to dashboard screen, at this moment dashboard received a lot of events in once time, so dashboard can't receive any new event about 10~30 seconds(canplayer continuously sending data to vcan0).

Based on the above, I thought when dashboard is hided, if low-cam-service still continuously sending data to app, it will cause a lot of data blocked. May be caused other problems. So I thought its maybe an issue about app framework, can app framework fix this issue?
My solution is add a dbus signal in windowmanager when app layer display status has changed,while app receive this signal, it can unsubscribe to low-can-service.
More details was in SPEC-712.