handle background notifications

[BryanYin]

Description Hi,

I'm developing an app integrates HuanXin. Now I'm getting stuck dealing with background(App killed) notifications.

According to the docs, Push#registerBackgroundMessageHandler only works for Data Messages, but I have consulted with HuanXin, their system can only send Notification Messages when app is in BG or killed.

Expected behavior I want to understand,

1. HuanXin can only send Notification Messages when app is in BG or killed, is this true?
2. if 1 is true, then how to handle Notification Messages when app is in BG or killed?

I'm new to Flutter, thank you for your help in advance!

Environment

• Platform: see below output from flutter doctor.
• Kit: Push
• Kit Version: 6.5.0+300
• OS Version: HMS
• Your Location/Region: China

Doctor summary (to see all details, run flutter doctor -v): [✓] Flutter (Channel stable, 3.3.1, on macOS 12.5 21G72 darwin-arm, locale en-CN) [✓] Android toolchain - develop for Android devices (Android SDK version 33.0.0) [✓] Xcode - develop for iOS and macOS (Xcode 14.0.1) [✓] Chrome - develop for the web [!] Android Studio (not installed) [✓] IntelliJ IDEA Ultimate Edition (version 2022.2) [✓] VS Code (version 1.71.2) [✓] Connected device (2 available) [✓] HTTP Host Availability