Kotlin 上的 Android：如何将数据从活动传递到事件侦听器？

Question

(Android newbie learning Kotlin here...) I have an app with 3 components: A UI activity where a user indicates what color car she wants to see; A service that uses the device's camera to observe a road and report every car that passes by; And an event listener latched on the service. The job of the event listener is to determine whether any car reported by the camera is of the requested color and, if so, do something about it.

I'm tripping over something that's probably basic: how does the listener know what color to look for? I can:

1. Have the activity (a class) write to a variable owned by the listener (an object) (hmmm...)
2. Have the activity drop the color in an event bus (does it have to be so complicated?)
3. Have the listener reach over and read a screen variable (hmmm...)
4. Use some global variable in some singleton (hmmm...)

What's the proper way to do this? Many thanks!

Answer 1

I think you can take help of the Shared preferences to store the value(ie color)or you can do as you mentioned in the 4th point.