Can you pause a state binding?

[OJthe123]

Hi.
I hope you get what i am asking.
Is it possible to bind a component to a state and "pause" it from "listening" to the state?
I want to show values on a line-chart which values update every 500ms.
So the store has a function to add the values and the values itself.
In one component I write values that come from SignalR.
My chart component renders them. But i want to "pause" the graph, while data is written in the background.

[nicholas-greenwood]

yes, save the current values when you pause and pass that array to the chart until you resume

something like this, assuming your store has values: number[]:

const [frozen, setFrozen] = useState<number[] | null>(null)
const values = useValuesStore((state) => frozen ?? state.values)

const pause = () => {
  setFrozen(useValuesStore.getState().values)
}

const resume = () => {
  setFrozen(null)
}

use values for the chart and hook up pause and resume to your buttons

the store keeps collecting data. while paused, the selector returns the same saved array, so those updates won't rerender the chart through this subscription. resume picks up whatever's in the store now

just make sure your updates create a new array and new objects for changed points. if you mutate the old ones, the paused chart's data will change too

react's snapshot comparison, zustand's immutable update guide