GlobalVariableContext.useSetValue();

example.jsx

import React from "react";
import { Button } from "react-native";

import * as GlobalVariableContext from "./config/GlobalVariableContext";

export const MyVariableSetter = () => {
  const setGlobalVariable = GlobalVariableContext.useSetValue();
  const myNewValue = { key: "mySettableGlobal", value: "new value" };
  
  return (
    <Button onPress={() => setGlobalVariable(myNewValue)}>
      "Update a Variable"
    </Button>
  );
};