Variable useDataConst

useData<DataProviderName extends DataProviderNames>(
    dataProviderSource: DataProviderName | DataProviders[DataProviderName] | undefined,
  ).DataType(
      selector: DataProviderTypes[DataProviderName][DataType]['selector'],
      defaultValue: DataProviderTypes[DataProviderName][DataType]['getData'],
      subscriberOptions?: DataProviderSubscriberOptions,
    ) => [
      DataProviderTypes[DataProviderName][DataType]['getData'] | PlatformError,
      (
        | ((
            newData: DataProviderTypes[DataProviderName][DataType]['setData'],
          ) => Promise<DataProviderUpdateInstructions<DataProviderTypes[DataProviderName]>>)
        | undefined
      ),
      boolean,
    ]
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React hook to use data from a data provider. Subscribes to run a callback on a data provider's data with specified selector on the specified data type that data provider serves.

Usage: Specify the data provider and the data type on the data provider with useData('<data_provider>').<data_type> and use like any other React hook.

＠example Subscribing to Verse data at JHN 11:35 on the 'quickVerse.quickVerse' data provider:

const [verseText, setVerseText, verseTextIsLoading] = useData('quickVerse.quickVerse').Verse(
  'JHN 11:35',
  'Verse text goes here',
);
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＠param dataProviderSource string name of data provider to get OR dataProvider (result of useDataProvider if you want to consolidate and only get the data provider once)

＠param selector tells the provider what data this listener is listening for

WARNING: MUST BE STABLE - const or wrapped in useState, useMemo, etc. The reference must not be updated every render

＠param defaultValue the initial value to return while first awaiting the data

＠param subscriberOptions various options to adjust how the subscriber emits updates

Note: this parameter is internally assigned to a ref, so changing it will not cause any hooks to re-run with its new value. This means that subscriberOptions will be passed to the data provider's subscribe<data_type> method as soon as possible and will not be updated again until dataProviderSource or selector changes.

＠returns [data, setData, isLoading]

• data: the current value for the data from the data provider with the specified data type and selector. This will be the defaultValue, the resolved data, or a PlatformError if the data provider throws an error. You can call isPlatformError on this value to check if it is an error.
• setData: asynchronous function to request that the data provider update the data at this data type and selector. Returns true if successful. Note that this function does not update the data. The data provider sends out an update to this subscription if it successfully updates data.
• isLoading: whether the data with the data type and selector is awaiting retrieval from the data provider

Throttling. This hook stops a runaway loop that would otherwise lock up the web view. If one subscription receives — or resubscribes — about 100 times within a second, the hook drops its subscription for a few seconds, then re-arms and resubscribes on its own. While throttled it reports data as a PlatformError whose code is RESOURCE_EXHAUSTED, setData as undefined, and isLoading as true, and it logs a warning naming the data type. Handle it as you would any other unresolved state; the usual cause is a selector or dataProviderSource that is rebuilt every render instead of being memoized. (subscriberOptions is held as a ref and cannot cause this.) The error's message is developer-facing English and is not localized — branch on the RESOURCE_EXHAUSTED code and supply your own localized text rather than rendering message to users.