cordova.getCallbackData

Returns the first Cordova plugin result from the result queue of all asynchronous Cordova plugin front calls, and removes it from the queue.

Syntax

ui.Interface.frontCall("cordova", "getCallbackData",
  [], [result, callback-id])
  1. result - Holds the result returned from the result queue.
  2. callback-id - Holds the callback identifier of the Cordova asynchroneous front call.

Usage

When initiating an asynchronous Cordova plugin front call with callWithoutWaiting, results are stored in the result queue when the Cordova function terminates, and a cordovacallback action is fired if the current dialog defines a corresponding ON ACTION handler.

The getCallbackData front call returns the first Cordova plugin result from the result queue, and removes it from the queue. A subsequent getCallbackData front call gives back the next result and so on.

The first value returned by the front call (result) is the actual result. This can be a variable of type FLOAT, INTEGER, STRING, RECORD or DYNAMIC ARRAY, that matches the JSON equivalent of the plugin function result (for RECORD and DYNAMIC ARRAY, the runtime system will do the JSON to BDL conversion automatically).

The second returned value is callback-id, the identifier returned by the callWithoutWaiting front call that is causing this result. For example, for a Media plugin front call, the callback-id can look like:
Media-messageChannel:0

If the result queue is empty, both result and callback-id are NULL.

In case of an error, the front call raises a runtime error -6333 that can be caught with TRY/CATCH or WHENEVER ERROR.
Note: Use the err_get() function, to identify the reason of the error. For more details about front call error handling, see ui.Interface.frontCall().

Example

DEFINE res, id STRING
CALL ui.Interface.frontCall("cordova", "getCallbackData",
        [], [res, id])