getCallbackHandle static method

CallbackHandle? getCallbackHandle(
  1. Function callback
)

Get a handle to a named top-level or static callback function which can be easily passed between isolates.

The callback argument must not be null.

Returns a CallbackHandle that can be provided to PluginUtilities.getCallbackFromHandle to retrieve a tear-off of the original callback. If callback is not a top-level or static function, null is returned.

Implementation

static CallbackHandle? getCallbackHandle(Function callback) {
  return _forwardCache.putIfAbsent(callback, () {
    final int? handle = _getCallbackHandle(callback);
    return handle != null ? CallbackHandle.fromRawHandle(handle) : null;
  });
}