When the load operation has completed, callback will be called
with user data. To finish the operation, call
gio.file.File.loadContentsFinish with the #GAsyncResult returned by
the callback.
If cancellable is not null, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation
was cancelled, the error gio.types.IOErrorEnum.Cancelled will be returned.
Starts an asynchronous load of the file's contents.
For more details, see gio.file.File.loadContents which is the synchronous version of this call.
When the load operation has completed, callback will be called with user data. To finish the operation, call gio.file.File.loadContentsFinish with the #GAsyncResult returned by the callback.
If cancellable is not null, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error gio.types.IOErrorEnum.Cancelled will be returned.