This function will normally be called for you automatically by Android.App.LoaderManager when the associated fragment/activity is being started. When using a Loader with Android.App.LoaderManager, you must not call this method yourself, or you will conflict with its management of the Loader. Starts an asynchronous load of the Loader's data. When the result is ready the callbacks will be called on the process's main thread. If a previous load has been completed and is still valid the result may be passed to the callbacks immediately. The loader will monitor the source of the data set and may deliver future callbacks if the source changes. Calling Loader.StopLoading will stop the delivery of callbacks.
This updates the Loader's internal state so that Loader.IsStarted and Loader.IsReset will return the correct values, and then calls the implementation's Loader.OnStartLoading.
Must be called from the process's main thread.