Android AsyncTask - Using "Void, Void, Void" parameters (code signature)

As a quick note to self, this is how I just created an Android AsyncTask with “Void, Void, Void” parameters:

private class DeleteImagesTask extends AsyncTask<Void, Void, Void> {

     * `doInBackground` is run on a separate, background thread
     * (not on the main/ui thread). DO NOT try to update the ui
     * from here.
    protected Void doInBackground(Void... params) {
        return null;

     * `onPostExecute` is run after `doInBackground`, and it's
     * run on the main/ui thread, so you it's safe to update ui
     * components from it. (this is the correct way to update ui
     * components.)
    protected void onPostExecute(Void param) {

I call this AsyncTask like this:

private void handleDeleteSelectedImagesProcess() {
    new DeleteImagesTask().execute();

For the purposes of this short tutorial it doesn’t matter what that code does; I just wanted to show how to implement an AsyncTask with Void/null parameters, i.e., the class and method signatures. This is one of those (weird) cases where I didn’t want/need to pass any data to/from the AsyncTask, I just needed to run “something” that didn’t require any input parameters, and I didn’t need any output parameters (results) back from it.

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