android-asynctask-demo.java

public static void main(String... args) {

	AsyncTask<String, Integer, Boolean> task = new AsyncTask<String, Integer, Boolean>() {

		// loading dialog
		AlertDialog dialog = (new AlertDialog.Builder(context)).setCancelable(false).setMessage("loading").create();

		@Override
		protected Boolean doInBackground(String... strings) {

			publishProgress(1);

			doHttp1();

			publishProgress(2);

			doHttp2();

			publishProgress(3);

			doHttp3();

			publishProgress(4);

			return true;
		}

		@Override
		protected void onPostExecute(Boolean aBoolean) {

			super.onPostExecute(aBoolean);

			// todo
		}

		@Override
		protected void onProgressUpdate(Integer... values) {

			super.onProgressUpdate(values);

			switch (values[0]) {

				case 1:

					dialog.show();

				case 2:
				case 3:

					dialog.setMessage("progress " + values[0]);

					break;

				case 4:
				default:

					dialog.dismiss();
			}
		}

		private void doHttp1() {
			// do http request
		}

		private void doHttp2() {
			// do http request
		}

		private void doHttp3() {
			// do http request
		}
	};
}