Question

I have created a splash screen for my app to hide the periodic insertion (after publishing updates) of a large number of records into the different tables of my app’s SQLite database. I have been implementing an AsyncTask to handle the insertion off of the UI thread.

I need to create a ProgressDialog (with progress bar, not the simple spinning wheel) to inform the user of the current progress percentage for the insertion operations.

In most examples for setting the dialog’s progress bar, the counter variable for the for loop representing the lengthy operation, or the percentage of file download is used to set this progress for the dialog. However, since insertions into different tables may take different amounts of time (depending on number of columns, etc), this approach appears to fail. The closest solution I could see would be to write a publishProgress(some_percentage) line after every record insertion in my doInBackground() method, using the % of records inserted as the parameter for publishProgress(), but this seems like a terribly inelegant and inefficient practice.

The current code for my AsyncTask implementation is below. Any suggestions for the best practice of determining the current progress percentage would be greatly appreciated. Thanks!

private class InsertionAction extends AsyncTask<Void,Integer,Void> {

    Context context;
    private ProgressDialog dialog;

    private ForwardAction(Context context) {
        this.context = context;
        dialog = new ProgressDialog(context);

    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();

        this.dialog.setMessage("Initializing Database. Please Wait...");
        this.dialog.show();
        this.dialog.getWindow().setGravity(Gravity.BOTTOM);
        this.dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
        this.dialog.setCancelable(false);
    }

    @Override
    protected Void doInBackground(Void... params) {

            // Large block of record insertions


        return null;
    }

    @Override
    protected void onPostExecute(Void aVoid) {
        super.onPostExecute(aVoid);

        // Forward to the main activity
        if (dialog.isShowing()) {
            dialog.dismiss();
        }

        animatedTransition(SPLASH_DISPLAY_TIME/2);
    }

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

}

Answer 1

Unfortunately there is no way to programmatically count your lines of code, calculate how much time they need to execute and generate an accurate time-proportionate progress.

I suggest updating the progress bar after a certain interval of lines, e.g. every 90 inserts (10%).

Or update according to what you are doing and modify the progress message (try to be creative), e.g. “Adding users”, “Generating death rays”, “Creating the universe”, “Just a little longer”, etc.