Show progressDialog for 2 seconds while waiting for a thread to finish

Question

I have an activity in which I call a service that can take a while to complete and until that service didn't finish, the menu options that are clicked should return an error message like "data not yet ready, please try again soon" however, I want to give it a couple of seconds to finish before I throw that error and during that time, I want to show a progressdialog on the screen. here is the code that I have:

if(calculatedValue.equals(NOT_YET_CALCULATED)){
                //show progress dialog
                ProgressDialog progress = ProgressDialog.show(this, "", getResources().getString(R.string.wait), true);
                long timeStarted = System.currentTimeMillis();
                while(calculatedValue.equals(NOT_YET_CALCULATED) && System.currentTimeMillis() - timeStarted < 1500){
                    // wait for at most 1.5 seconds
                }
                progress.dismiss();
                if(calculatedValue.equals(NOT_YET_CALCULATED)){
                    //if it's still not there, there's probably a problem, show generic alert dialog
                    AlertDialog dialog = new AlertDialog.Builder(this).create();
                    dialog.setTitle(R.string.not_yet_calulated_alert_title);
                    dialog.setMessage(getResources().getString(R.string.not_yet_calulated_alert_message));
                    dialog.show();
                }else{
                    startActivity(j);
                }
            }else{
                startActivity(j);
            }

Let me explain: I check if the value exists, and if it doesn't I show a progress icon (i'm going for the circle thingy) for 1.5 seconds. If after that time it's still not there, I give up and show an error message.

The problem is that the progress thing does not show up on the screen. what am I doing wrong?

thanks, e.

Answer 1

figured it out, should use async task for this, here's the code:

    if(calculatedValue.equals(NOT_YET_CALCULATED)){
    //show progress dialog
    final ProgressDialog progress = ProgressDialog.show(this, "", getResources().getString(R.string.wait), true);
    AsyncTask<Void, Void, Boolean> waitForCompletion = new AsyncTask<Void, Void, Boolean>(){
        @Override
        protected Boolean doInBackground(Void... params) {
            long timeStarted = System.currentTimeMillis();
            while(calculatedValue.equals(NOT_YET_CALCULATED) && System.currentTimeMillis() - timeStarted < 1500){
                // wait for 1.5 ms
                 try {
                        Thread.sleep(100);
                    } catch (InterruptedException e) {
                        Log.e(TAG, "thread interrupted", e);
                    }
            }
            progress.dismiss();
            return calculatedValue.equals(NOT_YET_CALCULATED);
        };
        @Override
        protected void onPostExecute(Boolean result) {
        if(result == true){
            AlertDialog dialog = new AlertDialog.Builder(TodayActivity.this).create();
            dialog.setTitle(R.string.not_yet_calulated_alert_title);
            dialog.setMessage(getResources().getString(R.string.not_yet_calulated_alert_message));
            dialog.show();
        }else{
            i.putExtra(Constants.AMOUNT, Integer.parseInt(calculatedValue));
            startActivity(i);
        }
        }
    };
    waitForCompletion.execute(null, null, null);
}else{
i.putExtra(Constants.AMOUNT, Integer.parseInt(calculatedValue));
startActivity(i);
}

Answer 2

What you are making now atleast causes a deadlock.

What I normally do is creating the progressdialog as you are doing now and on the same time start another thread that in this situation waits for 1.5second and stop the progressdialog then.

For example

    private Runnable waitforcompletion = new Runnable()
{
    @Override
    public void run()
    {
         while(calculatedValue.equals(NOT_YET_CALCULATED) && System.currentTimeMillis() - timeStarted < 1500){
                Thread.sleep(10);
                }

                progress.dismiss(); 
    }
};

And for starting just call the above runnable after creating the progressdialog