Waiting for an indeterminate process

Sometimes we are not able to get the information about the progress of a task. Therefore, we are not able to use the normal progress indicator that starts at 0.0 and ends at 1.0, because we don't have the value to be set to the progress indicator.

For example, we perform sophisticated calculations on the server (see the following screenshot) and we want to let the user know that something is happening on the server and the user should wait for the result.

How to do it...

Carry out the following steps:

1. Let's implement the price calculation. The calculation will be done in a separate thread and therefore we implement the Runnable interface and place the calculation code into the run() method.

   class PriceCalculation implements Runnable {
   
     private long calculated = 0;
     private final ProgressIndicator indicator;
     private final Label label;
   
     public PriceCalculation(ProgressIndicator indicator, Label label) {
       this.indicator = indicator;
       this.label ...