Class SpinnerValueFactory.DoubleSpinnerValueFactory

Note that the default converter is implemented simply as shown below, which may be adequate in many cases, but it is important for users to ensure that this suits their needs (and adjust when necessary). The main point to note is that this StringConverter embeds within it a DecimalFormat instance that shows the Double to two decimal places. This is used for both the toString and fromString methods:

 setConverter(new StringConverter<Double>() {
     private final DecimalFormat df = new DecimalFormat("#.##");

     @Override public String toString(Double value) {
         // If the specified value is null, return a zero-length String
         if (value == null) {
             return "";
         }

         return df.format(value);
     }

     @Override public Double fromString(String value) {
         try {
             // If the specified value is null or zero-length, return null
             if (value == null) {
                 return null;
             }

             value = value.trim();

             if (value.length() < 1) {
                 return null;
             }

             // Perform the requested parsing
             return df.parse(value).doubleValue();
         } catch (ParseException ex) {
             throw new RuntimeException(ex);
         }
     }
 });