Make JSpinner completely numeric

Question

I've a Jspinner that can vary from minimum to maximum at steps of 0.1. This is working perfectly fine. Now, I set the editor of JSpinner as NumberEditor as the user can edit the textbox and I want only numeric values from this. This is also working, that is whatever the user may enter, the editor gives me only the numbers in the editor when I get the value using mySpinner.getValue().toString();. Now cones the problem. I want the textbox to accept only numeric values and .(decimal point), that is, if the user tries to enter anything apart from 0-9 and ., it should not echo it in the textbox.

JSpinner mySpinner = new JSpinner();
mySpinner.setModel(new SpinnerNumberModel(default,minimum,maximum,0.1));
mySpinner.setEditor(new JSpinner.NumberEditor(mySpinner,"##.#"));

Can someone help me with this. Thanks :)

Stun

are you read my comments to your post from yesterday – Regress

ya, I read it, I can increment and decrement in steps on 0.1, that problem was solved. Thanks :) – Stun

Answer 1

You could try setAllowsInvalid(false) as follows:

JFormattedTextField txt = ((JSpinner.NumberEditor) mySpinner.getEditor()).getTextField();
((NumberFormatter) txt.getFormatter()).setAllowsInvalid(false);

By setting this property, the Jspinner will show only valid values in the field and ignores all other values entered by the user. also the user will not be able to delete the whole value entered in the Jspinner i.e. if the user tries to select the entire value and delete it will not be allowed. User can edit the field only with a valid value other wise the it will seem like un-editable.

Ranice

So, after doing this, should I do anything to link this with my JSpinner's testbox? – Stun

Like this doesnt allow me to input characters, but the problem is, this doesnt allow me to input . also, which I need, and I cant clear the field, requires at least one number in it all the time , is this a property of the JFormattedTextField – Stun

yes you cant clear the field but you can set the correct format for the field as below: NumberFormatter formatter = (NumberFormatter) txt.getFormatter(); DecimalFormat decimalFormat = new DecimalFormat("0.0"); formatter.setFormat(decimalFormat); formatter.setAllowsInvalid(false); – Ranice

The above solution will allow to input . and to clear the field refer link – Ranice

Work perfectly 👌 – Thorbert