Avoiding JSpinner to take letters

问题

I have a jSpinner with a SpinnerNumberModel like this:

spinnerModelFix = new SpinnerNumberModel(0, 0, 65535, 1);
JSpinner fixedValueSpinner = new JSpinner(spinnerModelFix);

I just want to show Integers in the spinner, so that if the user insert letters they aren't shown.

I thought I should extends SpinnerNumberModel and override the fireStateChanged() method...

But I'm not sure what I need to do in that method.

Can anyone give me some hint?

回答1:

• yes is possible and workaround is quite simple,

• there are two ways how to do it, have to derive JTextField or JFormattedTextField from JSpinner,

• then to add

  a) DocumentListener

  b) DocumentFilter

I think that usage of DocumentFilter is easiest for code workaround, better, maybe safer

回答2:

You can try setAllowsInvalid(false) on spinner's formatter. For example:

SpinnerNumberModel spinnerModelFix = new SpinnerNumberModel(0, 0, 65535, 1);
JSpinner fixedValueSpinner = new JSpinner(spinnerModelFix);
JFormattedTextField textField = ((JSpinner.NumberEditor) fixedValueSpinner
        .getEditor()).getTextField();
((NumberFormatter) textField.getFormatter()).setAllowsInvalid(false);

来源：https://stackoverflow.com/questions/12825622/avoiding-jspinner-to-take-letters