Thread: Please help

I have a big problem when creating the calculator in Jcreator.the thing is after running the program, when I press the decimal point for anytime(even more than once) it displays in the text field.I tried to solve this & failed.please can some one give me a solution for this.It's better if you can provide me the codings.

If you want to ignore the decimal point key if there is already a decimal point displayed in the text field, use a DocumentFilter, something like this:

...
JTextField textField = new JTextField();
PlainDocument doc = new PlainDocument();     // or whatever document type you require
 
doc.setDocumentFilter(new DocumentFilter() {
    @Override
    public void replace(FilterBypass fb, int offset, int length, String text, AttributeSet attrs)
            throws BadLocationException
    {
        // get document text
        Document currentDoc = fb.getDocument();
        String docText = currentDoc.getText(0, currentDoc.getLength());
 
        // return if both current and new text have a decimal point
        if (text.contains(".") && docText.contains(".")) {
            System.out.println("Decimal point already entered!");
            return;
        }
        // allow the new text
        super.replace(fb, offset, length, text, attrs);
    }
});
textField.setDocument(doc);

If that's not what you wanted, you'll have to explain a bit more clearly.

Originally Posted by prasansani

I have a big problem when creating the calculator in Jcreator.the thing is after running the program, when I press the decimal point for anytime(even more than once) it displays in the text field.I tried to solve this & failed.please can some one give me a solution for this.It's better if you can provide me the codings.

Well, you could try to get it to reset the TF to zero if it's pushed more than once or something.

Also, what's wrong with that? Just make sure it'll output "Error" or something if the user does that.