Hello everyone. I had a quick question. How can I go about setting constraitnts for a JTextField. I'm trying to not allow users to enter any non numeric numbers, except for dollar signs, commas and periods. Also how can I restrict a JTextField to only allowing two numbers to be entered. Like from 0-99. May someone give me an example to both please. Thanks in advance.
NycNessyness 0 Junior Poster in Training
jwenting 1,889 duckman Team Colleague
set up a KeyListener to it which refuses to allow anything you don't want.
NycNessyness 0 Junior Poster in Training
set up a KeyListener to it which refuses to allow anything you don't want.
May I get an example of how I would do that please. I don't know how to set up constraints at all. I don't really need it for what I'm doing but it would save me some trouble from throwing exceptions, unless the user copy and pastes the info into the textfield.
Ezzaral 2,714 Posting Sage Team Colleague Featured Poster
You can also use a JFormattedTextField: http://java.sun.com/docs/books/tutorial/uiswing/components/formattedtextfield.html
or an InputVerifier: http://java.sun.com/docs/books/tutorial/uiswing/misc/focus.html#inputVerification.
NycNessyness 0 Junior Poster in Training
You can also use a JFormattedTextField: http://java.sun.com/docs/books/tutorial/uiswing/components/formattedtextfield.html
or an InputVerifier: http://java.sun.com/docs/books/tutorial/uiswing/misc/focus.html#inputVerification.
Thanks alot!
NycNessyness 0 Junior Poster in Training
I tried some of the codes out and still couldn't find a solution. I'll give an example of what I'm trying to do. If I have a field named "JTextField num= new JTextField(10);", how can I make this particular field only accept number formats. It won't allow the user to input any letters at all before they even select enter.
Ezzaral 2,714 Posting Sage Team Colleague Featured Poster
Those things are covered by the tutorials that I linked above.
Ezzaral 2,714 Posting Sage Team Colleague Featured Poster
If you don't want to allow them to even type anything but numbers into field, you need to use the MaskFormatter: http://java.sun.com/docs/books/tutorial/uiswing/components/formattedtextfield.html#maskformatter
(Which you will see is covered in the first link I posted above on using JFormattedTextField)
NycNessyness 0 Junior Poster in Training
If you don't want to allow them to even type anything but numbers into field, you need to use the MaskFormatter: http://java.sun.com/docs/books/tutorial/uiswing/components/formattedtextfield.html#maskformatter
(Which you will see is covered in the first link I posted above on using JFormattedTextField)
I looked through it, worked perfectly. Thanks alot for the help!
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