I'm currently working on a small project for school. I need to place a variable amount of checkboxes in a jPanel, but I have no idea how to start .
My first tought was to create an array of checkboxes, but this doesn't seem to work .

Any ideas ?

You can stick them in an array to keep track of them (though if it's variable, I would use Vector<JCheckBox> to store them. Then just iterate across the array to add them to the form.

Can't you use an arrayList or something to store checkbox objects (and add them and such)?

I am not sure as I haven't ever done any GUI programming in java, so I don't know too much about it, but I would assume you could use an arrayList to store the objects and keep track of them somehow?

I think the cold classroom was freezing my brains a bit . It is possible to create an array of checkboxes and I did it this way (it's still very basic):




Still don't know why it didn't work this morning

@ethergeek: I know vectors are more dynamic then arrays, but are there any other advantagen when using them ?

Lots.

• They're thread safe
• They're easier to work with
• Parameterized, there's no casting needed like there was in 1.4-
• Serialize easier
• Implement most of the collections interfaces, so you get sorting, iterating, serialization...right out of the box
• Built in batch methods for adding collections to collections

Object oriented collections almost always have an advantage over simple collections like arrays. The notable exception here is arrays of primitives...you can't make collections of primitives, so the JVM has to autobox/unbox them when you try...this can be slow if done in a large loop.

Edit: I forgot to mention: when updating a GUI on the fly, it's a good idea to pass it off to the Event Dispatch Thread (EDT) so as to avoid painting inconsistencies. This is easily done using the SwingUtilities.invokeAndWait() method.

This post has been edited by ethergeek: Nov 5 2007, 05:55 PM

Allright, crap , I still have a lot of things to learn about java , EDT, serlialization ...

I think I'll spend my weekend reading, reading and more reading

//edit: as soon as I've found out how to use vector, I'll implement them in my program , don't want to write a crappy project, going for at least 18/20

This post has been edited by wutske: Nov 7 2007, 08:13 AM

I have no idea what is the vector thing, but I'd go for an ArrayList<JCheckBox>. It's as dynamic as you'd need.

for example:

Adding a checkbox will result in:
1. extending the gui screen a bit more
2. adding the checkbox to the ArrayList
3. adding the checkbox to the gui.
etc.

Moo64c, this topic is almost one year old, I've turned the application in a long time ago .
Also, watch out for bumping old topics, the mods don't like it if you do it too often