GUI-elements with funcionalities

I'm searching for classes that can represent classes (in the form of a rectangle with text in it that can be
moved with the mouse and that can invoke an action when doubleclicked upon) and relations (in the form
of lines and arrows that can be manipulated with the mouse). Can anyone tell me where I might find such
classes or which classes I might use to implement such classes?
Jeppe041198Asked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Jeppe041198Author Commented:
Edited text of question
0
dufortCommented:
This is a "classic" exemple of object-oriented programming. You will need to build a DrawCanvas class derivated from Component that owns a Vector of rectangular regions, each region represented with a DrawElement, a class derivated from Rectangle. Any drawable object (Oval, Line, Box, ...) inherits from DrawElement. When the user clicks anywhere on the DrawCanvas you must find if the click is inside() any of the DrawElements, and select (draw a rectangle on bounds()) the first matching object. Of course, you will need methods for changing the priority (or layers) of your drawn objects. Don't forget that low-layer objects are drawn first, but high-layer objects are selected first.

Add a TextField outside your work area for specifying the text tag for the selected DrawElement. Any such element can have a tag, even the arrows and lines. This is simpler like that.

Adding an object traced by the user at the end of your vector should not be difficult. Deleting the selected object is trivial.

May I suggest you taking a look into Microsoft Word's drawing tools. This should give you some hints on how to implement yours.

Let me know if you need more advices. I will have more time after 1998/04/24 to work on this.

0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Jeppe041198Author Commented:
The suggestion that you give is more or less the way I eventually did it, but now I have an other problem. I have several Panels in a Frame. Four of these Panels implement a KeyListener. My problem is  that when the DELETE-key is pressed after selecting a rectangle (more or less like your "DrawElement") this event is "caught" in the wrong panel...
0
dufortCommented:
Are you sure you gave the focus to the Panel where the Rectangle was selected? The component with focus recieves the key events. For some components, the focus is not given automatically and you must "force" it.

Try requestFocus() and if you're not sure check if your component hasFocus(). (I assume here  you're using Swing components, but it should work with standard AWT's as well).

0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Java

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.