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Question

I have gone through lots of tutorials which teach about layouts in Java Swing, but they don't seem to suffice my need. I am creating a solar system GUI using Java Swing, and i want to place the planets in the GUI according to the values i fetch from my micro controller, which are usually float point values. I cannot use the Grid Bag Layout, as to position a label i have to specify grid x and grid y, which cannot be the case since I receive float point values from the micro controller. The best resource i found is to use absolute layout where i can specify the position of the planet by giving mere X and Y Co-ordinates, which will be fetched from the micro controller. The problem I am facing now is that the absolute layout does not have auto re-size feature.

What would be the best possible option to adopt the auto re-size feature in absolute layout?

Answer 1

Swing tutorials were not generally meant for situations like this -- they were meant for people who want to write more normal GUI applications, using buttons, drop-down boxes, check boxes, radio buttons, menus, and have layout that follows currently accepted practices in terms of positioning those on the screens. If any of that applies to the part of your program that is not displaying planets, I encourage you to use what they have to say about it.

But you want to place things according to calculations of your own. I recommend doing that in a panel, calculating the size and position of your objects according to the size of the panel at the point of drawing. When the panel resizes, you will need to trap the event that says it is resizing and redraw. You will need to deal with your own minimums and maximums, etc.

I don't recommend the custom layout manager suggested elsewhere for a couple of reasons. Firstly, it won't save you any work at all -- you are still going to have to write the code that determines positions of things, if you just then draw your own graphic instead of attempting to position a UI element, I think it will actually be less work. And that's the second reason -- layout managers' purpose is to position UI elements within the panel, and the pieces of your solar system don't really have any need to be UI elements, just graphics on the screen.

Good luck.