Technical FAQ

From Processing

The bases

• What is a color in Processing?
• What are setup() and draw()?

Sequencing and timing

• I display images in sequence but I see only the last one. Why?
• How do I display a message for a few seconds?
• How to manage the steps of a game: increasing levels, displaying messages, etc.?

More advanced questions

• From several variables to arrays
• From several arrays to classes
• Why use ArrayList instead of array with append()?

Common problems

• Why I can't create a class of a library from my own classes?
• Common issues with sketch names

Exceptions

• What is an exception? (also explains the "Unhandled exception type XxxException" error)
• Why do I get a NullPointerException?
• Why do I get an ArrayIndexOutOfBoundsException?

See also Common Error Messages and Troubleshooting

Eclipse

• How I can make a sketch with libraries in Eclipse?