Java: GUI Tips
[Beginning of list of GUI tips -- needs much more]
Program structure
main can be in any class, but it's often
simplest to understand if it's in a separate class.
main should do very little work -- typically
this means just create a window (JFrame) and
display it.
- A graphics panel should be a subclass of
JPanel
and override paintComponent.
- A graphics panel may be declared inside an
the enclosing panel or window class so that it may
use the instance variables of the outer class.
Events and communication
After the GUI is constructed, the program stops execution until
the user does something that causes listener to called.
- Instance variables are the way a listener typically
communications changes.
- Listener methods (eg,
actionPerformed)
may be mixed in with the GUI construction code. This makes
the code hard to understand. Define methods that these listeners
call and put those methods in one place, so the GUI construction
can be separated from the GUI execution.
Building the GUI
- Do not add elements to a layout after the GUI has already
been started. If you want to display a different layout
of components, use a
JTabbedPane or
CardLayout.