Java 筆記

AWT, Graphics2D



1.
if add or remove something in frames, should call validate()/revalidate() to recalculate the layout
then call repaint() to paint the new canvas

2.
use btn flag and repaint() to ctrl the canvas scale/rotate/etc.

3.
how to direct paint Graphics2D objects?
Seems can not do this.

4.
class Area for the logic figure calculation