G4P > two questions about Gwindow
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Contributed Library Questions
•
2 months ago
Hi everyone :^)
I have two questions.
First question is :
I have NPE problem. I've tried to solve by myself. But...
When I start my processing, usually it runs very well, but very very occasionally NPE occurs, not every time. To find the cause of NPE, I've used
println
almost everywhere in my code (I'm not sure whether it's a good way though). Now I guess that it occurs when Gwindow is initializing, because
println("after window");
didn't execute. Is it right? Then what should I do?
This
createControlWindow() method is located in void setup.
- void createControlWindow()
- {
- int cwHeight = ssh+cwh;
- println("ccw in : "+ssw+", "+cwHeight);
- window = new GWindow(this, "ControlWindow", 0, 100, ssw, cwHeight, false, JAVA2D);
- println("after window");
- window.setBackground(0);
- window.addDrawHandler(this, "windowDraw");
- window.addMouseHandler(this, "windowMouse");
- println("ccw end");
- }
ccw in : 1440, 426
java.lang.NullPointerException
at processing.core.PApplet.handleDraw(PApplet.java:2301)
at processing.core.PGraphicsJava2D.requestDraw(PGraphicsJava2D.java:243)
at processing.core.PApplet.run(PApplet.java:2141)
at java.lang.Thread.run(Thread.java:680)
Second question is :
As I've mentioned above I've used
println
almost everywhere in my code to find the cause of NPE. Then I've found out that
windowDraw (DrawHandler of Gwindow is called 'windowDraw'.) executes more often than
void draw. Can I make that
windowDraw executes only when
void draw executes? not more not less.
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