Solved

Image flicker

Posted on 2002-06-05
5
270 Views
Last Modified: 2010-03-31
I have written an applet that does banner rotation. The only thing is that the banners flicker, as though they are being redrawn by clearing to the background first. It doesn't matter whether the banner is animated of not and it is not occuring at the point when the banner image is changed.

My paint method looks as follows

     public void paint(Graphics g)
     {
          Image image=getImage(u[current_image]);
          g.drawImage(image,0,0,this);
     }

Just to make sure I used Mediatracker to ensure the image was loaded, but this had no effect.

Any clues how I can overcome this?
0
Comment
Question by:mouatts
  • 3
  • 2
5 Comments
 
LVL 16

Accepted Solution

by:
imladris earned 50 total points
ID: 7057489
In your applet, you need to override the update method. In the same class that contains the paint method, provide an override for the update method like:

public void update(Graphics g)
{   paint(g);
    return;
}


This needs to be done to avoid the flicker because the default update does exactly what you suspected. It clears the image by redrawing the background first.
0
 
LVL 11

Author Comment

by:mouatts
ID: 7058268
Thanks that sort of did the trick, there was another wrinkle that someone else might have mentioned had you not locked the question!
0
 
LVL 16

Expert Comment

by:imladris
ID: 7059476
For the sake of the value of the PAQ's, it would be nice if you mentioned what the wrinkle was.

If you dislike questions being "locked" (which does not in fact prevent anyone from adding comments), you could mention that in the question or reject the answer.

The guideline for answers below notes that an answer should be "a specific solution to a question ... [that] will solve the questioner's problem and doesn't duplicate a previous comment".
The answer I gave obviously did not duplicate a comment, and it was my conviction that it would solve your problem. There is always the possibilty that I am wrong, of course, which is why you have access to the "reject answer" button.
0
 
LVL 16

Expert Comment

by:imladris
ID: 7059486
P.S. there is an extensive debate on the topic of answers and comments at: http://www.experts-exchange.com/expinput/Q_20304200.html .
0
 
LVL 11

Author Comment

by:mouatts
ID: 7059529
You've been on EE long enough to know that locking questions is frowned on by the vast majority of members.

The wrinkle is of course dealing with the situation when you do want to repaint the background. The answer of course being to use super.update(g) on those occasions.
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
groupNoAdj 7 87
Which is the latest version of Apache Tomcatl 3 51
jar file executable 12 44
javap bin 2 30
An old method to applying the Singleton pattern in your Java code is to check if a static instance, defined in the same class that needs to be instantiated once and only once, is null and then create a new instance; otherwise, the pre-existing insta…
By the end of 1980s, object oriented programming using languages like C++, Simula69 and ObjectPascal gained momentum. It looked like programmers finally found the perfect language. C++ successfully combined the object oriented principles of Simula w…
Video by: Michael
Viewers learn about how to reduce the potential repetitiveness of coding in main by developing methods to perform specific tasks for their program. Additionally, objects are introduced for the purpose of learning how to call methods in Java. Define …
The viewer will learn how to implement Singleton Design Pattern in Java.

863 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

21 Experts available now in Live!

Get 1:1 Help Now