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Whole screen flickers

Mika Leino
Ranch Hand

Joined: Jan 07, 2002
Posts: 56
I was wondering if anyone else has come across this peculiar thing. I have an applet which shows our client's products in a tree construct. The applet runs fine in all other machines, but on a particular computer there is some odd behaviour.
When ever the user goes to a page that contains the applet his screen starts to flicker. Not just the applet, but the whole screen. At one point it even when totally black, as if the screen's cable had lost contact for a second. And no, the cabling is OK, and all other pages display fine on his browser.
Here are some specs about the client's set up:
The computer is a Dell Latitude C810 laptop which is docked at the office. It has a Pentium III 1,23 GHz and 512 Mb of RAM. The OS is Windows XP and the browser is IE 6. The Java version is Sun JRE 1.4.1_01.
The applet has been implemented using swing classes.
I have absolutely no idea what is causing this so I was stumped when the client demonstrated this behaviour. Is this something the JRE does or is it something in the laptop? My guess would be the latter, but any input is most welcome.
[ September 16, 2003: Message edited by: Mika Leino ]

Mika Leino<br />SCJP, SCWCD
Rob Ross

Joined: Jan 07, 2002
Posts: 2205
It seems likely that the problem lies with some specific configuration of the laptop. What are the color settings of that user's environment? Does he have some non-standard color palette installed? That might cause color shifts when the applet comes to the front and changes the installed pallet to a "normal" web-safe one.
Another possibility is to check the laptop's Display control panel and play with any "acceleration" controls. If they're on, turn them off; or vice-versa. JDK 1.4 introduced hardware acceleration but some graphics cards may not play nice yet with the JDK's graphic optimizations.

SCJP 1.4
I agree. Here's the link:
subject: Whole screen flickers
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