Centre window on leftmost screen with multiple monitors

[Don Kiddick]

Hi,
Our user have multiple screens and I wanted to centre a JFrame on the leftmost of these screens. Unfortunately the display drivers we are using appear to represent the screen size as one large screen. i.e it represents 3* 1024 * 768 screens as 1 * 3072 * 768 screen.
I have tried :

GraphicsEnvironment.getLocalGraphicsEnvironment().getScreenDevices().length 

but this returns one.
Anyone have any idea how I can display a window centred on the leftmost screen in such circumstances. Note users can have 1-6 screens.
thanks,
D
[ October 15, 2003: Message edited by: Don Kiddick ]

[Nathan Pruett]

If you know that they're going to be running in 1024 x 768 resolution then it's a simple matter of using a formula like this -

 
    Frame frame = //whatever
    int fullWidth = Toolkit.getDefaultToolkit().getScreenSize().width;
    int x = fullWidth - ( ( 1024 - frame.getSize().width ) / 2 );
    int y = ( 768 - frame.getSize().height ) / 2;
    frame.setLocation( x, y );

If their resolution can be variable as well as the number of monitors, you are basically going to have to guess. But you can make an educated guess - If you get a height of 480, the width is probably 640. If you get a height of 600, the width is probably 800. If you get a height of 768 the width is probably 1024, etc. You could also try to validate your guess a bit more by dividing the total screen width by the guessed width using modulus (%) and checking to make sure the result is 0.

[Don Kiddick]

cheers Nate, very helpful