Detect if monitor is rotated

Question

I have an application in JavaSE and i want my application always starts at center of screen. If two monitors are plugged, the right one should be used. So i wrote a code like this:

GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
if(ge.getScreenDevices().length == 2) {
    int w_1 = ge.getScreenDevices()[0].getDisplayMode().getWidth();
    int h_1 = ge.getScreenDevices()[0].getDisplayMode().getHeight();
    int w_2 = ge.getScreenDevices()[1].getDisplayMode().getWidth();
    int h_2 = ge.getScreenDevices()[1].getDisplayMode().getHeight();


    int x = w_1 + w_2  / 2 - getWidth() / 2;
    int y = h_2 / 2 - getHeight() / 2;

    setLocation(x, y);
}

Unfortunately if monitor is rotated at 90°, width and height should be flipped. Is there any way to detect such rotation?

Answer 1

You don't need to know whether the second monitor is in portrait mode. Just find the bounds of the screen in device coordinates and use the center. (If it is in portrait mode, then height>width, but that isn't an important piece of information.)

Your formula to determine the center point of the second device is wrong. You are assuming that the coordinates of the second screen runs from (w_1,0) to (w_1 + w_2, h_2), but that isn't necessarily true. You need to find the GraphicsConfiguration object of the second screen and call GraphicsConfiguration.getBounds() on it. You can then calculate the center point of that rectangle.

If you want to know which device is on the left or the right (or top or bottom), you can compare the x (or y) values of their bounding rectangles. Note that the x or y values may be negative.