JFrame scaling for high resolution screens

Question

I have a non resizable Jframe of size 1280x800. Of course this size appears bigger and smaller according to the resolution of the screen. (It has a background image). Now, if i try this on lets say a 4k monitor, it would be absolutely impractical because to small. Isn't there a way to scale the JFrame? Or a solution to this problem? What i thought i would do is write bigger jFrames and tell the main class which one to open according to the resolution. I am sure there is a much more elegant way to do that, since i guess it is a problem that many would have come across! What a nightmare! Please help me! Thank you

Answer 1

One way you could achieve that is by getting the screen size of the device, and then setting the size of your JFrame accordingly:

Dimension screenDimension = Toolkit.getDefaultToolkit().getScreenSize();
double jFrameWidth = screenDimension.width * 0.7;
double jFrameHeight = screenDimension.height * 0.5;

Or if you just want to maximise the JFrame you can use:

jFrame.setExtendedState(JFrame.MAXIMIZED_BOTH);

Answer 2

Detect the resolution of the window you're launching on and scale the frame to a percentage of that window. Have a baseline dimension (1280 * 800) so it isn't too-squashed on smaller screens.

As an example I pull the local GraphicsEnvironment, I pull the data from each relevant GraphicsDevice into a data class that I wrote myself, and I use that throughout my project as it gives me all sorts of stuff like buffer strategies, window dimensions, and so on. I do this when the application is loading (using a SplashScreen) which affords me control over the whole process.

That's about as elegant as you can get, I think.

---

EDIT

Editing in some example pseudocode to give an idea of what I'm getting at. I write primarily in Java, but I'm not doing this in an IDE so it won't necessarily be compile-ready:

public void scaleWindowDimensions(JFrame frame, GraphicsDevice gd) {
    Rectangle bounds = gd.getDefaultConfiguration().getBounds();
    int screenX = (int) bounds.getWidth();
    int screenY = (int) bounds.getHeight();
    // substitute this for however you're setting the size of the JFrame; this is simply how I sometimes do it
    frame.getContentPane().setPreferredSize(new Dimension(screenX, screenY));
}

This is a very quick example that will set the size of your JFrame to that of the monitor it's running on. You'll need to modify the background image you're using as well. There's a lot more you could do with this but I'm keeping it simple on purpose.