Java GUI why does the window appear in the top left corner on Linux Kubuntu?

Question

Java

I create a window using JFrame, set the window size and position, but every time the program starts, the window appears in the upper left corner, as in the screenshot. Sometimes, but very rarely, everything appears as it should. What could be the problem and how to fix it? Everything works on Windows.

Answer 1

Try putting it setVisible()at the end.
Also try putting everything inside SwingUtilities.invokeAndWait(), SwingUtilities.invokeLater(). In theory, all methods that update the GUI should be called like this.