I don't know if there will be a good practice for this, since I have a screen with a JMenu with many items
->Menu
->Usuario
{
->Iniciar sesion
->Registrarse
->Informacion de usuario
}
->Ayuda
{
-> Instrucciones de juego
-> Acerca del juego
}
So I create a JFrame Form for each of these if needed, registration window, login window, information window, help window, etc. And I don't know if this is a common practice or if there is a more practical way to work this.
I think it could be a bad practice if when opening a new window the other stays open as it would be uncomfortable for the user, what you could do in this case would be to have a JPanel for each option you mention and load the JPanel that is required in a single JFrame . Also if you prefer you can use a JTabbedPane (tabs) in a JFrame and thus have all the options in a single JFrame.
In deciding how you handle windowing in an application there is no best practice. If you compare for example the old Freehand or the Gimp with Photoshop, you realize that some applications use multiple main windows (which has its advantages for example on systems with multiple screens) and others manage this distribution of windows by tabs or docks.
That said, if there are good alternatives to creating multiples
JFrame
that can be considered. Most of these alternatives are based onJPane
a layout.Bad practice is only what doesn't work or makes your users jump out of the window (or throw their equipment out of it).