Why should one use the Dialogs API

Hi,
The title says it all, why should I use the Dialogs API to display
dialog windows?
I need to prevent the windows from being resized, for that I need a
workaround to the normal Dialogs API creation method, I can't control
the buttons I want, I know I can display some buttons but I'm never in
complete control over them. Designing the windows is not accurate as I
can't easily include the buttons added in the design, they are always
added at the bottom right area, what if I need a button to the left at
the same level?

A dialog created with the API is a normal awt Dialog, if it's just
because it is positioned at the centre of the screen, than I've been
doing that for so log in normal Java Applications that it isn't a
problem.

Bottom line, why is the Dialog API there and when should I use it?


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Best regards,

Sérgio Lopes