how to use GDI wiht QT to show a picture on the secondary Screen（or Projector），if dont extend these displays？

[jimfar]

how to use GDI wiht QT to show a picture on the secondary Screen（or Projector），if dont extend these displays？

[SGaist]

Hi,

Can you give more details about your setup and your goal ?

[jimfar]

i dont want extend displays when The PC exist two or more screen,and it can draw a picture on the secondary Screen non primary screen . so what should i do ?

[SGaist]

Sorry but it's not any clearer. Qt applications are not tied to a monitor so if you have two you can have widgets of on application on the two screens.

If it's not what you are looking for, you should describe exactly your setup and the goal of your application.

[jimfar]

when the PC exist mutil scree on one display card, i wanna show a picture on the non primary screen ,and the screen dont show anythine but the picture, even if dragging a windows into this screen from the main screen .

[JKSH]

@jimfar said in how to use GDI wiht QT to show a picture on the secondary Screen（or Projector），if dont extend these displays？:

i dont want extend displays

When you say "Extend", do you mean this?:

If so, I'm not sure it's possible. If you don't extend, then Qt only sees 1 screen.

Do you know of any other software that can show a picture on a secondary screen without extending?

[jimfar]

yes ，it is what i mean.
if it can use GDI to complete these work

[JKSH]

@jimfar said in how to use GDI wiht QT to show a picture on the secondary Screen（or Projector），if dont extend these displays？:

yes ，it is what i mean.

As I said: If you don't extend, then Qt cannot see your secondary screen.

if it can use GDI to complete these work

Then you must call GDI functions in your program: https://docs.microsoft.com/en-us/windows/win32/gdi/windows-gdi

[jimfar]

ok thanks