get(0,'Mon​itorPositi​ons') outputs wrong values

Hello,

I have a big issue with the outputs from

get(0,'MonitorPositions')

when the screen is changed within one MATLAB session!

For example:

I start my PC and run my Monitors at my standard resolution. Then I type

get(0,'MonitorPositions')

and it is just fine.

But when i plug in a projector for example or change the resolution of my screen and just run the same code

get(0,'MonitorPositions')

then it outputs the same values like before even though the resolution obviously changed!

I have written a function that needs the correct resolution of the attached displays, but now it is just a desaster.

Hope someone can help me.

Answer 1

[Adam Danz]

As stated in the documentation (<- link),

MATLAB® sets the display information values for this property at startup. The values are static. If your system display settings change, the values do not update. To refresh the values, restart MATLAB.

Perhaps this API will come in handy: https://www.mathworks.com/matlabcentral/fileexchange/31437-windowapi

[Z.P.]

Thank You, this sounds logical but MATLAB somehow must get those values also when it starts. I mean, if they can do this then it must be possible, (somehow).

[Image Analyst]

Yes but I guess they don't expose that internal function call for us to use, and also don't set it up to automatically receive a message that the screen configuration has changed. Thus it seems you have to use an API call to do it yourself when you think you need to. Not ideal but it is what it is.

[Stephen23]

"...also don't set it up to automatically receive a message that the screen configuration has changed."

I very doubt that this is trivial to achieve on a multi-OS application.

[adams13]

In R2024b under Windows 11, get(0, 'MonitorPositions') looks to dynamically reflect the change, even without restarting MATLAB. After I connect or disconnect an additional monitor, the next call shows correct number of monitors.