SwiftUI – How to disable window resizability in macOS 11 and 12

Question

Crudgle OP

Created Mar ’25

Replies 2

Boosts 0

Participants 2

My app needs to run on macOS 11+. It has one window of fixed size i.e. it should NOT be resizable.

.windowResizability(.contentSize) is only available in macOS 13+.

How can window resizability be disabled in macOS 11 and 12 ?

I'm running Xcode 16.2 on macOS 15.3.2.

Thanks.

Answered by B347 in 829392022

Hi, did you check with this: I know its AppKit based, but you can mix&match both Frameworks.

[https://developer.apple.com/documentation/appkit/nswindow/stylemask-swift.property)

[https://developer.apple.com/documentation/appkit/nswindow/stylemask-swift.struct)

if let window = NSApplication.shared.windows.first {
    window.styleMask.remove(.resizable)
    window.setContentSize(NSSize(
        width: 400, 
        height: 400)
    )
}

Boost

Answer 1

B347 OP

Mar ’25

Accepted Answer

Hi, did you check with this: I know its AppKit based, but you can mix&match both Frameworks.

[https://developer.apple.com/documentation/appkit/nswindow/stylemask-swift.property)

[https://developer.apple.com/documentation/appkit/nswindow/stylemask-swift.struct)

if let window = NSApplication.shared.windows.first {
    window.styleMask.remove(.resizable)
    window.setContentSize(NSSize(
        width: 400, 
        height: 400)
    )
}

0

Answer 2

Crudgle OP

Mar ’25

B347, many thanks.

Yes, I did try stylemask but tried different forms:

.styleMask.subtract(.resizable)
NSWindow.styleMask.remove(.resizable)
Window.styleMask.remove(.resizable)

Naturally, all my attempts resulted in errors.

My app doesn't import AppKit as yet so, I'll just restrict it to running on macOS 13+.

It's very early days for me.

0