NSAlert() runmodal 此 class 不符合键 modalWindow 的键值编码

Question

Recently i upgraded my mac to Catalina and seeing weird issues with NSAlert().

When ever any alert is opened i am getting bellow error in console and the alert is automatically closing, without any user clicking on OK button.

Error in console:

this class is not key value coding-compliant for the key modalWindow.' with user dictionary {
    NSTargetObjectUserInfoKey = "<ProjectName.AppDelegate: 0x100b07400>";
    NSUnknownUserInfoKey = modalWindow;
} 

Below is my code for displaying Alert.

let myPopup: NSAlert = NSAlert()
myPopup.messageText = messageText
myPopup.informativeText = infoText
myPopup.alertStyle = NSAlert.Style.warning
myPopup.addButton(withTitle: NSLocalizedString("OK", comment: "Button Text"))
let res = myPopup.runModal()

FYI: This is Mac App, using swift, Xcode11 (tried with Xcode 11.1 & 11.2)

Answer 1

Finally figured it,

In my application we do support for scripting so i added below code in AppDelegate file:

func application(_ sender: NSApplication, delegateHandlesKey key: String) -> Bool {
    return true
}

Since i am returning true always it is creating issues with NSOpenPanels, NSSavePanels and NSAlert, and i changed the code as below and it is working fine without any issues.

func application(_ sender: NSApplication, delegateHandlesKey key: String) -> Bool {
        if key == "[.sdf file KEY HERE]"{
            return true
        }
        return false
}

Please note i am getting this issues only in latest OS Catalina, in previous OS i didn't got any issues.