Code=3072 "The operation was cancelled" when setting alternate app icon

I am trying to set an alternate app icon named MyIcon in my iOS app. I have a MyIcon.png image in my project bundle (not in my Assets folder) and it is declared in my Info.plist like so:

<key>CFBundleIcons</key>
<dict>
    <key>CFBundleAlternateIcons</key>
    <dict>
        <key>MyIcon</key>
        <dict>
            <key>CFBundleIconFiles</key>
            <array>
                <string>MyIcon</string>
            </array>
            <key>UIPrerenderedIcon</key>
            <false/>
        </dict>
    </dict>
</dict>

In my code, I try to change the app icon:

UIApplication.shared.setAlternateIconName("MyIcon")

However, the icon doesn't change and I am instead given this error in the console:

Error Domain=NSCocoaErrorDomain Code=3072 "The operation was cancelled."

How can I fix this issue?

I was stuck with this error for quite a while and tried all sorts of things but couldn't work out what I was doing wrong. I was changing the icon from AppDelegate.application(didFinishLaunchingWithOptions:). Delaying the call with a timer as suggested above did solve it.

It is worth noting that this problem is due to UIKit trying to show a UIAlertController with the message

You have changed the icon for $(PRODUCT_NAME)

and that didn't seem to work at that point. You need to wait until a root view controller is loaded.

This is because this API is not meant to for the developer to update the icon arbitrarily, but for the user to deliberately choose one.