Custom dock icon reverts to old one whenever the app is open.

Gaffer74 wrote:

They didn’t give us the option in 2002 and then just “forget about it”. The fact  that multiple OS’s have always allowed it, coupled to the fact that they still provide user up to date guides on how to do it:

Change icons for files or folders on Mac – Apple Support (UK)

means that Apple still allow and encourage end users to change the icon today in 2023.

…I have changed the icon as they suggested and this is happening to 2 apps

Why not? The people who added the ability to change an icon have long since retired. All new development on the Mac is focused on porting features from the iPhone. The fact that some documentation doesn't work in all cases is irrelevant. Pretty much every Apple support document doesn't work in some cases.

Thanks for the reply (nice to get a devs perspective) but I don’t buy that explanation.

Unless of course there is a valid reason for a developer to:

Completely allow icon change on the desktop

Completely allow icon change in Launchpad

Allow icon change in the dock as well

Then want the dock icon alone to magically change back to the old one whilst the app is running

During this time the dock icon is static and has NO dynamic features at all (eg no stats being shown in the icon)

….But then when you close the app the dock allows the icon to change back again

That dev also ONLY wants this to happen on the dock - in Launchpad and finder and everywhere else, the icon remains as you changed it.

I’m sorry but I’m not convinced the above scenario is plausible or even desired.

You have described the current Dock Tile Icon API with 100% accuracy. That is precisely the way it works, more or less. It is the operating system that allows the user to change the static app icon. But then the operating system also allows the developer to dynamically update the icon in the Dock while the app is running. The developer doesn't have to display any dynamic features. It could be something simple, as in my case, where I want the start round icon to display square to match the square icon theme of a newer operating system. I can also use it to show animation like a progress bar. VLC can use it to add a Santa cap to their icon.

There is a new API from the iPhone that hasn't yet been ported to macOS that would allow a developer to change the static icon on the Desktop and LaunchPad. However, the choices are limited. And it would conflict with the current free rein given to the user on the Mac. Eventually, you will probably lose that capability to change icons.

I am leaning towards the idea that since a recent Ventura update, the dock possibly is handling the icons slightly differently and rather than reading from the app itself is getting the image from a cache somewhere?

Yes. That's what I keep telling you. That's how it works. The app can change that.

Of course it wouldn’t explain why it’s only happened to 2 apps (and 1 of those apps only in the past month) but I don’t think it’s a developer stipulation, more a recent odd behaviour of the dock in Ventura - just wanted to find out why.

Why do you refuse to accept my explanation for it? That's literally the way it works. Most apps don't change their Dock Tile. I just checked my own app and it seems to work with a custom icon. I was a bit surprised by this because my app has been heavily pirated and I make sure to check the signature. Apple's signature checking does seem to allow a custom app icon. But then when my app displays its own icon in a window, it shows the custom icon. The custom Dock Tile is current, however. So that definitively proves my explanation that you reject.

I'll have to make some changes in code now. I don't want to ever display a custom icon. In one case, pirates actually used that custom icon functionality. So thanks for your post. I hadn't thought about people using this obscure feature. I'll put a stop to it. 😄

leroydouglas wrote:

I don't understand the fascination with changing icons.

it's the same reasons why people customize cars, harleys etc...

it's fun.

it looks nice for some of us.

and it kind of makes your Mac uniquely yours.

:)

Gaffer74 wrote:

I have changed the app icon for 2 apps (VLC and JustColourPicker) and it shows the new icon in the dock only when the app is not open.

However, as soon as I launch that app, the old icon reappears in the dock. When I close the app, the new icon appears again. I have tried replacing the favicon.icns file in the package contents but it still happens (not sure where it's getting the old image from if I've now removed it). I've also restarted the Dock and Finder several times.

Nothing seems to work, the custom icons only appear when NOT using that app, when you use it the old icon reappears.

Can anyone help?

(BTW It always shows the new icon correctly in Finder and Launchpad whether app launched or not - it's only the dock that exhibits this behaviour)

You can try Control clicking on the App icon in the /Application Folder>Show Package Contents here you can inspect Resources, and see if this get s you any further.

Gaffer74 wrote:

Yep, already done that as mentioned because that's where I changed the .icns file for the app (inside the resources folder). Some apps I have name this AppIcon.icns, others favicons.icns, others generic.icns...etc

This is why I don't understand the icon reverting - by changing the ***.icns file within the app itself, where is the dock getting the old image from?

I don't understand the fascination with changing icons.

Typically files and folder and app Command i opens the Get Info pane on your selection highlight the upper left associated image, then from here opening your image, Command A to select all, then copy & paste is the procedure ...

Not via the Content Package.

if it does not work it does not work.

file types .icns are typically not one image but multiple files, that scale..

Favicons are tiny 16x16 pixel for use on the browser tabs and bookmarks bar.

Generic is a simple catch all file name like AppIcon—no mystery there.

Gaffer74 wrote:

“It's 2023. You just can't do these kinds of hacks anymore.”

Fair point but this isn’t really a hack imho, Apple have always allowed you to openly change an icon since the beginning of OSX

To “allow” something in 2002 and then ensure that it continues to work the same way in 2023 are two completely different things.

Apple recently made a change in iOS that allows app developers to support custom icons. The most likely explanation is that Apple is porting this feature to the Mac. In the process, they may broken one or both of the previous customization methods on the Mac. This is an obscure, advanced feature that you should expect to be unreliable. If an app wants to set its own icon, should that functionality break is the user has changed the icon?

For example, my own app supports many different versions of the OS. It has a round icon that gets displayed as square when run on a modern system. Plus, it draws a progress bar while running. I wouldn’t want the user to override that behaviour.

Apps can set their own icons when they run. You can't override that.

VLC has used a custom, dynamic icon for years. Just pay a movie anytime around Christmas.

It's 2023. You just can't do these kinds of hacks anymore.