Refresh icons for files or folders in finder using cocoa - cocoa

Question

I'm developing a cocoa application for Mac. I'm applying overlay icons on files and folders using my application. But my problem is that when I change icon for file or folder from my Application than its not reflecting it in the Finder unless I click on any file or folder in the Finder. For refreshing Finder I'm running following applescript using following code from my Application:
NSString *source=[NSString stringWithFormat:#"tell application \"Finder\" to update POSIX file \"%#\"",itemPath];
NSAppleScript *run = [[NSAppleScript alloc] initWithSource:source];
[run executeAndReturnError:nil];
But this code is not refreshing my Finder. Any idea how to refresh Finder to immediately reflect icon for file or folder??? Thanks in advance...

Answer 1

You must specify the class (folder, file, disk, item, ...) when you use a string in the Finder, item will work for all (folder, file, ...).
Without it, It works for some, but it is not the case for everyone
Also, "posix file thePath" in the Finder is more reliable with parentheses.
Try this
NSString *source=[NSString stringWithFormat:#"tell application \"Finder\" to update item (POSIX file \"%#\")",itemPath];
Or without NSApplescript :
[[NSWorkspace sharedWorkspace] noteFileSystemChanged: itemPath];

Answer 2

#"tell application \"Finder\" to update POSIX file \"%#\"" this script working fine for me.
You can also use apple events.
Below code is written by JWWalker
OSStatus SendFinderSyncEvent( const FSRef* inObjectRef )
{
AppleEvent theEvent = { typeNull, NULL };
AppleEvent replyEvent = { typeNull, NULL };
AliasHandle itemAlias = NULL;
const OSType kFinderSig = 'MACS';
OSStatus err = FSNewAliasMinimal( inObjectRef, &itemAlias );
if (err == noErr)
{
err = AEBuildAppleEvent( kAEFinderSuite, kAESync, typeApplSignature,
&kFinderSig, sizeof(OSType), kAutoGenerateReturnID,
kAnyTransactionID, &theEvent, NULL, "'----':alis(##)", itemAlias );
if (err == noErr)
{
err = AESendMessage( &theEvent, &replyEvent, kAENoReply,
kAEDefaultTimeout );
AEDisposeDesc( &replyEvent );
AEDisposeDesc( &theEvent );
}
DisposeHandle( (Handle)itemAlias );
}
return err;
}

Answer 3

Here's how I "refresh the Finder" when needed. Maybe it will help you ;)
tell application "Finder"
tell window 1 to update items
end tell

Answer 4

What worked for me is to 'touch' the file which updates the file modification date and thus triggers thumbnail icon refresh by the Finder.
NSString* path = "/Users/xx/...path_to_file"
NSString* command = [NSString stringWithFormat:#"touch \"%#\"", path];
int res = system(command.UTF8String);