.[NSOpenPanel directoryURL] gives error: No visible @interface for 'NSOpenPanel' declares the selector 'directoryURL:'

Question

I'm using Xcode, building with base SDK and deployment target: OS X 10.8 , trying to use [NSOpenPanel directoryURL] which the offical documentation says is

Available in OS X v10.6 and later

But I get the error:

ARC Semantic issue - No visible @interface for 'NSOpenPanel' declares the selector 'directoryURL:'

Code:

#import <Cocoa/Cocoa.h>
// #import <NSOpenPanel.h> // No good
@import AppKit;

void fileOpen()
{
    NSOpenPanel *openPanel = [NSOpenPanel openPanel];
    // [openPanel setDirectory:@""]; // works, but deprecated in OSX 10.6
    [openPanel directoryURL: [NSURL URLWithString:@"file:///path/"]];
    // ...
} 

So what am I doing wrong here?

Answer 1

directoryURL is a property and does not take a string argument like what you were originally guessing. That's why you were seeing the error when trying to resolve the directoryURL:' selector.

The directoryURL property does have a getter and setter, though.

Try using:

[openPanel setDirectoryURL: [NSURL URLWithString:@"file:///path/"]];

or:

openPanel.directoryURL = [NSURL fileURLWithPath:@"path"];