Cannot seem to setEnabled:NO on NSMenuItem

问题:

I have subclassed NSMenu and connected a bunch of NSMenuItem's via Interface Builder. I have tested via the debugger to see that they really get initialized.

The menu is set to not auto enable items. Still when I set any of my NSMenuItem's to [myMenuItem setEnabled:NO] they continue to be enabled. Even if I call [self update] from within the NSMenu subclass.

What am I missing?

回答1:

Had the same issue, so I thought I'd post my solution. NSMenu auto enables NSMenuButtons, so we have to override that.

In IB:

Or programmatically:

// Disable auto enable
[myMenu setAutoenablesItems:NO];

// Test it
[myMenuButton setEnabled:NO];
[myMenuButton setEnabled:YES];

回答2:

I solved it with the help of a colleague, so I post it here for others that experience the same issue.

You should set your NSMenu-sublass to auto-enable items (default behaviour) and then implement this method in the NSMenu-sublass.

- (BOOL)validateMenuItem:(NSMenuItem *)menuItem {
    return [menuItem isEnabled];
}

回答3:

You should uncheck Auto Enables Items on the closest parent NSMenu

回答4:

Adding to the response of itsdavyh, if the menu item is located inside one or more submenus you only have to uncheck the 'Auto enables items'-property on the submenu of the menu item and not on any other parentmenus.

回答5:

You can solve this problem without subclassing.

If only you need is standard menu + some custom NSMenuItems that can be disabled on your control, than you can just:

1. Add one more menu node - just drag and drop Submenu Menu Item from Object library to your menu.

2. Add all NSMenuItems you want to manage to this new Menu node.

3. Open Attributes inspector for your New Menu node, and switch off Auto Enables Items option:

   

4. configure any other options of your menu & items.

Now you can write a code like:

@property (weak) IBOutlet NSMenuItem *hidePlateMenuItem;
...
[self.hidePlateMenuItem setEnabled:NO];

and it will works well.

回答6:

Swift 3 answer:

I have a submenu item under the standard "View" menu called "Enable System Setup On Launch". I use the function below to enable or disable the menu item. Note: the view menu does need the "Auto Enable Items" in IB to be turned off.

func enableSystemSetupMenuItem(enabled:Bool) {
    //set view menu item to enabled: value
    //requires "Auto Enable Items" of "View" menu item to be turned off in IB
    //because "View" menu is now turned off for "Auto Enable" we have to handle all 
    //of the "View" menu items ourselves
    //just to avoid operating on menu separators I set all other menu items to TAG = -1
    let main = NSApplication.shared().menu?.item(withTitle: "View")
    let subMenuItems = main?.submenu?.items
    for item in subMenuItems! {
        if item.title == "Enable System Setup On Launch" {
            item.isEnabled = enabled
        } else if item.tag == -1 {
            item.isEnabled = true
        }
    }
}

回答7:

Try calling [myMenuItem setEnabled:NO] from a different place and making sure that it happens after the menu-containing nib is loaded. Maybe do it right in the subclassed NSMenu's awakeFromNib.

回答8:

I tried all these solution but finally i found the real problem that also make more sense to me. It also is the simplest way to handle disabled nsmenuitem that no needs to subclass or do code. The nsmenuitem before to be child of menu itself is child of the main item for example "Save as..." is child of "File". Just select the parent item (in this example is File) and set off "auto enable menu items" in the menu ispector panel, and here you go!