单击菜单项时无回调 [英] No callback when clicking menu item

问题描述

我正在尝试在FinderSync扩展中实现一个简单的上下文菜单.

I'm trying to implement a simple context menu in my FinderSync extension.

我使用一些示例构建了以下内容，但我的问题是，单击菜单项时从未调用过回调.

I built the following using some examples, and my problem is that the callback is never called when I click the menu item.

源代码:

ContextMenuHelper.h

#import <Foundation/Foundation.h>
#include "FinderSync.h"

@interface ContextMenuHelper : NSObject

+ (NSMenu *)buildMenu;

@end

ContextMenuHelper.m

#import "ContextMenuHelper.h"

#define SharedContextMenuTarget  [ContextMenuTarget sharedInstance]

@interface ContextMenuTarget : NSObject
+ (ContextMenuTarget *) sharedInstance;
@end

@implementation ContextMenuTarget

- (void) callback              : (id)sender {
    NSLog(@"Called back!!!");
}

+ (ContextMenuTarget *) sharedInstance
{
    static ContextMenuTarget *sharedContextMenuTarget = nil;
    @synchronized(self)
    {
        if (!sharedContextMenuTarget)
            sharedContextMenuTarget = [[ContextMenuTarget alloc] init];
        return sharedContextMenuTarget;
    }
}

@end

@implementation ContextMenuHelper

+ (NSMenu *)buildMenu
{
    ContextMenuTarget *contextMenuTarget = SharedContextMenuTarget;

    NSMenu *mySubmenu = [[NSMenu alloc] initWithTitle:@""];

    NSMenuItem *newMenu = [[NSMenuItem alloc] initWithTitle:@"hello"
                                                     action:@selector(callback:)
                                              keyEquivalent:@""];
    [newMenu setTarget:contextMenuTarget];
    [mySubmenu addItem:newMenu];

    return mySubmenu;
}

@end

MyFinderSync.m

...
- (NSMenu *)menuForMenuKind:(FIMenuKind)whichMenu {

    NSMenu *myContextMenu = [[NSMenu alloc] initWithTitle:@""];

    @try
    {
        if(whichMenu != FIMenuKindContextualMenuForItems) {
            return myContextMenu;
        }

        myContextMenu = [ContextMenuHelper buildMenu];
    }
    @catch (NSException *ex)
    {
    }

    return myContextMenu;
}
...

推荐答案

显然，仅当目标是FinderSync的实例时，回调才有效.找不到支持该理论的任何文档，但是解决该问题的唯一方法是将上下文菜单代码移至 MyFinderSync.m :

Apparently, callbacks will only work if the target is the instance of FinderSync. Could not find any documentation to support this theory, but the only thing that fixed the problem was moving the context menu code into MyFinderSync.m:

...
- (NSMenu *)menuForMenuKind:(FIMenuKind)whichMenu {

    NSMenu *myContextMenu = [[NSMenu alloc] initWithTitle:@""];

    @try
    {
        if(whichMenu != FIMenuKindContextualMenuForItems) {
            return myContextMenu;
        }

        myContextMenu = [self buildMenu];
    }
    @catch (NSException *ex)
    {
    }

    return myContextMenu;
}

- (NSMenu *)buildMenu
{
    NSMenu *mySubmenu = [[NSMenu alloc] initWithTitle:@""];

    NSMenuItem *newMenu = [[NSMenuItem alloc] initWithTitle:@"hello"
                                                     action:@selector(callback:)
                                              keyEquivalent:@""];
    [newMenu setTarget:self];
    [mySubmenu addItem:newMenu];

    return mySubmenu;
}

- (void) callback              : (id)sender {
    NSLog(@"Called back!!!");
}
...

这篇关于单击菜单项时无回调的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！