objective-c - 为什么 Xcode 给出这些错误？

Question

我得到的错误是 Xcode 说 3 件事未声明(见下图) alt text http://snapplr.com/snap/ks4h

但是在头文件中我已经声明了它们(见下图)

alt text http://snapplr.com/snap/htmb

为什么当我声明这些错误时我会收到这些错误。

完整代码:

头文件。

#import <Foundation/Foundation.h>


@interface HotKeyController : NSObject {
    IBOutlet NSButton *cmdHK;
    IBOutlet NSButton *ctrHK;
    IBOutlet NSButton *optHK;
    IBOutlet NSPopUpButton *keyHK;
    IBOutlet NSWindow *window;
    IBOutlet NSWindow *searchWindow;
    IBOutlet NSWindow *entryWindow;
}

@end

实现文件

#import "HotKeyController.h"
#include <Carbon/Carbon.h>

@implementation HotKeyController

OSStatus MyHotKeyHandler(EventHandlerCallRef nextHandler,EventRef theEvent,void *userData)
{
    EventHotKeyID hkCom;
    GetEventParameter(theEvent,kEventParamDirectObject,typeEventHotKeyID,NULL,sizeof(hkCom),NULL,&hkCom);
    int l = hkCom.id;

    switch (l) {
        case 1: [window makeKeyAndOrderFront:NSApp];  
            break;
        case 2: [searchWindow makeKeyAndOrderFront:nil];
            break;
        case 3: [entryWindow makeKeyAndOrderFront:nil];
            break;  
    }
    return noErr;
}

- (void)awakeFromNib
{
    //Register the Hotkeys
    EventHotKeyRef gMyHotKeyRef;
    EventHotKeyID gMyHotKeyID;
    EventTypeSpec eventType;
    eventType.eventClass=kEventClassKeyboard;
    eventType.eventKind=kEventHotKeyPressed;


    InstallApplicationEventHandler(&MyHotKeyHandler,1,&eventType,pl,NULL);

    gMyHotKeyID.signature='htk1';
    gMyHotKeyID.id=1;
    if([[NSUserDefaults standardUserDefaults] integerForKey:@"hotkeyShowMain"]!=-999) {
        RegisterEventHotKey([[NSUserDefaults standardUserDefaults] integerForKey:@"hotkeyShowMain"], [[NSUserDefaults standardUserDefaults] integerForKey:@"hotkeyShowMainModifier"], gMyHotKeyID, GetApplicationEventTarget(), 0, &gMyHotKeyRef);
    }

    gMyHotKeyID.signature='htk2';
    gMyHotKeyID.id=2;
    if([[NSUserDefaults standardUserDefaults] integerForKey:@"hotkeyShowSearch"]!=-999) {
        RegisterEventHotKey([[NSUserDefaults standardUserDefaults] integerForKey:@"hotkeyShowSearch"], [[NSUserDefaults standardUserDefaults] integerForKey:@"hotkeyShowSearchModifier"], gMyHotKeyID, GetApplicationEventTarget(), 0, &gMyHotKeyRef);
    }

    gMyHotKeyID.signature='htk3';
    gMyHotKeyID.id=3;
    if([[NSUserDefaults standardUserDefaults] integerForKey:@"hotkeyShowEntry"]!=-999) {
        RegisterEventHotKey([[NSUserDefaults standardUserDefaults] integerForKey:@"hotkeyShowEntry"], [[NSUserDefaults standardUserDefaults] integerForKey:@"hotkeyShowEntryModifiers"], gMyHotKeyID, GetApplicationEventTarget(), 0, &gMyHotKeyRef);
    }

}

@end

Answer 1

The error I get is Xcode saying 3 things are un-declared …

But in the Header File I have declared them …

Why I am getting these errors when I have declared them [in the HotKeyController class].

因为这些行位于函数中，而不是 HotKeyController 类的方法中。将函数放在哪里(是否在 @implementation 内)并不重要；它仍然是一个函数，而不是一个方法。

How would I make the userData parameter point to my HotKeyController?

您可以在创建事件处理程序时进行设置。事实上，您已经将其设置为“pl”，无论它是什么。