使数组控制器成为按钮的目标

Question

我正在COCOA PROGRAMMING FOR MAC OS X (3RD EDITION)上NSArrayController的一章工作，它告诉我：

Control-Drag使阵列控制器成为Add New Employee按钮的目标。设置要添加的操作：

然而，当我拖过array controller时，它没有突出显示，因此我没有选择目标选项。

如何在新的XCode

中正确执行此操作

full size image

document.h：

//
//  Document.h
//  RaiseMan
//
//  Created by user on 11/12/11.
//  Copyright (c) 2011 __MyCompanyName__. All rights reserved.
//

#import <Cocoa/Cocoa.h>

@interface Document : NSDocument
{
    NSMutableArray *employees;
}

@end

document.m：

//
//  Document.m
//  RaiseMan
//
//  Created by user on 11/12/11.
//  Copyright (c) 2011 __MyCompanyName__. All rights reserved.
//

#import "Document.h"

@implementation Document

- (id)init
{
    self = [super init];
    if (self) {
        employees = [[NSMutableArray alloc] init];
    }
    return self;
}

- (void)dealloc
{
    [self setEmployees:nil];
    [super dealloc];
}


-(void)setEmployees:(NSMutableArray *)a
{
    //this is an unusual setter method we are goign to ad a lot of smarts in the next chapter
    if (a == employees)
        return;
    [a retain];
    [employees release];
    employees = a;
}

- (NSString *)windowNibName
{
    // Override returning the nib file name of the document
    // If you need to use a subclass of NSWindowController or if your document supports multiple NSWindowControllers, you should remove this method and override -makeWindowControllers instead.
    return @"Document";
}

- (void)windowControllerDidLoadNib:(NSWindowController *)aController
{
    [super windowControllerDidLoadNib:aController];
    // Add any code here that needs to be executed once the windowController has loaded the document's window.
}

- (NSData *)dataOfType:(NSString *)typeName error:(NSError **)outError
{
    /*
     Insert code here to write your document to data of the specified type. If outError != NULL, ensure that you create and set an appropriate error when returning nil.
    You can also choose to override -fileWrapperOfType:error:, -writeToURL:ofType:error:, or -writeToURL:ofType:forSaveOperation:originalContentsURL:error: instead.
    */
    NSException *exception = [NSException exceptionWithName:@"UnimplementedMethod" reason:[NSString stringWithFormat:@"%@ is unimplemented", NSStringFromSelector(_cmd)] userInfo:nil];
    @throw exception;
    return nil;
}

- (BOOL)readFromData:(NSData *)data ofType:(NSString *)typeName error:(NSError **)outError
{
    /*
    Insert code here to read your document from the given data of the specified type. If outError != NULL, ensure that you create and set an appropriate error when returning NO.
    You can also choose to override -readFromFileWrapper:ofType:error: or -readFromURL:ofType:error: instead.
    If you override either of these, you should also override -isEntireFileLoaded to return NO if the contents are lazily loaded.
    */
    NSException *exception = [NSException exceptionWithName:@"UnimplementedMethod" reason:[NSString stringWithFormat:@"%@ is unimplemented", NSStringFromSelector(_cmd)] userInfo:nil];
    @throw exception;
    return YES;
}

+ (BOOL)autosavesInPlace
{
    return YES;
}


    - (void)setEmployees:(NSMutableArray *)a;

    @end

person.h：

//
//  Person.h
//  RaiseMan
//
//  Created by user on 11/12/11.
//  Copyright (c) 2011 __MyCompanyName__. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface Person : NSObject
{
    NSString *personName;
    float expectedRaise;
}

@property (readwrite, copy) NSString *personName;
@property (readwrite) float expectedRaise;

@end

person.m：

//
//  Person.m
//  RaiseMan
//
//  Created by user on 11/12/11.
//  Copyright (c) 2011 __MyCompanyName__. All rights reserved.
//

#import "Person.h"

@implementation Person

- (id) init
{
    self = [super init];
    expectedRaise = 5.0;
    personName = @"New Person";
    return self;    
}

- (void)dealloc
{
    [personName release];
    [super dealloc];
}

@synthesize personName;
@synthesize expectedRaise;

@end

Answer 1

老兄..你在IB做错了。这是错的 -

这些条目应在数组控制器的属性检查器中进行 -

纠正后，您将能够正确设置目标：）