無法從對象創建BOOL

Question

我正在按照mac os x第4版的指導cocoa編程。在第32章中，我弄糟了代碼，而且我沒有對它進行備份，所以我不得不從下載大的解決方案書呆子牧場。
該項目是關於核心數據關係的，有一個Employee類和一個Class類。

Employee.h：

#import <Foundation/Foundation.h> 
#import <CoreData/CoreData.h> 

@class Department; 

@interface Employee : NSManagedObject 

@property (nonatomic, copy) NSString * firstName; 
@property (nonatomic, copy) NSString * lastName; 
@property (nonatomic, retain) Department *department; 
@property (nonatomic, readonly) NSString *fullName; 

@end 

Employee.m：

#import "Employee.h" 
#import "Department.h" 


@implementation Employee 

@dynamic firstName; 
@dynamic lastName; 
@dynamic department; 

+ (NSSet *)keyPathsForValuesAffectingFullName 
{ 
    return [NSSet setWithObjects:@"firstName", @"lastName", nil]; 
} 

- (NSString *)fullName 
{ 
    NSString *first = [self firstName]; 
    NSString *last = [self lastName]; 
    if (!first) 
     return last; 
    if (!last) 
     return first; 
    return [NSString stringWithFormat:@"%@ %@", first, last]; 
} 

@end 

Department.h：

#import <Foundation/Foundation.h> 
#import <CoreData/CoreData.h> 


@interface Department : NSManagedObject 

@property (nonatomic, retain) NSString * deptName; 
@property (nonatomic, retain) NSSet *employees; 
@property (nonatomic, retain) NSManagedObject *manager; 
@end 

@interface Department (CoreDataGeneratedAccessors) 

- (void)addEmployeesObject:(NSManagedObject *)value; 
- (void)removeEmployeesObject:(NSManagedObject *)value; 
- (void)addEmployees:(NSSet *)values; 
- (void)removeEmployees:(NSSet *)values; 

@end 

Department.m：

#import "Department.h" 
#import "Employee.h" 

@implementation Department 

@dynamic deptName; 
@dynamic employees; 
@dynamic manager; 

- (void)addEmployeesObject:(Employee *)value 
{ 
    NSLog(@"Dept %@ adding employee %@", 
      [self deptName], [value fullName]); 
    NSSet *s = [NSSet setWithObject:value]; 
    [self willChangeValueForKey:@"employees" 
       withSetMutation:NSKeyValueUnionSetMutation 
        usingObjects:s]; 
    [[self primitiveValueForKey:@"employees"] addObject:value]; 
    [self didChangeValueForKey:@"employees" 
       withSetMutation:NSKeyValueUnionSetMutation 
        usingObjects:s]; 
} 

- (void)removeEmployeesObject:(Employee *)value 
{ 
    NSLog(@"Dept %@ removing employee %@", 
      [self deptName], [value fullName]); 
    Employee *manager = (Employee *)[self manager]; 
    if (manager == value) { 
     [self setManager:nil]; 
    } 
    NSSet *s = [NSSet setWithObject:value]; 
    [self willChangeValueForKey:@"employees" 
       withSetMutation:NSKeyValueMinusSetMutation 
        usingObjects:s]; 
    [[self primitiveValueForKey:@"employees"] removeObject:value]; 
    [self didChangeValueForKey:@"employees" 
       withSetMutation:NSKeyValueMinusSetMutation 
        usingObjects:s]; 
} 


@end 

我有這些核心數據relashionships和實體：

我也使用一些陣列控制器到核心數據值綁定到一些出口。
完整的項目可以在「下載解決方案」中找到here。，第32章（與我的相同）。 告訴我，如果你需要更多的代碼來理解這個錯誤：

2012-10-31 15:27:43.977 Departments[1229:303] Cannot create BOOL from object (
) of class _NSControllerArrayProxy 
2012-10-31 15:27:43.989 Departments[1229:303] Cannot create BOOL from object (
) of class _NSControllerArrayProxy 

好像張貼整個項目是不推薦，但我可以這樣做，如果你說這是好的。 PS：我使用從解決方案下載的代碼，它是一樣的，但它不起作用，也許是因爲我有更高版本的xcode。

Answer 1

看起來像一個綁定問題。你可能有一個「啓用」或「隱藏」的綁定（需要一個BOOL）與一個無法轉換爲BOOL的屬性鏈接。