Question

当在类之外使用类型为NSMutableDictionary的属性时，我无法添加对象。

这是class.h文件

@interface cSummary : NSObject 
{
@public
    NSMutableDictionary*    PaymentMethodSalesTotals;
}

@property (nonatomic, retain) NSMutableDictionary*  PaymentMethodSalesTotals;

@end

class.m文件就像这样

    #import "cSummary.h"


@implementation cSummary

@synthesize PaymentMethodSalesTotals;

#pragma mark -
#pragma mark Initialisation

-(id)init
{
    return [super init];

    PaymentMethodSalesTotals = [[ NSMutableDictionary alloc] init];

    [PaymentMethodSalesTotals setObject:[NSNumber numberWithFloat:0.0f] forKey:[NSNumber numberWithInt:10]];
    [PaymentMethodSalesTotals setObject:[NSNumber numberWithFloat:0.0f] forKey:[NSNumber numberWithInt:20]];
    [PaymentMethodSalesTotals setObject:[NSNumber numberWithFloat:0.0f] forKey:[NSNumber numberWithInt:30]];
}

#pragma mark -
#pragma mark Memory management

- (void)dealloc 
{
    if (PaymentMethodSalesTotals != nil)
        [PaymentMethodSalesTotals release];

    [super dealloc];
}


@end

然后在另一个类中使用它

cSummary* oSummary = [[cSummary alloc] init];

NSNumber* numPrice = [NSNumber numberWithFloat:150.0f];
[oSummary.PaymentMethodSalesTotals setObject:numPrice forKey:[NSNumber numberWithInt:10]];

如果我在调试中查看这个，那么PaymentMethodSalesTotals集合中仍然没有值？

Answer 1

在init中，您首先返回，以便不分配/实例化字典。将返回值移动到方法的末尾。

-(id)init
{
    return [super init]; //!!!!!!!!!!!!

    PaymentMethodSalesTotals = [[ NSMutableDictionary alloc] init];
....
}

iPhone SDk：无法将项目添加到用作类属性的NSMutableDictionary中？

1 个答案: