Send NSArray Via AirDrop

问题

I have an NSMutableArray self.certificates

This array is made up of saved strings and core data. I want to send this through AirDrop. I have checked out serialization and and im trying to send it with the folowing

- (void)send{

NSData *jsonData2 = [NSJSONSerialization dataWithJSONObject:self.certificates options:NSJSONWritingPrettyPrinted error:nil];

NSString *jsonString = [[NSString alloc] initWithData:jsonData2 encoding:NSUTF8StringEncoding];
NSLog(@"Electrical Certificates List:\n%@", jsonString);


UIActivityViewController *activityCtr = [[UIActivityViewController alloc] initWithActivityItems:@[jsonString]
                                                                          applicationActivities:nil];

NSMutableArray *excludedActivities = [self iOSActivities].mutableCopy;
[excludedActivities addObject:UIActivityTypeAddToReadingList];
[excludedActivities addObject:UIActivityTypePostToFlickr];
[excludedActivities addObject:UIActivityTypePostToTencentWeibo];
[excludedActivities addObject:UIActivityTypePostToVimeo];
[activityCtr setExcludedActivityTypes:excludedActivities];

[self presentViewController:activityCtr
                   animated:YES
                 completion:nil];
}

This gives me the following error
'NSInvalidArgumentException', reason: 'Invalid type in JSON write (Certificate)'

I have converted to data to a string so not sure what im missing here

Ive researched NSInvalidArgumentException, reason: 'Invalid type in JSON write (__NSDate)' and How to send NSArray to web service

回答1:

The exception is thrown by JSONSerialization, before the array is converted to data.

To share a custom data type, you'll want to implement NSCoding and UIActivityItemSource on your model object:

@interface CertificateGroup : NSObject <NSCoding, UIActivityItemSource>

@property(copy, nonatomic) NSArray *certificates;

@end

@implementation CertificateGroup

- (void)encodeWithCoder:(NSCoder *)aCoder {
    // Save all your custom properties
    [aCoder encodeObject:self.certificates forKey:@"certificates"]l
}

- (id)initWithCoder:(NSCoder *)aDecoder {
    self = [super init];
    if (self) {
        // Read back properties
        self.certificates = [aDecoder decodeObjectForKey:@"certificates"];
    }
    return self;
}

- (id)activityViewControllerPlaceholderItem:(UIActivityViewController *)activityViewController
{
    //Let the activity view controller know NSData is being sent by passing this placeholder.
    return [NSData data];
}

- (id)activityViewController:(UIActivityViewController *)activityViewController itemForActivityType:(NSString *)activityType
{
    //Serialize this object for sending. NSCoding protocol must be implemented for the serialization to occur.
    return [NSKeyedArchiver archivedDataWithRootObject:self];
}

- (NSString *)activityViewController:(UIActivityViewController *)activityViewController dataTypeIdentifierForActivityType:(NSString *)activityType {
    return @"com.mycompany.myapp.certificates";
}

@end

Then, when you create your activity view controller:

CertificatesGroup *group = [CertificatesGroup new];
group.certificates = self.certificates;
UIActivityViewController *activityCtr = [[UIActivityViewController alloc] initWithActivityItems:@[group]
                                                                          applicationActivities:nil];
...

You're app delegate should implement -application:openURL:sourceApplication:annotation: and decode the incoming certificates.

- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation {
     NSData *groupData = [NSData dataWithContentsOfURL:url];
     CertificatesGroup *group = [NSKeyedUnarchiver unarchiveObjectWithData:groupData];
     NSLog(@"%@", group.certificates);
     return YES;
}

For more info, see Apple's AirDropSample project, especially APLProfile.h/.m, APLProfileViewController.h/.m and AppDelegate.m.

来源：https://stackoverflow.com/questions/22769911/send-nsarray-via-airdrop

标签

ios

objective-c

cocoa-touch

serialization

airdrop