NSSharingService 用于发送电子邮件并读取电子邮件正文

我正在使用 NSSharingService 在邮件应用程序中打开一个电子邮件撰写窗口：

NSSharingService* sharingService = [NSSharingService sharingServiceNamed:NSSharingServiceNameComposeEmail];
[sharingService setRecipients:@[@"[email protected] /cdn-cgi/l/email-protection"]];
[sharingService setSubject:@"Test"];
sharingService.delegate = self;

它可以很好地打开撰写电子邮件窗口，当我输入一些文本并实际发送电子邮件时，我什至会收到对委托的回调：

- (void)sharingService:(NSSharingService *)sharingService didShareItems:(NSArray *)items {
    NSLog(@"sharingService didShareItems - %@", sharingService.messageBody);
}

问题是它返回的messageBody总是nil。我期望它包含已发送的电子邮件的文本。我检查了 NSSharingService 的头文件：

/* These read-only properties allow for querying of the shared content:
 */
// Message body as string
@property (readonly, copy) NSString *messageBody NS_AVAILABLE_MAC(10_9);
// URL to access the post on Facebook, Twitter, Sina Weibo, etc. (also known as permalink)
@property (readonly, copy) NSURL *permanentLink NS_AVAILABLE_MAC(10_9);
// Account name used for sending on Twitter or Sina Weibo
@property (readonly, copy) NSString *accountName NS_AVAILABLE_MAC(10_9);
// NSArray of NSURL objects representing the file that were shared
@property (readonly, copy) NSArray *attachmentFileURLs NS_AVAILABLE_MAC(10_9);

知道为什么这可能行不通吗？如果我使用的话似乎工作正常NSSharingServiceNameComposeMessage而不是电子邮件，但那是为了发送 iMessages。

不确定为什么它在您的情况下不起作用，但这应该或多或少是要遵循的标准模式：

@interface sharingServiceDelegate : NSObject <NSSharingServiceDelegate>
@end

@interface sharingServiceDelegate ()
@property NSString *recipientString;
@property NSString *subjectString;
@property NSString *bodyString;
@property NSURL <NSPasteboardWriting> *attachmentURL;
@property NSSharingService *emailSharingService;
@end


@implementation sharingServiceDelegate

- (id)init {

    self = [super init];

    if (self) {
        NSSharingService *emailSharingService = [NSSharingService sharingServiceNamed:NSSharingServiceNameComposeEmail];
        emailSharingService.delegate = self;
        self.emailSharingService = emailSharingService;
    }

    return self;
}

- (BOOL)shareUsingEmail
{
    NSArray *shareItems =@[_bodyString, _attachmentURL];
    self.emailSharingService.recipients = @[_recipientString];
    self.emailSharingService.subject = _subjectString;

    if([self.emailSharingService canPerformWithItems:shareItems]){
        [self.emailSharingService performWithItems:shareItems];
        return TRUE;
    } else {
        // handle failure ...
    }

    return FALSE;
}

@end

然后，您实际上可以在任何需要的地方执行共享服务：

sharingServiceDelegate * shareDelegate = [[sharingServiceDelegate alloc] init];

shareDelegate.recipientString = @"[email protected] /cdn-cgi/l/email-protection";
shareDelegate.subjectString = @"a subject";
shareDelegate.bodyString = @"A message body";
shareDelegate.attachmentURL = [NSURL fileURLWithPath:[NSString stringWithCString:file_to_share_path encoding:NSUTF8StringEncoding]];

if([shareDelegate shareUsingEmail]==FALSE)
    NSLog(@"Email Sharing Service failed.\n");
}