Question

我尝试编写rhodes本机扩展扩展来打开 iOS MailComposer 。现在代码“工作”，但 MFMailComposeViewController 没有显示，xcode显示警告：

Attempt to present <MFMailComposeViewController: 0x12b60840> on <Iosmailto: 0xc1898d0> whose view is not in the window hierarchy!

我读到UIViewControllers必须在层次结构中，但我不能从Rhodes ruby代码或clear-C扩展包装器中提供。现在我正在尝试使用 [UIApplication sharedApplication] .keyWindow.rootViewController 中的 MFMailComposeController 来呈现我的 UIViewController ，但邮件编辑器尚未显示。

来自iosmailto.h的

接口：

@interface Iosmailto : UIViewController<MFMailComposeViewControllerDelegate>
{
}
    @property(nonatomic, assign) id delegate;
    //-(IBAction)send_mail:(id)sender;
@end

从iosmailto.m实施：

@implementation Iosmailto

    - (void)viewDidLoad {
        [super viewDidLoad];
        [self send_mail];
    }

    - (void)send_mail {
        if ([MFMailComposeViewController canSendMail]) {

            MFMailComposeViewController *composer = [[MFMailComposeViewController alloc] init];
            composer.mailComposeDelegate = self;
            [composer setSubject:[NSString stringWithUTF8String:subj]];

            NSArray *recipients_array = [NSArray arrayWithObject:[NSString stringWithUTF8String:recipients]];

            [composer setToRecipients:recipients_array];

            NSString *composerBody = [NSString stringWithUTF8String:message];
            [composer setMessageBody:composerBody isHTML:NO];

            [composer setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
            [self presentModalViewController:composer animated:YES];

            [composer release];
        } else {

            NSLog(@"Device is unable to send email in its current state.");
        }
    }
    /* some unnecessary for this question methods */

@end

在iosmailto.m中定义的C函数是从Rhodes调用的：

// find root vc
UIViewController *topController = [UIApplication sharedApplication].keyWindow.rootViewController;

// find topmost vc
while (topController.presentedViewController) {
    topController = topController.presentedViewController;
}

iosmailer = [[Iosmailto alloc] init];

iosmailer.delegate = topController;
[topController presentViewController:iosmailer animated:YES completion:nil];

此应用不适用于AppStore。如果需要，欢迎黑客。

Iosmailto的

更新初始化：

- (id)init
{
   self = [super initWithNibName:nil bundle:nil];
   return self;
}

更新2 此代码的简短版本（没有UIViewController包装器）是我的出发点。那也行不通。这有相同的警告，还有一个警告：

UIViewController *topController = [UIApplication sharedApplication].keyWindow.rootViewController;

while (topController.presentedViewController) {
    topController = topController.presentedViewController;
}
if ([MFMailComposeViewController canSendMail]) {
    MFMailComposeViewController *composer = [[MFMailComposeViewController alloc] init];
    composer.mailComposeDelegate = (id<MFMailComposeViewControllerDelegate>)topController ;

    [composer setSubject:[NSString stringWithUTF8String:subj]];
    NSArray *recipients_array = [NSArray arrayWithObject:[NSString stringWithUTF8String:recipients]];
    [composer setToRecipients:recipients_array];
    NSString *composerBody = [NSString stringWithUTF8String:message];
    [composer setMessageBody:composerBody isHTML:NO];
    [composer setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
    [topController presentModalViewController:composer animated:YES];

    [composer release];
} else {
}

Answer 1

使用此代码呈现视图控制器

[[[[[UIApplication sharedApplication] delegate] window] rootViewController] presentViewController:composer
                                                                                                     animated:YES
                                                                                                   completion:nil];

Answer 2

好的我认为问题是你的UIViewController在它的view属性中没有任何东西，因为你没有使用.xib文件来初始化它。 See this question以编程方式创建UIView并将其分配给UIViewController的view属性。我认为这是正确的方法。查看他们的-(void)loadView方法的实现。

您的用例也有点奇怪，因为看起来您的Iosmailto UIViewController没有任何内容，并且您只是将它用作MFMailComposeViewController的包装器 - 您可以考虑直接重新实现您的C方法创建一个MFMailComposeViewController，没有不必要的UIViewController的间接层，这个UIViewController本身不会显示任何内容。

Ios MFMailComposeViewController不显示

2 个答案: