MFMailComposeViewController：取消按钮不可见

Question

我遇到了这个问题。如果我点击取消按钮的地方我得到模态。但我无法看到取消按钮。我认为这是因为标题颜色。但我不确定。请查看附带的屏幕截图。我附上了代码。

#import "SupportControllerViewController.h"
#import <MessageUI/MFMailComposeViewController.h>

@interface SupportControllerViewController ()

@end

@implementation SupportControllerViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    UITapGestureRecognizer *mailUsTab = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(mailUs)];
    mailUsTab.numberOfTapsRequired=1;
    mailUsTab.delegate=self;
    [self.rightView addGestureRecognizer:mailUsTab];
}

- (IBAction)backBtn:(id)sender {
    [self.navigationController dismissViewControllerAnimated:YES completion:^{
    }];
}

- (void)mailUs {
    if (![MFMailComposeViewController canSendMail]) {
        NSLog(@"Mail services are not available.Please check your mail app.");
        return;
    }
    {
    MFMailComposeViewController *mailcontroller = [[MFMailComposeViewController alloc] init];
    mailcontroller.mailComposeDelegate = self;
    //mailcontroller.delegate = self;
    [self presentViewController:mailcontroller animated:YES completion:nil];
    }
}

- (void)mailComposeController:(MFMailComposeViewController*)controller
      didFinishWithResult:(MFMailComposeResult)result
                    error:(NSError*)error;
{
    NSLog(@"Coming here");
    if (result == MFMailComposeResultSent) {
        [self.view makeToast:@"We have received your mail.We will contact you as soon as possible"
                duration:3.0
                position:CSToastPositionCenter];
    }

    if (result == MFMailComposeResultFailed) {
         [self.view makeToast:@"Some error has occurred.Please check your internet connection."
                duration:3.0
                position:CSToastPositionCenter];
    }
    if(result == MFMailComposeResultCancelled){
    }
    if(result == MFMailComposeResultSaved){
    }
    [controller dismissViewControllerAnimated:YES completion:nil];
    return;
}

@end

Answer 1

    [[UIBarButtonItem appearance] setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:
                                                      [UIColor whiteColor],NSForegroundColorAttributeName, nil] forState:UIControlStateNormal];
    [[UIBarButtonItem appearance] setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:
                                                      [UIColor whiteColor],NSForegroundColorAttributeName, nil] forState:UIControlStateHighlighted];

我更改了TitleTextAttributes颜色。现在它奏效了。

Answer 2

请尝试使用以下代码，而不是

[self presentViewController:mailcontroller animated:YES completion:nil];

试试这个，

[self presentViewController:mailcontroller animated:YES completion:^{
        [[UIBarButtonItem appearance] setTintColor:[UIColor whiteColor]]; // Choose color as per your preference.
        [[UINavigationBar appearance] setBarTintColor:[UIColor whiteColor]];
    }];