Question

我的应用程序中有一个按钮，当按下它时，MFMailComposerViewController将显示，当作曲家解散时，带有自定义视图的MBProgressHUD将显示告诉用户邮件是否成功发送。

如果我按下作曲家中的发送按钮，邮件将被发送，作曲家将被解雇并且HUD将显示，它工作正常。但是，如果我在作曲家视图中按下取消按钮，作曲家会解散，但HUD不显示，并且应用程序崩溃。

以下是崩溃日志。

2012-02-02 22:49:34.821 App[5091:707] -[ViewController size]: unrecognized selector 
sent to instance 0x319210
2012-02-02 22:49:34.831 App[5091:707] *** Terminating app due to uncaught exception 
'NSInvalidArgumentException', reason: '-[ViewController size]: unrecognized selector sent to instance 0x319210'
*** First throw call stack:
(0x340af8bf 0x342ff1e5 0x340b2acb 0x340b1945 0x340b27b8 
0x3748cfa5 0xf051 0x203d1 0x37553f5b 0x374f393b 0x374f37bf 
0x3746d81b 0x37472fb9 0x34bc4ba7 0x36ce3e8d 0x340822dd 
0x340054dd 0x340053a5 0x30889fcd 0x37486743 0xe7a7 0xe74c)
terminate called throwing an exception

ViewController是呈现邮件编辑器的控制器。

以下是我使用的一些代码：

-(void)showHUDWithMessage:(NSString *)msg
{
HUD = [[MBProgressHUD alloc]initWithWindow:self.window];
[self.window addSubview:HUD];
HUD.delegate = self;
UIImage *image;
NSString *labelTextToShow;

//Do something here

UIImageView *imageView = [[[UIImageView alloc]initWithImage:image]autorelease];

HUD.labelText = labelTextToShow;
HUD.customView = imageView;

HUD.mode = MBProgressHUDModeCustomView;
[HUD show:YES];
[HUD hide:YES afterDelay:3.0];
}

-(void)mailFriend:(id)sender
{
MFMailComposeViewController *mailController = [[MFMailComposeViewController alloc]init];
mailController.mailComposeDelegate = self;

[mailController setSubject:@"Mail Subject"];

NSString *emailBody = @"Message";
[mailController setMessageBody:emailBody isHTML:YES];

[self presentModalViewController:mailController animated:YES];
}

-(void)mailComposeController:(MFMailComposeViewController *)controller 
    didFinishWithResult:(MFMailComposeResult)result error:(NSError *)error
{
NSString *msg;
switch (result) {
    case MFMailComposeResultSent:
        msg = @"Sent";
        break;
    case MFMailComposeResultFailed:
        msg = @"Fail";
        break;
    case MFMailComposeResultCancelled:
        msg = @"Cancelled";
        break;
    case MFMailComposeResultSaved:
        msg = @"Cancelled";
        break;
    default:
        break;
}

//Show HUD here
[self showHUDWithMessage:msg];
[self dismissModalViewControllerAnimated:YES];
[controller release];

}

因为如果发送邮件，作曲家视图可以成功解散，HUD也可以正确显示，我真的不知道这里有什么问题......

谢谢！

Answer 1

这很可能是过度释放内存问题。启用NSZombie并测试您的应用。

一些事情：你在哪里创建了控制器？您有责任释放您拥有的对象。您没有控制器对象，因此不要释放它：

[controller release]; // comment this line

在
-(void)mailComposeController:(MFMailComposeViewController *)controller didFinishWithResult:(MFMailComposeResult)result error:(NSError *)error

下一步：

-(void)mailComposeController:(MFMailComposeViewController *)controller 
    didFinishWithResult:(MFMailComposeResult)result error:(NSError *)error
{
NSString *msg = nil; // If result is not equal to any of the case statements then you want to pass nil to [self showHUDWithMessage:msg];
switch (result) {
    case MFMailComposeResultSent:
        msg = @"Sent";
        break;
    case MFMailComposeResultFailed:
        msg = @"Fail";
        break;
    case MFMailComposeResultCancelled:
        msg = @"Cancelled";
        break;
    case MFMailComposeResultSaved:
        msg = @"Cancelled";
        break;
    default:
        break;
}

//Show HUD here
[self showHUDWithMessage:msg];
[self dismissModalViewControllerAnimated:YES];
[controller release];

}

和MFMailComposeViewController *mailController = [[MFMailComposeViewController alloc]init]; -(void)mailFriend:(id)sender自动发布或稍后发布。虽然这与您可能遇到的问题无关。

Answer 2

删除对MBProgressHUD的所有引用，并在您的方法中放入一个简单的NSLog。我打赌我的底部美元MB正在造成这种情况。

如果没有，内存管理是我明显的第二选择。注释掉[控制器发布];

当解雇邮件编辑器并显示HUD时，应用程序崩溃

2 个答案: