Question

我正在编写iPad应用程序并创建了DatePickerView并从UIPopoverController调用它，如下所示：

    DatePickerView *dt = [[DatePickerView alloc] initWithNibName:nil bundle:nil];
    popover =   [[UIPopoverController alloc] initWithContentViewController:dt]; 
    popover.delegate = self;
    [dt release];

    self.popoverController = popover;
    [popover release];

    CGRect popoverRect = [self.view convertRect:[sender frame] fromView:[sender superview]];    
    popoverRect.size.width = MIN(popoverRect.size.width, 100);

    [self.popoverController presentPopoverFromRect:popoverRect inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];

在DatePickerView中，当选择“完成”按钮时，我有以下代码，这基本上是通过使用appdelegate将格式化程序的选定日期发送回主UI：

.H 我

BOutlet UIDatePicker *dtPicker;

-(IBAction) btnSelectClicked:(UIButton *)sender
{

    MachineDetailsView *appDelegate;
    appDelegate = (MachineDetailsView *)[[UIApplication sharedApplication] delegate];

    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:@"MM/dd/YYYY"];

    NSDate *dt = [dtPicker date];

    appDelegate.backPickerStartDate = [formatter stringFromDate:dt];
}

在MachineDetailsView中的

我声明了backPickerStartDate，如下所示：

.h：文件详情

NSString *backPickerStartDate; 

UIPopoverController *popoverController; 

UIPopoverController *popover; 

....
@property(nonatomic, retain) NSString *backPickerStartDate;

....

.m：文件详情

@synthesize backPickerStartDate;

当我点击DatePickerView的“完成”按钮

时，我收到以下错误

2011-03-23 11:46:59.813 iMobile[22492:40b] -[iMobileAppDelegate setBackPickerStartDate:]: unrecognized selector sent to instance 0x8a3dc00
2011-03-23 11:46:59.816 iMobile[22492:40b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[iMobileAppDelegate setBackPickerStartDate:]: unrecognized selector sent to instance 0x8a3dc00'
*** Call stack at first throw:
(
    0   CoreFoundation                      0x00df9be9 __exceptionPreprocess + 185
    1   libobjc.A.dylib                     0x00f4e5c2 objc_exception_throw + 47
    2   CoreFoundation                      0x00dfb6fb -[NSObject(NSObject) doesNotRecognizeSelector:] + 187
    3   CoreFoundation                      0x00d6b366 ___forwarding___ + 966
    4   CoreFoundation                      0x00d6af22 _CF_forwarding_prep_0 + 50
    5   UIKit                               0x00302a6e -[UIApplication sendAction:to:from:forEvent:] + 119
    6   UIKit                               0x003911b5 -[UIControl sendAction:to:forEvent:] + 67
    7   UIKit                               0x00393647 -[UIControl(Internal) _sendActionsForEvents:withEvent:] + 527
    8   UIKit                               0x003921f4 -[UIControl touchesEnded:withEvent:] + 458
    9   UIKit                               0x003270d1 -[UIWindow _sendTouchesForEvent:] + 567
    10  UIKit                               0x0030837a -[UIApplication sendEvent:] + 447
    11  UIKit                               0x0030d732 _UIApplicationHandleEvent + 7576
    12  GraphicsServices                    0x0172fa36 PurpleEventCallback + 1550
    13  CoreFoundation                      0x00ddb064 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 52
    14  CoreFoundation                      0x00d3b6f7 __CFRunLoopDoSource1 + 215
    15  CoreFoundation                      0x00d38983 __CFRunLoopRun + 979
    16  CoreFoundation                      0x00d38240 CFRunLoopRunSpecific + 208
    17  CoreFoundation                      0x00d38161 CFRunLoopRunInMode + 97
    18  GraphicsServices                    0x0172e268 GSEventRunModal + 217
    19  GraphicsServices                    0x0172e32d GSEventRun + 115
    20  UIKit                               0x0031142e UIApplicationMain + 1160
    21  iG2Mobile                           0x000022f2 main + 84
    22  iG2Mobile                           0x00002295 start + 53
)
terminate called after throwing an instance of 'NSException'
Program received signal:  “SIGABRT”.

任何帮助都非常受欢迎。如果需要进一步的细节，请告诉我。

我还在下面将setter方法添加到MachineDetailsView中，但仍然没有用：

-(void)setBackPickerStartDate:(NSString *)newBackPickerStartDate
{

    if (backPickerStartDate != newBackPickerStartDate) {
        backPickerStartDate = newBackPickerStartDate;
    }
}

非常感谢

Answer 1

您已声明已声明并合成backPickerStartDate类中的MachineDetailsView属性，但您在iMobileAppDelegate <{1}}中的btnSelectClicked:实例上调用它/ p>

appDelegate.backPickerStartDate = [formatter stringFromDate:dt];

上面几行，你有这个：

MachineDetailsView *appDelegate;
appDelegate = (MachineDetailsView *)[[UIApplication sharedApplication] delegate];

这是错误的，因为您将指向应用委托的指针转换为指向MachineDetailsView的指针。这不会让你的app委托对象神奇地变成MachineDetailsView对象。你需要的是一个getter方法或属性，它返回你的MachineDetailsView对象（或者找到另一种方法来访问它）。

Answer 2

[iMobileAppDelegate setBackPickerStartDate:]: unrecognized selector sent to instance

根据上面的例外情况，您需要在app委托中声明backPickerStartDate。

由于未捕获的异常'NSInvalidArgumentException而终止应用程序

2 个答案: