iphone - 此代码适用于 iOS4.3，不适用于 iOS5

Question

以下代码在 iOS4.3 iPhone 和 iPad 以及 iOS5 iPhone 上按预期工作，但在 iOS5 iPad 上崩溃。当应用程序的先前运行被取消时，这是我在基于选项卡的应用程序中调用的第一个 View 所调用的。用户可以继续之前的运行或重置。我尝试将此代码移至 -viewWillAppear 和 -viewDidAppear 割线，但无济于事。还有其他人经历过吗？ (顺便说一句，我已经确认了 XIB 中的所有连接，以确保此 UniversalApp 的 iPad 部分没有问题。

- (void)viewDidLoad {

 BOOL     continueYesNo;

 NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];

 continueYesNo = [prefs boolForKey:@"keyContinueMeeting"];     

 if (continueYesNo) {

      NSString *message_continue = [[NSString alloc] initWithFormat:@"Do you want to Continue the Prior event"];

      UIActionSheet *actionSheet = [[UIActionSheet alloc] 

           initWithTitle:message_continue 

           delegate:self

           cancelButtonTitle:@"Reset" 

           destructiveButtonTitle:@"Continue Meeting"

           otherButtonTitles:nil];

    [actionSheet showFromTabBar:self.tabBarController.tabBar];  // This is the line that crashes.  The program checks for a terminated APP and status in preferences

 }

 else {

      resetStuff.hidden = YES;

 }

}

这是崩溃的文本 -

Current language:  auto; currently objective-c

2011-10-12 21:02:55.530 浪费时间[3884:17603] * -[UIActionSheet showInView:]、/SourceCache/UIKit_Sim/UIKit-1912.3/UIActionSheet.m:4630 中断言失败2011-10-12 21:02:55.532 应用程序名称[3884:17603] 由于未捕获的异常“NSInternalInconsistencyException”而终止应用程序，原因:“无效参数不满足: View ” !=零'** 首先抛出调用堆栈:(0x1d87052 0x1f18d0a 0x1d2fa78 0x2742db 0x90b47e 0x90b122 0x90b356 0x90b653 0x6fe1 0x60064e 0x61bb89 0x61b9bd 0x619f8a 0x619e2 f 0x617ffb 0x61885a 0x601fbf 0x60221b 0x6030f1 0x571fec 0x577572 0x57172b 0x2b86 0x5389d6 0x5398a6 0x548743 0x5491f8 0x53caa9 0x2315fa9 0x1d5b1c5 0x1cc0022 0x1cbe90a 0x1cbddb4 0x1cbdccb 0x5392a7 0x53aa9b 0x2abd 0x2325)终止调用抛出异常(gdb

Blockquote

这是代表.h

#import <UIKit/UIKit.h>    
@interface W_AppDelegate : NSObject <UIApplicationDelegate> {
        UIWindow *window;
        UITabBarController *rootController;
        float   floatVal;
        NSDate  *currentTime;
        NSDate  *previousTime;
        NSDate  *currentQTime;
        NSDate  *previousQTime;
        BOOL    continueMeeting;
    }

    @property (nonatomic, retain) IBOutlet UIWindow *window;
    @property (nonatomic, retain) IBOutlet UITabBarController *rootController;
    @property (nonatomic, readwrite) float floatVal;
    @property (nonatomic, readwrite) BOOL continueMeeting;
    @property (nonatomic, retain) NSDate *currentTime;
    @property (nonatomic, retain) NSDate *previousTime;
    @property (nonatomic, retain) NSDate *currentQTime;
    @property (nonatomic, retain) NSDate *previousQTime;
    @end

还有.m

#import "W.h"


@implementation W_AppDelegate

@synthesize window;
@synthesize rootController;
@synthesize floatVal;
@synthesize currentTime;
@synthesize previousTime;
@synthesize currentQTime;
@synthesize previousQTime;
@synthesize continueMeeting;

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
    [window addSubview:rootController.view];
    [window makeKeyAndVisible]; 
    return YES;
}

@end

Answer 1

尝试调用你的[super viewDidLoad]；第一的。您的 View 可能尚未设置得足以推送 actionSheet。