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[英]GetViewForHeader works in the simulator but not working on the device
[英]ECGraph not working on device, but works on simulator
有什么理由說為什么ECGraph可以在模擬器上正常運行,但是當我在我的設備上運行它時卻給我這個錯誤:
2012-08-24 01:57:18.543 Portfolio[3538:907] *** -[__NSCFCalendar components:fromDate:toDate:options:]: fromDate cannot be nil
I mean really, what do you think that operation is supposed to mean with a nil fromDate?
An exception has been avoided for now.
A few of these errors are going to be reported with this complaint, then further violations will simply silently do whatever random thing results from the nil.
Here is the backtrace where this occurred this time (some frames may be missing due to compiler optimizations):
(
0 CoreFoundation 0x37a1d78f <redacted> + 86
1 Portfolio 0x000a0d1f -[ECGraph(Private) getDaysFrom:To:] + 202
2 Portfolio 0x000a1577 -[ECGraph(Private) getXDaysFromLines:minDate:] + 502
3 Portfolio 0x000a2623 -[ECGraph drawCurveWithLines:lineWidth:color:] + 978
4 Portfolio 0x000a716f -[GraphView drawRect:] + 2682
5 UIKit 0x38b1811d <redacted> + 364
6 QuartzCore 0x39468035 <redacted> + 112
7 QuartzCore 0x39467771 <redacted> + 1808
8 QuartzCore 0x39466f45 <redacted> + 980
9 QuartzCore 0x39466a7b <redacted> + 202
10 QuartzCore 0x3953a9f5 <redacted> + 24
11 QuartzCore 0x394663d3 <redacted> + 238
12 QuartzCore 0x39466119 <redacted> + 316
13 QuartzCore 0x3945dfe1 <redacted> + 60
14 CoreFoundation 0x37a4f18d <redacted> + 20
15 CoreFoundation 0x37a4d3f9 <redacted> + 276
16 CoreFoundation 0x37a4d74f <redacted> + 742
17 CoreFoundation 0x379cbc1d CFRunLoopRunSpecific + 356
18 CoreFoundation 0x379cbaa9 CFRunLoopRunInMode + 104
19 GraphicsServices 0x3a88f33b GSEventRunModal + 74
20 UIKit 0x38b35535 UIApplicationMain + 1120
21 Portfolio 0x00094e7d main + 152
22 Portfolio 0x00094de0 start + 40
)
你試圖從這樣的nil NSDate獲取NSDateComponents:
NSCalendar* gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDate* fromDate = nil;
NSDate* toDate = [NSDate date];
unsigned int components = NSYearCalendarUnit | NSDayCalendarUnit | NSMonthCalendarUnit | NSWeekCalendarUnit | NSWeekdayCalendarUnit | NSHourCalendarUnit;
NSDateComponents* dateComponents = [gregorian components:uintFlags fromDate:fromDate toDate:toDate options:0];
可能一個簡單的檢查可能是有用的:
NSDate* fromDate = nil;
NSDate* toDate = [NSDate date];
NSDateComponents* dateComponents = nil;
if(fromDate != nil)
{
NSCalendar* gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
unsigned int components = NSYearCalendarUnit | NSDayCalendarUnit | NSMonthCalendarUnit | NSWeekCalendarUnit | NSWeekdayCalendarUnit | NSHourCalendarUnit;
dateComponents = [gregorian components:uintFlags fromDate:fromDate toDate:toDate options:0];
}
您的設備使用的區域格式與模擬器不同。
如果你匹配(在Settings -> General -> International
),那么他們應該顯示相同的結果。 在我的情況下,當這樣做時,他們都失敗了,但模擬器沒有提供與設備相同的日志,所以我幾乎錯過了它。
我假設您正在使用NSDateFormatter
將某些字符串日期格式化為NSDate。 在這種情況下,您必須確保這不取決於手機的區域類型,並將解決方案設置為始終相同,無論您是誰。
[df setLocale:([[NSLocale alloc] initWithLocaleIdentifier:@"en_UK"])];
// df being the NSDateFormatter-object
這告訴格式化程序使用英國標准進行格式化,這在我的案例中是必需的。 輸入您需要的國家代碼,即en_US
等。
性病
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