以下方法从 UITextField 获取输入并将其格式化以供显示。这段代码多年来一直完美运行,但刚刚在使用 iOS 8.1 的 iPhone 6 Plus 上报告了一个问题。它每次都会发生在用户身上,但我无法重现它。我相信它与 iOS 8 上的 NSNumber/NSDecimalNumber 转换和格式化有关,可能是针对 64 位应用程序/设备。
用于输入的键盘是数字键盘,因此可以在文本字段中输入的唯一文本是数字 0-9 和“删除”。
根据用户的说法,这就是正在发生的事情:
我正在尝试输入 250 美元的预算金额。当我最初将其拉起时显示为 0.00。然后,一旦我输入 2,它就会显示 220.02,然后当我输入 5 时,它会显示 2,200.25,然后当我输入 0 时,它会显示 22,002.50,如果我尝试擦除任何数字,它会显示一个非常大的数字。
据我测试,下面的代码在模拟器中的每台设备(包括 iPhone 6 Plus)上都与 iOS 8.1 完美配合。它也适用于装有 iOS 8.1 的 iPhone 5S 设备(64 位)。我没有 iPhone 6 Plus 设备。
我是否遗漏了某些人看到的可能导致此错误的内容?
编辑:这可能是因为 decimalNumberWithMantissa 参数应该是 unsigned long long 而我使用的是 NSInteger?这会导致问题吗?如果是这样,为什么它在 iPhone 6 Plus 上的 iOS 8.1 之前一直有效?如果可以的话,我会自己检查一下...
entryField UITextField 初始化如下:
entryField.text = [NSString stringWithFormat:@"%@", [[[ObjectsHelper sharedManager] currencyFullFormatter] stringFromNumber:[NSDecimalNumber zero]]];
这是其余的相关代码:
#define MAX__NUMBER_LENGTH 10
- (BOOL)textField:(UITextField *)textFieldHere shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
__ENTERING_METHOD__
NSMutableString *mstring = [[NSMutableString alloc] initWithString:[entryField text]];
if([string length] > 0){
//add case
[mstring insertString:string atIndex:range.location];
}
else {
//delete case - the length of replacement string is zero for a delete
[mstring deleteCharactersInRange:range];
}
NSString *clean_string = [[mstring componentsSeparatedByCharactersInSet:
[[NSCharacterSet decimalDigitCharacterSet] invertedSet]]
componentsJoinedByString:@""];
//clean up mstring since it's no longer needed
if ((clean_string.length >= MAX__NUMBER_LENGTH && range.length == 0) || ([clean_string length] == 0 && [string isEqualToString:@"0"]))
{
return NO; // return NO to not change text
}
else {
//get the cleaned price in the form of a NSNumber - it has not yet been scaled
NSNumber *priceNumberBeforeScale = [[DateHelper decimalFormatter] numberFromString:clean_string];
self.budgetIntNumber = priceNumberBeforeScale;
//get the cleaned price in the form of an integer - it has not yet been scaled
NSInteger priceIntBeforeScale = [priceNumberBeforeScale integerValue];
//scale the price for currency
NSDecimalNumber *priceScaled = [NSDecimalNumber decimalNumberWithMantissa:priceIntBeforeScale exponent:(0-[[[ObjectsHelper sharedManager] currencyScale] integerValue]) isNegative:NO];
//now format the price for currency
//and get the grouping separators added in and put it in the UITextField
entryField.text = [[[ObjectsHelper sharedManager] currencyFullFormatter] stringFromNumber:priceScaled];
//always return no since we are manually changing the text field
return NO;
}
}
来自 DateHelper.m:
+ (NSNumberFormatter *)decimalFormatter {
__ENTERING_METHOD__
NSNumberFormatter *decimalFormatter = [[NSNumberFormatter alloc] init];
[decimalFormatter setFormatterBehavior:NSNumberFormatterBehavior10_4];
[decimalFormatter setNumberStyle:NSNumberFormatterDecimalStyle];
return decimalFormatter;
}
来自 ObjectsHelper.m:
- (NSNumberFormatter*)currencyFullFormatter {
__ENTERING_METHOD__
if (currencyFullFormatter != nil) {
return currencyFullFormatter;
}
currencyFullFormatter = [[NSNumberFormatter alloc] init];
[currencyFullFormatter setFormatterBehavior:NSNumberFormatterBehavior10_4];
[currencyFullFormatter setNumberStyle:NSNumberFormatterCurrencyStyle];
return currencyFullFormatter;
}
- (NSNumber*)currencyScale {
__ENTERING_METHOD__
if (currencyScale != nil) {
return currencyScale;
}
self.currencyScale = [NSNumber numberWithInteger:[[[ObjectsHelper sharedManager] currencyFullFormatter] maximumFractionDigits]];
return currencyScale;
}
编辑:似乎这个答案可能在正确的轨道上,只是不完全确定在这里会如何翻译。会改变
//get the cleaned price in the form of an integer - it has not yet been scaled
NSInteger priceIntBeforeScale = [priceNumberBeforeScale integerValue];
//scale the price for currency
NSDecimalNumber *priceScaled = [NSDecimalNumber decimalNumberWithMantissa:priceIntBeforeScale exponent:(0-[[[ObjectsHelper sharedManager] currencyScale] integerValue]) isNegative:NO];
至
//scale the price for currency
NSDecimalNumber *priceScaled = [NSDecimalNumber decimalNumberWithMantissa:[priceNumberBeforeScale unsignedLongLongValue] exponent:(0-[[[ObjectsHelper sharedManager] currencyScale] integerValue]) isNegative:NO];
有可能解决问题吗?