浮点值返回 0？答案

【问题标题】：float vlaue returns 0?浮点值返回 0？
【发布时间】：2011-04-02 15:56:10
【问题描述】：

好的，这会有点长，对此我深表歉意，但就是这样。

我正在开发的应用是一个“健身”应用，它可以计算体脂百分比。它有一个男性的一面和一个女性的一面。

我有 3 个男性课程和 3 个女性课程。

 maleBFCinput 
 maleBFCdata
 maleBFCresults

 femaleBFCinput
 femaleBFCdata
 femaleBFCresults

在输入类中，我有用于用户输入的文本字段，在 "maleBFCinput.m" 内进行计算。一旦进行了计算，它们就会被转移到“数据”类，然后转移到“结果”类。

男性的一面完美无瑕。然而，女性方面是问题所在。在 results.xib 上，我有 7 个标签。年龄/身高/体重/最小体重/最大体重/体脂/允许的体脂。

女性结果上的“bodyfat”标签返回 0 。使用我用来计算男性方面的相同技术，它按预期工作，我一直得到 0。

我在输入屏幕上使用浮点数来保存来自较小计算的所有“温度值”，然后进入“体脂计算”。

以下是我拥有的一小段代码。

femaleBFCinput.h

    UITextField *ageInput;
    UITextField *heightInput;
    UITextField *weightInput;
    UITextField *hips1Input;
    UITextField *hips2Input;
    UITextField *hips3Input;
    UITextField *neck1Input;
    UITextField *neck2Input;
    UITextField *neck3Input;
    UITextField *abdomen1Input;
    UITextField *abdomen2Input;
    UITextField *abdomen3Input;

    float heightFactor;
    float weightFactor;
    float abHipsFactor;
    float abFactor;
    float neckFactor;
    float minWeight;
    float maxWeight;
    float maxBodyFatPercentage;
    float abdomenAvg;
    float neckAvg;
    float hipsAvg;
    float abHipsValue;
    float abNeckSubValue;
    float bodyFatPercentage;
    float circumferenceValue;

}

@property(nonatomic,retain) IBOutlet UITextField *ageInput;
@property(nonatomic,retain) IBOutlet UITextField *weightInput;
@property(nonatomic,retain) IBOutlet UITextField *heightInput;
@property(nonatomic,retain) IBOutlet UITextField *abdomen1Input;
@property(nonatomic,retain) IBOutlet UITextField *abdomen2Input;
@property(nonatomic,retain) IBOutlet UITextField *abdomen3Input;
@property(nonatomic,retain) IBOutlet UITextField *neck1Input;
@property(nonatomic,retain) IBOutlet UITextField *neck2Input;
@property(nonatomic,retain) IBOutlet UITextField *neck3Input;
@property(nonatomic,retain) IBOutlet UITextField *hips1Input;
@property(nonatomic,retain) IBOutlet UITextField *hips2Input;
@property(nonatomic,retain) IBOutlet UITextField *hips3Input;

- (float) getMinWeight;
- (float) getMaxWeight;
- (float) getCircumferenceValue;
- (float) getMaxBodyFatPercentage;
- (float) getAbdomenAvg;
- (float) getNeckAvg;
- (float) getAbHipsFactor;
- (float) getBodyFatPercentage;
- (float) getHipsAvg;

femaleBFCinput.m

// Get Abdomen Avg..

- (float) getAbdomenAvg
{
    float abdomen1Float = [abdomen1Input.text floatValue];
    float abdomen2Float = [abdomen2Input.text floatValue];
    float abdomen3Float = [abdomen3Input.text floatValue];

    (abdomenAvg = ((abdomen1Float + abdomen2Float + abdomen3Float) / 3));

    return abdomenAvg;
}

// Get Neck Avg..

- (float) getNeckAvg
{
    float neck1Float = [neck1Input.text floatValue];
    float neck2Float = [neck2Input.text floatValue];
    float neck3Float = [neck3Input.text floatValue];

    (neckAvg = ((neck1Float + neck2Float + neck3Float) / 3));
    return neckAvg;
}

// Get Hips Avg..

- (float) getHipsAvg
{
    float hips1Float = [hips1Input.text floatValue];
    float hips2Float = [hips2Input.text floatValue];
    float hips3Float = [hips3Input.text floatValue];

    (hipsAvg = ((hips1Float + hips2Float + hips3Float) / 3));
    return hipsAvg;
}

//-----Get AbNeck Factor----------------------------------

- (float) getAbHipsFactor
{
    float abTempAvg = [self getAbdomenAvg];
    float hipsTempAvg = [self getHipsAvg];

    (abHipsValue = (abTempAvg + hipsTempAvg));

    return abHipsValue;
}


//----Get Circumference Value-----------------------------

- (float) getCircumferenceValue
{

    (circumferenceValue = (abHipsValue - neckAvg));

    return circumferenceValue;
}

// Get Body Fat Percentage..

- (float) getBodyFatPercentage
{
    float circumferenceTempValue = [self getCircumferenceValue];
    float heightTempValue = [heightInput.text floatValue];


    if (heightTempValue >= 58.00 && heightTempValue <= 58.49) {
        if (circumferenceTempValue >= 45.00 && circumferenceTempValue <= 45.49) {bodyFatPercentage = 19;}
        else if (circumferenceTempValue >= 45.50 && circumferenceTempValue <= 45.99) {bodyFatPercentage = 20;}
        else if (circumferenceTempValue >= 46.00 && circumferenceTempValue <= 46.49) {bodyFatPercentage = 21;}
        else if (circumferenceTempValue >= 46.50 && circumferenceTempValue <= 46.99) {bodyFatPercentage = 21;}

 else if (heightTempValue >= 77.50 && heightTempValue <= 77.99) {
        if (circumferenceTempValue >= 53.50 && circumferenceTempValue <= 53.99) {bodyFatPercentage = 19;}
        else if (circumferenceTempValue >= 54.00 && circumferenceTempValue <= 54.49) {bodyFatPercentage = 20;}
        else if (circumferenceTempValue >= 54.50 && circumferenceTempValue <= 54.99) {bodyFatPercentage = 20;}
        else if (circumferenceTempValue >= 55.00 && circumferenceTempValue <= 55.49) {bodyFatPercentage = 21;}

        etc..
        etc.. (theres about 4000ish lines of if / else if statements in here so i just pasted a few so you see what i have)

        else if (circumferenceTempValue >= 77.50 && circumferenceTempValue <= 77.99) {bodyFatPercentage = 45;}
        else if (circumferenceTempValue >= 78.00 && circumferenceTempValue <= 78.49) {bodyFatPercentage = 46;}
        else if (circumferenceTempValue >= 78.50 && circumferenceTempValue <= 78.99) {bodyFatPercentage = 46;}
        else if (circumferenceTempValue >= 79.00 && circumferenceTempValue <= 79.49) {bodyFatPercentage = 47;}
    }

    return bodyFatPercentage;

}



- (IBAction)calculate:(id)sender {

    FemaleBFCresults *femaleBFCresults = [[FemaleBFCresults alloc] initWithNibName:@"FemaleBFCresults" bundle:nil];

    FemaleBFCdata *femaleBFCData = [[FemaleBFCdata alloc] init];
    femaleBFCresults.femaleBFCdata = femaleBFCData;

    femaleBFCresults.femaleBFCdata.ageInput = ageInput.text;
    femaleBFCresults.femaleBFCdata.heightInput = heightInput.text;
    femaleBFCresults.femaleBFCdata.weightInput = weightInput.text;

    NSString *minWeightString = [[NSString alloc] initWithFormat:@"%.0f", [self getMinWeight]];
    femaleBFCresults.femaleBFCdata.minWeight = minWeightString;
    [minWeightString release];

    NSString *maxWeightString = [[NSString alloc] initWithFormat:@"%.0f", [self getMaxWeight]];
    femaleBFCresults.femaleBFCdata.maxWeight = maxWeightString;
    [maxWeightString release];

    NSString *maxBodyFatString = [[NSString alloc] initWithFormat:@"%.0f", [self getMaxBodyFatPercentage]];
    femaleBFCresults.femaleBFCdata.maxBodyFat = maxBodyFatString;
    [maxBodyFatString release];

    NSString *bodyFatString = [[NSString alloc] initWithFormat:@"%.0f", [self getBodyFatPercentage]];
    femaleBFCresults.femaleBFCdata.bodyFat = bodyFatString;
    [bodyFatString release];


    femaleBFCresults.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
    [self presentModalViewController:femaleBFCresults animated:YES];
    [self.view removeFromSuperview];
    [femaleBFCresults release];

}

femaleBFCdata.h

@interface FemaleBFCdata : NSObject {


    NSString *ageInput;
    NSString *heightInput;
    NSString *weightInput;
    NSString *neckAvg;
    NSString *abAvg;
    NSString *hipsAvg;
    NSString *abHipFactor;
    NSString *bodyFat;
    NSString *maxBodyFat;
    NSString *minWeight;
    NSString *maxWeight;
    NSString *circumference;

}

@property (nonatomic, retain) NSString *ageInput;
@property (nonatomic, retain) NSString *heightInput;
@property (nonatomic, retain) NSString *weightInput;
@property (nonatomic, retain) NSString *neckAvg;
@property (nonatomic, retain) NSString *abAvg;
@property (nonatomic, retain) NSString *hipsAvg;
@property (nonatomic, retain) NSString *abHipFactor;
@property (nonatomic, retain) NSString *bodyFat;
@property (nonatomic, retain) NSString *maxBodyFat;
@property (nonatomic, retain) NSString *minWeight;
@property (nonatomic, retain) NSString *maxWeight;
@property (nonatomic, retain) NSString *circumference;

femaleBFCdata.m

@synthesize ageInput;
@synthesize heightInput;
@synthesize weightInput;
@synthesize neckAvg;
@synthesize abAvg;
@synthesize hipsAvg;
@synthesize abHipFactor;
@synthesize bodyFat;
@synthesize maxBodyFat;
@synthesize minWeight;
@synthesize maxWeight;
@synthesize circumference;

- (void)dealloc {

    self.ageInput = nil;
    self.heightInput = nil;
    self.weightInput = nil;
    self.neckAvg = nil;
    self.abAvg = nil;
    self.hipsAvg = nil;
    self.abHipFactor = nil;
    self.bodyFat = nil;
    self.maxBodyFat = nil;
    self.minWeight = nil;
    self.maxWeight = nil;
    self.circumference = nil;
    [super dealloc];
}

femaleBFCresults.h

@interface FemaleBFCresults : UIViewController {

    FemaleBFCdata *femaleBFCdata;
    UILabel *displayAge;
    UILabel *displayHeight;
    UILabel *displayWeight;
    UILabel *displayBodyFat;
    UILabel *displayMaxBodyFat;
    UILabel *displayMinWeight;
    UILabel *displayMaxWeight;

}

@property (nonatomic, retain) FemaleBFCdata *femaleBFCdata;
@property (nonatomic, retain) IBOutlet UILabel *displayAge;
@property (nonatomic, retain) IBOutlet UILabel *displayHeight;
@property (nonatomic, retain) IBOutlet UILabel *displayWeight;
@property (nonatomic, retain) IBOutlet UILabel *displayBodyFat;
@property (nonatomic, retain) IBOutlet UILabel *displayMaxBodyFat;
@property (nonatomic, retain) IBOutlet UILabel *displayMinWeight;
@property (nonatomic, retain) IBOutlet UILabel *displayMaxWeight;

- (IBAction)goBack:(id)sender;

@end

femaleBFCdata.m

@synthesize femaleBFCdata;
@synthesize displayAge;
@synthesize displayHeight;
@synthesize displayWeight;
@synthesize displayBodyFat;
@synthesize displayMaxBodyFat;
@synthesize displayMinWeight;
@synthesize displayMaxWeight;

- (void)viewDidLoad {

    self.displayAge.text = femaleBFCdata.ageInput;
    self.displayHeight.text = femaleBFCdata.heightInput;
    self.displayWeight.text = femaleBFCdata.weightInput;
    self.displayBodyFat.text = femaleBFCdata.bodyFat;
    self.displayMaxBodyFat.text = femaleBFCdata.maxBodyFat;
    self.displayMinWeight.text = femaleBFCdata.minWeight;
    self.displayMaxWeight.text = femaleBFCdata.maxWeight;

    [super viewDidLoad];
}

- (void)dealloc {

    [displayAge dealloc];
    [displayHeight dealloc];
    [displayWeight dealloc];
    [displayBodyFat dealloc];
    [displayMaxBodyFat dealloc];
    [displayMinWeight dealloc];
    [displayMaxWeight dealloc];

    [super dealloc];
}

就像我说的那样，男性课程的完成方式完全相同，这是完美的。但是在女班上，我的成绩班一直得到 0 的回报，我似乎不知道为什么。我已经为此工作了几个月。我请了几个星期的假，我想在我休息之前我已经完成了这项工作，但我想我没有。有没有人有任何想法可以帮助我解决这个问题？

【问题讨论】：

标签： objective-c cocoa ios4 xcode4

【解决方案1】：

您绝对确定您的输入字段出口都已连接吗？向 nil 出口询问其 -floatValue 将给您一个 nil（解释为 0）响应。

【讨论】：

好的。然后在你的代码中设置一个断点“跳过”代码。现在是学习如何使用 GDB 的最佳时机。顺便说一句，你确定你的类层次结构很聪明吗？将女性和男性类的公共代码重构为一个公共超类以使其更易于维护，会不会是更好的解决方案？
你绝对必须学会使用调试器。没有崩溃/异常/无论如何并不意味着没有问题。在触发所有这些行为的任何操作上设置断点，并逐步完成，确保检查所有相关变量以确保它们的值是预期的。调试器是每个开发人员的必须。
房间用完了。补充：相信我，只要在时间和理解上投入一点点，一个全新的世界就会在你解决代码问题方面向你敞开。就像白天和黑夜一样。
@Shaun Hornsby：你可以在任何你喜欢的地方设置它们，只要它在一个语句块内（在函数或方法定义之外放置断点是没有用的）。在您最终使用该值之前设置您的第一个断点；如果您发现插座未连接或发现其他问题，请通过您的程序在连续的调试运行中逆向解决问题。
@shaun hornsby 我知道设计或多或少“聪明”的类层次结构很复杂。通常，开发人员首先会构建一个过于复杂的类结构，最终难以维护。这总是一个权衡。如果您想了解 Cocoa 的更深层次原理，请查看《可可设计模式》一书。

【解决方案2】：

好的，所以我通过四舍五入我在到达“bodyfatcalculations”之前计算的所有“平均值”来实现它

 - (float)getabHipAvg {
     float ab1 = [abdomen1Input.text floatValue];
     float ab2 = [abdomen2Input.text floatValue];
     float ab3 = [abdomen3Input.text floatValue];
     float hip1 = [hips1Input.text floatValue];
     float hip2 = [hips2Input.text floatValue];
     float hip3 = [hips3Input.text floatValue];

     (abHipAvg = (((ab1+ab2+ab3)/3)+((hip1+hip2+hip3)/3)));
     abHipAvg = roundf(abHipAvg * 2.0f) / 2.0f;

     return abHipAvg; }

 - (float)getneckAvg {
     float neck1 = [neck1Input.text floatValue];
     float neck2 = [neck2Input.text floatValue];
     float neck3 = [neck3Input.text floatValue];

     (neckAvg = ((neck1+neck2+neck3)/3));
     neckAvg = roundf(neckAvg * 2.0f) / 2.0f;

     return neckAvg;
      }

 - (float)getCircumferenceValue {
     float abHipTempAvg = [self getabHipAvg];
     float neckTempAvg = [self getneckAvg];

     (circumferenceValue = (abHipTempAvg - neckTempAvg));
     circumferenceValue = roundf(circumferenceValue *2.0f) / 2.0f;

    return circumferenceValue; }

所以，是的，这就是我的解决方案，所有 if/else if 语句都没有错，事实上，除以 3 得到平均值时，我得到的小数比我需要的长得多，因此通过将它们四舍五入为最近的一半解决了我的问题。现在我得到了应该出来的答案。

感谢大家的帮助！！

【讨论】：