ios - 如何在目标 c 中将小数合并到计算器中？

Question

以下是我在 Xcode 中使用 Objective C 制作的应用程序。这是 ViewController.m

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    valueString = @"";
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

-(IBAction)tappedClear:(id)sender
{
    total = 0;
    valueString = @"";
    label.text = @"0";
}
-(IBAction)tappedNumber:(UIButton*)btn
{
    int num = btn.tag;
    if (num == 0 && total == 0) {
        return;
    }
    if (lastButtonWasMade) {
        lastButtonWasMade = false;
        valueString = @"";
    }
    NSString *numAsString = [NSString stringWithFormat:@"%i",num];
    valueString = [valueString stringByAppendingString:numAsString];
    NSNumberFormatter *formatter = [NSNumberFormatter new];
    [formatter setNumberStyle:NSNumberFormatterDecimalStyle];
    NSNumber *n = [formatter numberFromString:valueString];
    label.text = [formatter stringFromNumber:n];
    if (total == 0) {
        total = [valueString intValue];
    }
}
-(IBAction)tappedPlus:(id)sender
{
    [self setMode:1];
}
-(IBAction)tappedMinues:(id)sender
{
    [self setMode:-1];
}
-(IBAction)tappedEquals:(id)sender
{
    if (mode == 0) {
        return;
    }
    if (mode == 1) {
        total +=[valueString intValue];
    }
    if (mode == -1) {
        total -=[valueString intValue];
    }
    if (mode == 2) {
        total *=[valueString intValue];
    }
    if (mode == 1/2) {
        total /=[valueString intValue];
    }
    if (mode == 10) {
        total *=[valueString intValue];
    }
    valueString = [NSString stringWithFormat:@"%i",total];
    NSNumberFormatter *formatter = [NSNumberFormatter new];
    [formatter setNumberStyle:NSNumberFormatterDecimalStyle];
    NSNumber *n = [formatter numberFromString:valueString];
    label.text = [formatter stringFromNumber:n];
    mode = 0;

}
-(IBAction)tappedMultiply:(id)sender
{
    [self setMode:2];
}
-(IBAction)tappedDivide:(id)sender
{
    [self setMode:1/2];
}    
-(IBAction)tappedDecimal:(id)sender
{

}
-(IBAction)tappedPercent:(id)sender
{
    [self setMode:10];
}

-(void)setMode:(int)m
{
    if (total == 0) {
        return;
    }
    mode = m;
    lastButtonWasMade = true;
    total = [valueString intValue];
}

@end

以下是我的 ViewController.h

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController
{
    int total;
    int mode;
    NSString *valueString;
    IBOutlet UILabel *label;
BOOL lastButtonWasMade;
}
-(IBAction)tappedClear:(id)sender;
-(IBAction)tappedNumber:(UIButton*)btn;
-(IBAction)tappedPlus:(id)sender;
-(IBAction)tappedMinues:(id)sender;
-(IBAction)tappedEquals:(id)sender;
-(IBAction)tappedMultiply:(id)sender;
-(IBAction)tappedDivide:(id)sender;
-(IBAction)tappedDecimal:(id)sender;
-(IBAction)tappedPercent:(id)sender;

@end

我在 Main.storyboard 中标记了每个按钮，以消除多余的代码。基本上，我想要一个可以工作的小数按钮、一个可以工作的百分比按钮和一个可以工作的除法按钮。我还想在按下等号后输入新数字时清除屏幕。

我会导入图片，但我没有声望。a