计算器

 AppDelegate.h

#import <UIKit/UIKit.h>
@class CustomButton;//在.h引入头文件全部用@class,@class作用是声明有这么一个类
enum fuhaomeiju {
    jia,
    jian,
    cheng,
    chu,
    kong
};
@interface AppDelegate : UIResponder <UIApplicationDelegate>
{
    CGFloat _perfixValue;  //perfixValue:上次所输入的内容
    BOOL _lastEnterType;  //上次所输入的类型,YES代表操作符,NO代表数字
}
@property (nonatomic,assign) int fuhao;
@property (strong, nonatomic) UIWindow * window;
@property (retain,nonatomic) UILabel * label;
@end

AppDelegate.m

#import "AppDelegate.h"
#import "CustomButton.h"
@implementation AppDelegate
- (void)dealloc
{
    [_window release];
    _window = nil;
    [self.label release];
    _label = nil;
                       
    [super dealloc];
}
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]autorelease];
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor grayColor];
    [self.window makeKeyAndVisible];
                       
    _fuhao = kong;
                       
    [self Calculator];
    return YES;
}
- (void)Calculator
{
    _lastEnterType = NO;//设置默认初始值为NO;在整个程序开始的时候写
                       
    //显示框
    self.label = [[UILabel alloc]initWithFrame:CGRectMake(20, 30, 280, 50) ];
    [_label setBackgroundColor:[UIColor whiteColor]];
    [_label setText:@" "];//开头显示null解决办法1
    self.label.layer.borderWidth =4;//边框宽度=4;layer属于UIView
    self.label.layer.borderColor = [UIColor redColor].CGColor;//边框颜色红色
    UIFont * font = [UIFont systemFontOfSize:30];
    [self.label setFont:font];
    [self.window addSubview:self.label];
    [self.label release];
    //1
    CustomButton * button = [[CustomButton alloc]initWithFrame:CGRectMake(20, 100, 60, 60) name:@"1"];
    [button addTarget:self action:@selector(buttonAciton:) forControlEvents:UIControlEventTouchUpInside];
    [self.window addSubview:button];
                       
    //2
    CustomButton * button3 = [[CustomButton alloc]initWithFrame:CGRectMake(95, 100, 60, 60) name:@"2"];
    [button3 addTarget:self action:@selector(buttonAciton:) forControlEvents:UIControlEventTouchUpInside];
    [self.window addSubview:button3];
    //3
    CustomButton * button4 = [[CustomButton alloc]initWithFrame:CGRectMake(170, 100, 60, 60) name:@"3"];
    [button4 addTarget:self action:@selector(buttonAciton:) forControlEvents:UIControlEventTouchUpInside];
    [self.window addSubview:button4];
    //4
    CustomButton * button5 = [[CustomButton alloc]initWithFrame:CGRectMake(20, 180, 60, 60) name:@"4"];
    [button5 addTarget:self action:@selector(buttonAciton:) forControlEvents:UIControlEventTouchUpInside];
    [self.window addSubview:button5];
    //5
    CustomButton * button6 = [[CustomButton alloc]initWithFrame:CGRectMake(95, 180, 60, 60) name:@"5"];
    [button6 addTarget:self action:@selector(buttonAciton:) forControlEvents:UIControlEventTouchUpInside];
    [self.window addSubview:button6];
    //6
    CustomButton * button7 = [[CustomButton alloc]initWithFrame:CGRectMake(170, 180, 60, 60) name:@"6"];
    [button7 addTarget:self action:@selector(buttonAciton:) forControlEvents:UIControlEventTouchUpInside];
    [self.window addSubview:button7];
    //7
    CustomButton * button8 = [[CustomButton alloc]initWithFrame:CGRectMake(20, 260, 60, 60) name:@"7"];
    [button8 addTarget:self action:@selector(buttonAciton:) forControlEvents:UIControlEventTouchUpInside];
    [self.window addSubview:button8];
    //8
    CustomButton * button9 = [[CustomButton alloc]initWithFrame:CGRectMake(95, 260, 60, 60) name:@"8"];
    [button9 addTarget:self action:@selector(buttonAciton:) forControlEvents:UIControlEventTouchUpInside];
    [self.window addSubview:button9];
    //9
    CustomButton * button0 = [[CustomButton alloc]initWithFrame:CGRectMake(170, 260, 60, 60) name:@"9"];
    [button0 addTarget:self action:@selector(buttonAciton:) forControlEvents:UIControlEventTouchUpInside];
    [self.window addSubview:button0];
    //0
    CustomButton * button11 = [[CustomButton alloc]initWithFrame:CGRectMake(20, 340, 60, 60) name:@"0"];
    [button11 addTarget:self action:@selector(buttonAction0:) forControlEvents:UIControlEventTouchUpInside];
    button11.layer.borderWidth = 3;
    button11.layer.borderColor=[UIColor cyanColor].CGColor;
    [self.window addSubview:button11];
    //C
    CustomButton * c = [[CustomButton alloc]initWithFrame:CGRectMake(95, 340, 60, 60) name:@"C"];
    [c addTarget:self action:@selector(buttonActionC)forControlEvents:UIControlEventTouchUpInside];
    c.layer.borderWidth = 3;
    c.layer.borderColor=[UIColor yellowColor].CGColor;
    [self.window addSubview:c];
    //+
    CustomButton * button1 = [[CustomButton alloc]initWithFrame:CGRectMake(240, 100, 60, 60) name:@"+"];
                       
    [button1 addTarget:self action:@selector(addAction:) forControlEvents:UIControlEventTouchUpInside];
    button1.layer.borderWidth = 3;
    button1.layer.borderColor=[UIColor blueColor].CGColor;
    [self.window addSubview:button1];
    //-
    CustomButton * button12 = [[CustomButton alloc]initWithFrame:CGRectMake(240, 180, 60, 60) name:@"-"];
                       
    [button12 addTarget:self action:@selector(addAction:) forControlEvents:UIControlEventTouchUpInside];
    button12.layer.borderWidth = 3;
    button12.layer.borderColor=[UIColor blueColor].CGColor;
    [self.window addSubview:button12];
    //*
    CustomButton * button13 = [[CustomButton alloc]initWithFrame:CGRectMake(240, 260, 60, 60) name:@"*"];
                       
    [button13 addTarget:self action:@selector(addAction:) forControlEvents:UIControlEventTouchUpInside];
    button13.layer.borderWidth = 3;
    button13.layer.borderColor=[UIColor blueColor].CGColor;
    [self.window addSubview:button13];
    //"/"
    CustomButton * button14 = [[CustomButton alloc]initWithFrame:CGRectMake(240, 340, 60, 60) name:@"/"];
                       
    [button14 addTarget:self action:@selector(addAction:) forControlEvents:UIControlEventTouchUpInside];
    button14.layer.borderWidth = 3;
    button14.layer.borderColor=[UIColor blueColor].CGColor;
    [self.window addSubview:button14];
                       
                       
    //=
    CustomButton * button2 = [[CustomButton alloc]initWithFrame:CGRectMake(170, 340, 60, 60) name:@"="];
                       
    [button2 addTarget:self action:@selector(equaAction) forControlEvents:UIControlEventTouchUpInside];
    button2.layer.borderWidth = 3;
    button2.layer.borderColor=[UIColor orangeColor].CGColor;
    [self.window addSubview:button2];
                           
    }
- (void)buttonAciton:(CustomButton *)button//形参
{
                       
    NSString * value = button.currentTitle;
                       
    if (_lastEnterType) {
        [self.label setText:@""];//如果输入的是数字label清空
        [self.label setText:value];//值赋给value
        _lastEnterType = NO;
    }else{
                           
        if ([_label.text length] == 0) {//开头显示null解决办法2
            [_label setText:@""];
        }
        NSString * endValue = [NSString stringWithFormat:@"%@%@",_label.text,value];//拼接字符串
        [_label setText:endValue];
                           
    }
}
- (void)buttonAction0:(CustomButton *)button0
{
    NSString * value = button0.currentTitle;
    if (_lastEnterType) {
        [_label setText:value];
        _lastEnterType = NO;
    }else{
        if (_label.text == nil) {
            [_label setText:@"0"];
        }
        NSString * endValue = [NSString stringWithFormat:@"%@%@",_label.text,value];
        [_label setText:endValue];
    }
}
- (void)buttonActionC
{
    _label.text = @"";
    _lastEnterType = YES;
}
//+
- (void)addAction:(CustomButton *)button
{
    NSString * current1 = _label.text;//保存屏幕上的内容
                       
    _perfixValue = [current1 floatValue];//把NSString的类型转换成float类型;
                       
    _lastEnterType = YES;
    if ([button.currentTitle isEqualToString:@"+"]) {
        _fuhao = jia;
    }
    if ([button.currentTitle isEqualToString:@"-"]) {
        _fuhao = jian;
    }
    if ([button.currentTitle isEqualToString:@"*"]) {
        _fuhao = cheng;
    }
    if ([button.currentTitle isEqualToString:@"/"]) {
        _fuhao = chu;
    }
}
// =
- (void)equaAction
{
                       
    NSString * current = _label.text;
    CGFloat currentValue = [current floatValue];//转换成float类型
                       
    CGFloat endValue = 0;
    switch (_fuhao) {
        case jia:
            endValue = _perfixValue + currentValue;
            break;
                               
        case jian:
            endValue = _perfixValue - currentValue;
            break;
                               
        case cheng:
            endValue = _perfixValue * currentValue;
            break;
                               
        case chu:
            endValue = _perfixValue / currentValue;
            break;
                               
        default:
            break;
    }
    NSString * endStr = [NSString stringWithFormat:@"%.3f",endValue];//把相加的值转换为float类型
    [_label setText:endStr];//相加后的值赋给label
    _lastEnterType = YES;//等号后清零
                       
}
@end

CustomButton.h

#import <UIKit/UIKit.h>
@interface CustomButton : UIButton
- (id)initWithFrame:(CGRect)frame name:(NSString *)name;
@end

CustomButton.m

#import "CustomButton.h"
@implementation CustomButton
- (void)dealloc
{
    [super dealloc];
}
- (id)initWithFrame:(CGRect)frame name:(NSString *)name
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
        [self setTitle:name forState:UIControlStateNormal];
          
        [self setBackgroundColor:[UIColor whiteColor]];
        [self setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
        self.layer.borderWidth = 3;
        self.layer.borderColor=[UIColor greenColor].CGColor;
    }
    return self;
}
@end

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