可以连续运算，有小数点、百分号。
AppDelegate.h
#import <UIKit/UIKit.h>
@interface AppDelegate : UIResponder <UIApplicationDelegate>
{
UILabel*_label;
}
@property (strong, nonatomic) UIWindow *window;
//存储操作符
@property(assign,nonatomic)int oper;
//存储第一个操作数
@property(assign,nonatomic)float one;
//判断小数点
@property(assign,nonatomic)BOOL point;
//判断连续运算
@property(assign,nonatomic)BOOL con;
//是否刚按过等于号
@property(assign,nonatomic)BOOL equal;
@end
//
// AppDelegate.m
//
#import "AppDelegate.h"
@implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];
UIView *view=[[UIView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
[self.window makeKeyAndVisible];
[self.window addSubview:view];
//结果输出label
_label=[[UILabel alloc]initWithFrame:CGRectMake(20, 30, 280, 55)];
_label.textColor=[UIColor whiteColor];
_label.textAlignment=NSTextAlignmentRight;
_label.backgroundColor=[UIColor blackColor];
_label.font=[UIFont systemFontOfSize:30];
_label.text=@"0";
[view addSubview:_label];
[_label release];
//循环产生除了最后一行的button
int x=20;
int y=95;
for (int i=0; i<16; i++) {
UIButton*button=[UIButton buttonWithType:UIButtonTypeCustom];
button.frame=CGRectMake(x, y, 55, 55);
NSString*picName=[NSString stringWithFormat:@"%d",i];
[button setImage:[UIImage imageNamed:picName] forState:UIControlStateNormal];
button.tag=i+1001;
// button.backgroundColor=[UIColor cyanColor];
[button addTarget:self action:@selector(click:) forControlEvents:UIControlEventTouchUpInside];
[view addSubview:button];
x=x+75;
if ((i+1)%4==0) {
y=y+75;
}
if(x>=320)x=20;
}
//最后一行
//0按键
UIButton*button0=[UIButton buttonWithType:UIButtonTypeCustom];
button0.frame=CGRectMake(20, 395, 130, 55);
[button0 setImage:[UIImage imageNamed:@"0_btn_highlighted"] forState:UIControlStateNormal];
[button0 addTarget:self action:@selector(click:) forControlEvents:UIControlEventTouchUpInside];
button0.tag=1017;
[view addSubview:button0];
//点按键
UIButton*buttonPoint=[UIButton buttonWithType:UIButtonTypeCustom];
buttonPoint.frame=CGRectMake(170, 395, 55, 55);
[buttonPoint setImage:[UIImage imageNamed:@"dian_btn_highlighted"] forState:UIControlStateNormal];
buttonPoint.tag=1018;
[buttonPoint addTarget:self action:@selector(click:) forControlEvents:UIControlEventTouchUpInside];
[view addSubview:buttonPoint];
//等号
UIButton*buttonDeng=[UIButton buttonWithType:UIButtonTypeCustom];
buttonDeng.frame=CGRectMake(245, 395, 55, 55);
[buttonDeng setImage:[UIImage imageNamed:@"dengyu_btn_highlighted"] forState:UIControlStateNormal];
buttonDeng.tag=1019;
[buttonDeng addTarget:self action:@selector(click:) forControlEvents:UIControlEventTouchUpInside];
[view addSubview:buttonDeng];
return YES;
}
//功能实现
-(void)click:(UIButton*)button{
int tag=button.tag;
NSMutableString*temp=[[NSMutableString alloc]init] ;
//非数字键
if (tag==1001||tag==1002||tag==1003||tag==1004||tag==1008||tag==1012||tag==1016) {
switch (tag) {
case 1004:{
//判断是不是连续运算
if (_oper!=0) {
_con=YES;
switch (self.oper) {
case 1:
_one=_one+[_label.text floatValue];
break;
case 2:
_one=_one-[_label.text floatValue];
break;
case 3:
_one=_one*[_label.text floatValue];
break;
case 4:
_one=_one/[_label.text floatValue]; break;
}
temp=[NSMutableString stringWithFormat:@"%g",_one];
}
//存储本次操作符
_oper=4;
break;
}
//乘号
case 1008:
if (_oper!=0) {
_con=YES;
switch (self.oper) {
case 1:
_one=_one+[_label.text floatValue];
break;
case 2:
_one=_one-[_label.text floatValue];
break;
case 3:
_one=_one*[_label.text floatValue];
break;
case 4:
_one=_one/[_label.text floatValue]; break;
}
temp=[NSMutableString stringWithFormat:@"%g",_one];
}
_oper=3;
break;
//加号
case 1012:{
if (_oper!=0) {
_con=YES;
switch (self.oper) {
case 1:
_one=_one+[_label.text floatValue];
break;
case 2:
_one=_one-[_label.text floatValue];
break;
case 3:
_one=_one*[_label.text floatValue];
break;
case 4:
_one=_one/[_label.text floatValue]; break;
}
temp=[NSMutableString stringWithFormat:@"%g",_one];
}
_oper=1;
break;
}
//减号
case 1016:
if (_oper!=0) {
_con=YES;
switch (self.oper) {
case 1:
_one=_one+[_label.text floatValue];
break;
case 2:
_one=_one-[_label.text floatValue];
break;
case 3:
_one=_one*[_label.text floatValue];
break;
case 4:
_one=_one/[_label.text floatValue]; break;
}
temp=[NSMutableString stringWithFormat:@"%g",_one];
}
_oper=2;
break;
//清除按键
case 1001:
_oper=0;
temp=[NSMutableString stringWithString:@"0"];
break;
case 1002:
temp=[NSMutableString stringWithFormat:@"%g",-[_label.text floatValue]];
break;
case 1003:
temp=[NSMutableString stringWithFormat:@"%g",[_label.text floatValue]/100];
break;
default:
break;
}
_point=NO;
_one=[_label.text floatValue];
[_label setText:temp];
}
//等号
else if (tag==1019) {
float two=[_label.text floatValue];
float result = 0;
switch (self.oper) {
case 1:
result=self.one+two;
break;
case 2:
result=self.one-two;
break;
case 3:
result=self.one*two;
break;
case 4:
result=self.one/two;
break;
}
_equal=YES;
_point=NO;
_oper=0;
temp=[NSMutableString stringWithFormat:@"%g",result];
[_label setText:temp];
}//=
//按下小数点
else if (tag==1018) {
if (_point) {
}
else {
if ([_label.text floatValue]==0) {
[temp appendString:@"0."];
_point=YES;
}
else{
[temp setString:_label.text];
[temp appendString:@"."];
_point=YES;
}
[_label setText:temp];
}
}
//数字键
else{
int number;
switch (tag) {
case 1005://7
number=7;
break;
case 1006://8
number=8;
break;
case 1007://9
number=9;
break;
case 1009://4
number=4;
break;
case 1010://5
number=5;
break;
case 1011://6
number=6;
break;
case 1013://1
number=1;
break;
case 1014://2
number=2;
break;
case 1015://3
number=3;
break;
case 1017://0
number=0;
break;
default:
break;
}
if (_label.text!=nil&&number!=0) {
[temp setString:_label.text];
}
if ([_label.text floatValue]!=0&&number==0) {
[temp setString:_label.text];
}
if ([_label.text floatValue]==0&&number!=0&&[_label.text length]==1) {
temp=[NSMutableString stringWithString:@""];
}
if (_con) {
_one=[_label.text floatValue];
temp=[NSMutableString stringWithString:@""];
_con=NO;
}
if (_equal) {
temp=[NSMutableString stringWithString:@""];
_equal=NO;
}
[temp appendString:[NSString stringWithFormat:@"%d",number]];
[_label setText:temp];
}
}
- (void)applicationWillResignActive:(UIApplication *)application
{
// Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
// Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
}
- (void)applicationDidEnterBackground:(UIApplication *)application
{
// Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
// If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
}
- (void)applicationWillEnterForeground:(UIApplication *)application
{
// Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
}
- (void)applicationDidBecomeActive:(UIApplication *)application
{
// Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
}
- (void)applicationWillTerminate:(UIApplication *)application
{
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
}
@end
效果图：
