first ios app

calculatorViewController.m

 1 #import "CalculatorViewController.h"
 2 #import "CalculatorBrain.h"
 3 
 4 @interface CalculatorViewController ()//create private varible
 5 @property (nonatomic) BOOL useIsInTheMiddleOfEnteringANumber;
 6 
 7 @property (nonatomic, strong) CalculatorBrain *brain;
 8 @end
 9 
10 @implementation CalculatorViewController
11 
12 @synthesize display = _display;
13 @synthesize useIsInTheMiddleOfEnteringANumber = _useIsInTheMiddleOfEnteringANumber;
14 @synthesize brain = _brain;
15 
16 - (CalculatorBrain *)brain  //setter
17 {
18     if(!_brain) _brain = [[CalculatorBrain alloc] init];
19     return _brain;
20 }
21 
22 
23 - (IBAction)digitPressed:(UIButton *)sender
24 {
25     NSString *digit = sender.currentTitle;
26     if(self.useIsInTheMiddleOfEnteringANumber) {
27         self.display.text = [self.display.text stringByAppendingString:digit]; 
28     } else {
29         self.display.text = digit;
30         self.useIsInTheMiddleOfEnteringANumber = YES;
31     }
32     
33     
34 /*
35     UILabel *myDisplay = self.display;  //[self display];  getter
36     NSString *CurrentText = [myDisplay text];
37     NSString *newText = [CurrentText stringByAppendingString:digit];
38     myDisplay.text = newText;//[myDisplay setText:newText]; setter
39     */
40 
41     
42     
43 }
44 
45 - (IBAction)doublePressed:(UIButton *)sender {
46     
47     double result = [self.brain performOperation:sender.currentTitle];
48     NSString *resultString = [NSString stringWithFormat:@"%g", result];
49     self.display.text = resultString;
50 }
51 
52 - (IBAction)operationPressed:(UIButton *)sender 
53 {
54     
55     if(self.useIsInTheMiddleOfEnteringANumber) [self enterPressed];
56     double result = [self.brain performOperation:sender.currentTitle];
57     NSString *resultString = [NSString stringWithFormat:@"%g", result];
58     self.display.text = resultString;
59     
60 }
61 
62 - (IBAction)enterPressed
63 {
64     [self.brain pushOperand:[self.display.text doubleValue]];
65     self.useIsInTheMiddleOfEnteringANumber = NO;
66 }
67 
68 
69 @end

viewController.h

 

1 #import <UIKit/UIKit.h>
2 
3 @interface CalculatorViewController : UIViewController
4 
5 @property (weak, nonatomic) IBOutlet UILabel *display;
6 
7 @end

 

Brain.h

 1 #import <Foundation/Foundation.h>
 2 
 3 @interface CalculatorBrain : NSObject// model
 4 
 5 
 6 - (void)pushOperand: (double)operand;
 7 
 8 - (double) performOperation:(NSString *)operation;
 9 
10 @end

Brain.m

 1 #import "CalculatorBrain.h"
 2 @interface CalculatorBrain()
 3 @property (nonatomic, strong) NSMutableArray *operandStack;
 4 @end
 5 
 6 
 7 @implementation CalculatorBrain
 8 
 9 
10 @synthesize operandStack = _operandStack;
11 
12 - (NSMutableArray *)operandStack//getter
13 {
14     if(_operandStack == nil) _operandStack = [[NSMutableArray alloc] init];
15     return _operandStack;
16 }
17 
18 
19 - (void)pushOperand: (double)operand
20 {
21    
22     [self.operandStack addObject:[NSNumber numberWithDouble:operand]];//must add double
23     
24 }
25 
26 - (double) popOperand
27 {
28     NSNumber *operandObject = [self.operandStack lastObject];
29     if(operandObject != nil) [self.operandStack removeLastObject];
30     return [operandObject doubleValue];
31 }
32 
33 - (double) performOperation:(NSString *)operation
34 {
35     double result = 0;
36     if([operation isEqualToString:@"+"]) {
37         result = [self popOperand] + [self popOperand];
38     } else if ([@"*" isEqualToString:operation]) {
39         result = [self popOperand] * [self popOperand];
40     } else if ([@"^" isEqualToString:operation]) {
41         double d = [self popOperand];
42         result =  d * d;
43     }
44     [self pushOperand:result];
45     return result;
46 }
47 
48 @end

 

 

screen 

posted @ 2012-09-15 17:01  Matrix54  阅读(222)  评论(0)  编辑  收藏  举报