Simple calculator app crashes when a third number key is punched.
- by Justin
Hi , I am a newbie to the iphone app world. So I thought I try my luck with a calculator app.
Unfortunately I am running into an issue where if I press a third key in the calculator the app crashes. Sometimes I get this error EXC_BAD_ACCESS. Here is a code in my CalculatorViewController.m file.
#import "CalculatorViewController.h"
@implementation CalculatorViewController
@synthesize screenText;
- (IBAction)buttonPressed:(id)sender {
NSString *title = [sender titleForState:UIControlStateNormal];
[self collect:title];
}
- (void)collect:(NSString *)digitz {
NSString * newText = nil;
if ([digitz isEqualToString:@"+"]) {
[self add:result];
big_digit = nil;
}
else if ([digitz isEqualToString:@"+"]) {
[self sub:result];
}
else if ([digitz isEqualToString:@"x"]) {
[self multiply:result];
}
else if ([digitz isEqualToString:@"="]) {
[self equate:result];
}
else {
if (big_digit != nil && [big_digit isEqualToString:@"0"] == FALSE)
big_digit = [big_digit stringByAppendingFormat:@"%@",digitz];
else
big_digit = (NSMutableString *) digitz;
result = (int) big_digit;
newText = [[NSString alloc] initWithFormat:
@"%@",big_digit];
}
screenText.text = newText;
[newText release];
}
- (void)add:(int)res {
NSString * newText = nil;
ans = ans + res;
newText = [[NSString alloc] initWithFormat:
@"%@",ans];
screenText.text = newText;
[newText release];
}
Can anyone spot an obvious issue here. Here is the respective header file too.
#import <UIKit/UIKit.h>
@interface CalculatorViewController : UIViewController {
UILabel *screenText;
int number;
int result;
int ans;
//NSString *big_digit;
NSMutableString * big_digit ;
}
@property (nonatomic, retain) IBOutlet UILabel *screenText;
- (IBAction)buttonPressed:(id)sender;
- (void)collect:(NSString *)digitz;
- (void)add:(int)num;
- (void)sub:(int)num;
- (void)multiply:(int)num;
- (void)equate:(int)num;
@end
