1

I have a while loop that should be looping through a condition, but fails to go through the process more than once.

Here is my relevant code:

NSInteger i = 0;
    while(i <= building.departments.count)
    {
        NSLog(@"Number of building departments: %lu", (unsigned long)building.departments.count);
        NSLog(@"i : %ld", (long)i);

        UILabel *dtitleLB = [[UILabel alloc] initWithFrame:CGRectMake(5, y, 310, 20)];
        dtitleLB.text = ((DBDepartment*)[building.departments objectAtIndex:i]).Name;
        dtitleLB.textAlignment =  UITextAlignmentLeft;
        dtitleLB.backgroundColor = [UIColor clearColor];
        dtitleLB.textColor = [UIColor lightGrayColor];
        dtitleLB.font = [UIFont fontWithName:@"Helvetica" size:(16.0)];
        [scrollView addSubview:dtitleLB];
        y += 30;

        UIButton* dphoneNB = [UIButton buttonWithType:UIButtonTypeCustom];
        [dphoneNB setContentHorizontalAlignment:UIControlContentHorizontalAlignmentLeft];
        [dphoneNB setTitleColor:[UIColor colorWithRed:0.3 green:0.3 blue:0.9 alpha:1.0] forState:UIControlStateNormal];
        [dphoneNB addTarget:self action:@selector(numberPress:) forControlEvents:UIControlEventTouchUpInside];
        [dphoneNB setTitle:((DBDepartment*)[building.departments objectAtIndex:i]).Phone forState:UIControlStateNormal]; i++;
        dphoneNB.frame = CGRectMake(5, y, 315, 25);
        [scrollView addSubview:dphoneNB];
        y += 30;

        UIButton* dwebsiteNB = [UIButton buttonWithType:UIButtonTypeCustom];
        [dwebsiteNB setContentHorizontalAlignment:UIControlContentHorizontalAlignmentLeft];
        [dwebsiteNB setTitleColor:[UIColor colorWithRed:0.3 green:0.3 blue:0.9 alpha:1.0] forState:UIControlStateNormal];
        [dwebsiteNB addTarget:self action:@selector(linkPress:) forControlEvents:UIControlEventTouchUpInside];
        [dwebsiteNB setTitle:((DBDepartment*)[self->building.departments objectAtIndex:i - 1]).Website forState:UIControlStateNormal]; i++;
        dwebsiteNB.frame = CGRectMake(5, y, 315, 25);
        [scrollView addSubview:dwebsiteNB];
        y += 30;

        i++;
    }

The output for the first NSLog = 1 or greater depending on the user selection (never 0). The output for the second NSLog = 0 and never gets larger.

If you could go over my code and see if there are any obvious errors, that would be greatly appreciated.

Thanks!

4

1 回答 1

1

它不循环（或不规则循环）的原因是因为您增加i了不止一个点。请参阅下面的行（分解以更容易查看）。

...
        [dphoneNB setTitle:((DBDepartment*)[building.departments 
        objectAtIndex:i]).Phone forState:UIControlStateNormal]; i++;
...
        [dwebsiteNB setTitle:((DBDepartment*)[self->building.departments 
        objectAtIndex:i - 1]).Website forState:UIControlStateNormal]; i++;
...
        i++;

作为这样的循环的替代方案while，一个for循环就足够了。

于 2013-07-08T22:01:07.703 回答