Question

如果我的数据库中的某个字段等于一个数字，则应在我的视图中显示一定数量的图像。

例如如果字段“星级”等于3，则应显示3个图像（两个隐藏，3个可见）

当星级评分等于0时，以下代码有效，但出于某种原因，如果“星级”字段等于任何其他数字（例如3），则仍会显示所有5张图像？我错过了什么吗？

的.m

- (void)viewDidLoad {
    [super viewDidLoad];

    NSDictionary *neighbours = neighbourDetail;
    NSLog(@"This is neighbours detail info %@", neighbours);

    if ([[neighbourDetail objectForKey:@"star rating"] isEqual:@"0"]) {
        self.pawOne.hidden = YES;
        self.pawTwo.hidden = YES;
        self.pawThree.hidden = YES;
        self.pawFour.hidden = YES;
        self.pawFive.hidden = YES;

        if ([[neighbourDetail objectForKey:@"star rating"] isEqual:@"1"]) {
            self.pawOne.hidden = NO;
            self.pawTwo.hidden = YES;
            self.pawThree.hidden = YES;
            self.pawFour.hidden = YES;
            self.pawFive.hidden = YES;

            if ([[neighbourDetail objectForKey:@"star rating"] isEqual:@"2"]) {
                self.pawOne.hidden = NO;
                self.pawTwo.hidden = NO;
                self.pawThree.hidden = YES;
                self.pawFour.hidden = YES;
                self.pawFive.hidden = YES;

                if ([[neighbourDetail objectForKey:@"star rating"] isEqual:@"3"]) {
                    self.pawOne.hidden = NO;
                    self.pawTwo.hidden = NO;
                    self.pawThree.hidden = NO;
                    self.pawFour.hidden = YES;
                    self.pawFive.hidden = YES;

                    if ([[neighbourDetail objectForKey:@"star rating"] isEqual:@"4"]) {
                        self.pawOne.hidden = NO;
                        self.pawTwo.hidden = NO;
                        self.pawThree.hidden = NO;
                        self.pawFour.hidden = NO;
                        self.pawFive.hidden = YES;

                        if ([[neighbourDetail objectForKey:@"star rating"] isEqual:@"5"]) {
                            self.pawOne.hidden = NO;
                            self.pawTwo.hidden = NO;
                            self.pawThree.hidden = NO;
                            self.pawFour.hidden = NO;
                            self.pawFive.hidden = NO;
                        }
                    }
                }
            }
        }
    }
}

Answer 1

主要问题是if语句的嵌套不当。如果值不是@"0"，则永远不会检查任何其他值。

正确的格式是：

if (some condition 1) {
} else if (some condition 2) {
} else if (some condition 3) {
} else {
}

但是编写代码有一种更简单的方法：

- (void)viewDidLoad {
    [super viewDidLoad];

    NSDictionary *neighbours = neighbourDetail;
    int rating = [neighbourDetail[@"star rating"] intValue];
    self.pawOne.hidden = rating == 0;
    self.pawTwo.hidden = rating <= 1;
    self.pawThree.hidden = rating <= 2;
    self.pawFour.hidden = rating <= 3;
    self.pawFive.hidden = rating <= 4;
}

如果您的pawXXX观看次数不是数组，而是拥有5个不同的属性，那就更容易了。

Answer 2

你在前一个语句中都有if语句。

如果星级为＆＃34; 1＆＃34;，则执行第一个if语句的正文。然后，在if语句中，只有在星级评分为＆＃34; 2＆＃34;时才会执行下一个if语句。但是你已经确定它已经确定了＃＆＃34; 1＆＃34;。

如果您要使用一系列if语句，则需要关闭每个if语句，然后在此之后再使用单独的if语句。但是，对于这种情况，switch语句是更好的构造。将星级转换为nit并使用switch语句。

if语句没有显示结果？

2 个答案: