iOS 向数组添加动态值

Question

我想在 for 循环中初始化的数组中添加 UIImage 的动态值，所以我创建了一个 NSMutableArray 来首先在 for 循环中设置对象，然后尝试从中检索值. 请您看看我哪里出错了，以及添加动态值时最好的方法是什么。

NSMutableDictionary * dic= [[NSMutableDictionary alloc]init];
NSMutableArray *cImages = [[NSMutableArray alloc]init];

for(int i=0; i<5; i++) {
    NSString * imageKey= [NSString stringWithFormat:@"image%i",i+1];              

    NSData *imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString: [[results objectAtIndex:i]valueForKey:imageKey]]];
    UIImage *imageOne = [UIImage imageWithData:imageData];
    [dic setObject:imageOne forKey:imageKey];

}

for (NSString *key in dic) {
    NSString *sprite = [dic objectForKey:key];
    //adding below to the array
    [cImages addObject:sprite];             
}

Answer 1

将 UIImage 添加到可变数组有什么问题？

NSMutableArray *cImages = [[NSMutableArray alloc]init];

for(int i = 0; i < 5; i++)
{
    NSString *imageKey= [NSString stringWithFormat:@"image%i", i+1];
    UIImage *imageToAdd = [UIImage imageNamed:imageKey];
    [cImages addObject:imageToAdd];
}

// Using the images
for (UIImage *image in cImages)
{
    // Do whatever u want with each image.
}

如果您确实需要使用字典来通过名称 "image1, image2" 等访问 UIImage，您可以这样做：

NSDictionary *dict = [[NSDictionary alloc] init];
for (int i = 0; i < 5; i++)
{
    NSString *imageKey = [NSString stringWithFormat:@"image%i", i+1];
    UIImage *image = [UIImage imageNamed:@"nameOfImageFile.png"];
    [dict setObject:image forKey:imageKey];
}

// Now you can access the UIImage values by their names (image1,image2,image3,image4,image5)
UIImage *imageToUse = [dict valueForKey:@"image1"];

（还没有测试这些，但它是相当标准的）。

iOS 向数组添加动态值

iOS Adding Dynamic Values to Array

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