如何检测UIImageView的宽度和高度

Question

I'm looking to detect the width and height of an image and pass those dimensions into the following code:

   UIImageView *imgView=[[UIImageView alloc] initWithFrame:CGRectMake(25, 5, imgView.size.width, imgView.size.width)];

Either there's something wrong with my syntax or this the wrong way to go about doing this. Any help would be great, thanks

Answer 1

Do:

UIImage *someImage = [UIImage imageNamed:@"someImage.png"];
UIImageView *someImageView = [[UIImageView alloc] initWithImage:someImage];
someImageView.frame = CGRectMake(0, 0, someImage.size.width, someImage.size.height);

Answer 2

Try this

UIImage *image = [UIImage imageNamed:@"image.png"];
UIImageView *imgView = [[UIImageView alloc] initWithImage:image];
imgView.frame = CGRectMake(0, 0, image.size.width, image.size.height);

Hope it helps you

Answer 3

You can grab the size of an image from the UIImage size property. Maybe something like:

UIImage *img = [UIImage imageNamed:@"image.png"];
UIImageView *imgView=[[UIImageView alloc] initWithFrame:CGRectMake(25, 5, img.size.width, img.size.width)];

Or you can just:

UIImageView *imgView=[[UIImageView alloc] initWithImage:img];

and it'll be sized automatically.

Answer 4

I suspect there is no width or height for the image view as you've just alloced and initialised it. The initWithFrame initialisation methods requires a float value, so you can't query imgView to return a value for the width and height yet as its yet to be determined.

I usually would use the initialiser initWithImage. Then modify the width and height of the imageview after initialisation.

Answer 5

if you Want to set Maximum Width or Height then try this Code. it will control the size as well as you can set frame of image view dynamically.

CGSize size = image.size;

// Here Maximum width of image is 220 

    if (size.width > 220)
    {
        size.height /= (size.width / 220);
        size.width = 220;
    }
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, size.width, size.height)];
imageView.image = image;

// For layer mask or round corner

imageView.layer.cornerRadius = 5.0;
imageView.layer.masksToBounds = YES;