UIImageView 中的 UIViewContentModeScaleAspectFit 无法正常工作

Question

I try to fit an Image into my UIImageView which is called imgBack I define my UIImageView in the header as IBOutlet

IBOutlet UIImageView *imgBack;

in my viewDidLoad function I set the contentMode like this:

imgBack.contentMode = UIViewContentModeScaleAspectFit;

But after I load an image into imgBack like this:

imgBack.image = [UIImage imageWithContentsOfFile: imagePath];

it does not scale to fit into the imageview

This is the picture I load into imgBack: image i try to load

And this is how it looks like in the view: image in UIImageView

As you see, the image does not fit into the View. Does anyone know why?

Answer 1

If changing ImageView contentMode does not work for you, then you can try to resize the image to fit in Image View with help of following code

UIImage *originalImage = [UIImage imageWithContentsOfFile: imagePath];
imgBack.image = [self resizeImage: originalImage imageSize: imgBack.size];

and add this code to your ViewController

-(UIImage*)resizeImage:(UIImage *)image imageSize:(CGSize)size
    {
        UIGraphicsBeginImageContext(size);
        [image drawInRect:CGRectMake(0,0,size.width,size.height)];
        UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
        //here is the scaled image which has been changed to the size specified
        UIGraphicsEndImageContext();
        return newImage;

    }

Answer 2

Attach the image to UIImageView first and then change the content mode

imgBack.image = [UIImage imageWithContentsOfFile: imagePath];
imgBack.contentMode = UIViewContentModeScaleAspectFill;
imgBack.clipsToBounds = YES;

Answer 3

below are the mode try and check
UIViewContentModeScaleToFill,
    UIViewContentModeScaleAspectFit,      // contents scaled to fit with fixed aspect. remainder is transparent
    UIViewContentModeScaleAspectFill,     // contents scaled to fill with fixed aspect. some portion of content may be clipped.
    UIViewContentModeRedraw,              // redraw on bounds change (calls -setNeedsDisplay)
    UIViewContentModeCenter,              // contents remain same size. positioned adjusted.
    UIViewContentModeTop,
    UIViewContentModeBottom,
    UIViewContentModeLeft,
    UIViewContentModeRight,
    UIViewContentModeTopLeft,
    UIViewContentModeTopRight,
    UIViewContentModeBottomLeft,
    UIViewContentModeBottomRight,