iOS 7 :How to show images from photo album without strectch while placing it in uiimageview in larger size

Question

我的任务是从相册中获取图像并将其显示在一个 ViewController 中，其中有一个全屏 UIImageView。这里面临的问题是，当涉及到 UIImageView

时，显示相机拍摄的小尺寸照片会被拉伸(stretch)

我已尝试使用所有纵横比模式来保持图像正常。但没有运气

提前致谢!

Answer 1

如果你想从相册中选择相同尺寸的图片那么

self.photoImgView.contentMode=UIViewContentModeScaleAspectFit;// is best

self.photoImgView.contentMode=UIViewContentModeScaleAspectFill; //if you want to fill the large imageview size with selected photo

self.photoImgView.contentMode=UIViewContentModeScaleToFill; // if you want to fill the large imageview size with selected photo

否则您可以尝试使用以下解决方案在分配给 imageview 之前调整图像大小。

 UIImage *uiImage=[info valueForKey:@"UIImagePickerControllerOrignalImage"];//UIImagePickerControllerEditedImage

    CGSize size;
    NSData *imageData;

    imageData= UIImageJPEGRepresentation(uiImage, 1.0);


    UIImage *galleryImage=[self squareImageWithImage:[UIImage imageWithData:imageData] scaledToSize:CGSizeMake(320, 320)];

    photoImgView.image=galleryImage;

-(UIImage *)squareImageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize {
    double ratio;
    double delta;
    CGPoint offset;

    //make a new square size, that is the resized imaged width
    CGSize sz = CGSizeMake(newSize.width, newSize.width);

    //figure out if the picture is landscape or portrait, then
    //calculate scale factor and offset
    if (image.size.width > image.size.height) {
        ratio = newSize.width / image.size.width;
        delta = (ratio*image.size.width - ratio*image.size.height);
        offset = CGPointMake(delta/2, 0);
    } else {
        ratio = newSize.width / image.size.height;
        delta = (ratio*image.size.height - ratio*image.size.width);
        offset = CGPointMake(0, delta/2);
    }

    //make the final clipping rect based on the calculated values
    CGRect clipRect = CGRectMake(-offset.x, -offset.y,
                                 (ratio * image.size.width) + delta,
                                 (ratio * image.size.height) + delta);


    //start a new context, with scale factor 0.0 so retina displays get
    //high quality image
    if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) {
        UIGraphicsBeginImageContextWithOptions(sz, YES, 0.0);
    } else {
        UIGraphicsBeginImageContext(sz);
    }
    UIRectClip(clipRect);
    [image drawInRect:clipRect];
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return newImage;
}

希望对你有帮助