iphone - 如何在 UIImagePickerViewController 中调用 Image 函数

Question

如何在 UIImagePickerviewcontroller 中调用此函数

- (UIImage*)imageByScalingAndCroppingForSize:(CGSize)targetSize
{
    UIImage *sourceImage = self;

    UIImage *newImage = nil;

    CGSize imageSize = sourceImage.size;

    CGFloat width = imageSize.width;

    CGFloat height = imageSize.height;

    CGFloat targetWidth = targetSize.width;

    CGFloat targetHeight = targetSize.height;

    CGFloat scaleFactor = 0.0;

    CGFloat scaledWidth = targetWidth;

    CGFloat scaledHeight = targetHeight;

    CGPoint thumbnailPoint = CGPointMake(0.0,0.0);

    if (CGSizeEqualToSize(imageSize, targetSize) == NO)
    {
        CGFloat widthFactor = targetWidth / width;

        CGFloat heightFactor = targetHeight / height;


        if (widthFactor > heightFactor)
        {
            scaleFactor = widthFactor; // scale to fit height
        }
        else
        {
            scaleFactor = heightFactor; // scale to fit width
        }

        scaledWidth  = width * scaleFactor;

        scaledHeight = height * scaleFactor;

        // center the image

        if (widthFactor > heightFactor)
        {
            thumbnailPoint.y = (targetHeight - scaledHeight) * 0.5;
        }
        else
        {
            if (widthFactor < heightFactor)
            {
                thumbnailPoint.x = (targetWidth - scaledWidth) * 0.5;
            }
        }
    }

    UIGraphicsBeginImageContext(targetSize); // this will crop

    CGRect thumbnailRect = CGRectZero;

    thumbnailRect.origin = thumbnailPoint;

    thumbnailRect.size.width  = scaledWidth;

    thumbnailRect.size.height = scaledHeight;

    [sourceImage drawInRect:thumbnailRect];

    newImage = UIGraphicsGetImageFromCurrentImageContext();

    if(newImage == nil)
    {
        NSLog(@"could not scale image");
    }

    //pop the context to get back to the default
    UIGraphicsEndImageContext();

    return newImage;
}



- (UIImage *)imageByCropping:(UIImage *)imageToCrop toRect:(CGRect)rect
  {
        CGImageRef imageRef = CGImageCreateWithImageInRect([imageToCrop CGImage], rect);

        UIImage *cropped = [UIImage imageWithCGImage:imageRef];

        CGImageRelease(imageRef);

         return cropped;

    } 

Answer 1

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{

   UIImage *img = [info objectForKey:UIImagePickerControllerEditedImage];
   img = [self imageByCropping:img toRect:CGRectMake(5, 5, 50, 80)]; // pass size as you need.

   /// Here you got cropped image 

   img = [self imageByScalingAndCroppingForSize:CGSizeMake(170, 180);] // pass size as you need;

   UIImageView *imgSetAlarmTime = [[UIImageView alloc] init];
   imgSetAlarmTime.frame = CGRectMake(10, 50, 100, 100); 
   [imgSetAlarmTime setImage: img];
   [self.view addSubview: imgSetAlarmTime];
}