Resize UIImage and change the size of UIImageView
This is the Swift equivalent for Rajneesh071's answer, using extensions
UIImage {
func scaleToSize(aSize :CGSize) -> UIImage {
if (CGSizeEqualToSize(self.size, aSize)) {
return self
}
UIGraphicsBeginImageContextWithOptions(aSize, false, 0.0)
self.drawInRect(CGRectMake(0.0, 0.0, aSize.width, aSize.height))
let image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return image
}
}
Usage:
let image = UIImage(named: "Icon")
item.icon = image?.scaleToSize(CGSize(width: 30.0, height: 30.0))
When you get the width and height of a resized image Get width of a resized image after UIViewContentModeScaleAspectFit, you can resize your imageView:
imageView.frame = CGRectMake(0, 0, resizedWidth, resizedHeight);
imageView.center = imageView.superview.center;
I haven't checked if it works, but I think all should be OK
- (UIImage *)image:(UIImage*)originalImage scaledToSize:(CGSize)size
{
//avoid redundant drawing
if (CGSizeEqualToSize(originalImage.size, size))
{
return originalImage;
}
//create drawing context
UIGraphicsBeginImageContextWithOptions(size, NO, 0.0f);
//draw
[originalImage drawInRect:CGRectMake(0.0f, 0.0f, size.width, size.height)];
//capture resultant image
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
//return image
return image;
}
Use the category below and then apply border from Quartz into your image:
[yourimage.layer setBorderColor:[[UIColor whiteColor] CGColor]];
[yourimage.layer setBorderWidth:2];
The category: UIImage+AutoScaleResize.h
#import <Foundation/Foundation.h>
@interface UIImage (AutoScaleResize)
- (UIImage *)imageByScalingAndCroppingForSize:(CGSize)targetSize;
@end
UIImage+AutoScaleResize.m
#import "UIImage+AutoScaleResize.h"
@implementation UIImage (AutoScaleResize)
- (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;
}
@end