Question

I am using UIViewContentModeScaleToFill to scale image.After scaling,Image is not showing on correct position.Help me.

Below is my code:

  UIImage *image=[UIImage imageNamed:@"image2.png"];
    UIImageView *imageView = [[UIImageView alloc] initWithImage:image]; 
    imageView.frame=CGRectMake(0, 0, 200, 200);
    imageView.contentMode = UIViewContentModeScaleAspectFit;

    //change width of frame
    CGRect frame = imageView.frame;
    imageView.frame = frame;
    [self.view addSubview:imageView];

After scaling:

refer to image 1

Before scaling:

refer to image 2

I want scaling image starting from origin point (0,0).

Answer 1

Hi try the below code i hope it help you to get idea….

 UIImage *image=[UIImage imageNamed:@"image2.png"];
    UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
  //  imageView.contentMode = UIViewContentModeScaleToFill;
    imageView.contentMode = UIViewContentModeScaleAspectFit; 
    imageView.frame = self.view.bounds;
    [self.view addSubview:imageView];

Update after below comment:

I want to crop the image without changing its aspect ration.the width
is 200px.and height will change according to width. – shivam

you want to crop means you try the below category code:

UIImage+MyImage.h

#import <UIKit/UIKit.h>

@interface UIImage (MyImage)


+ (UIImage*)imageFromView:(UIView*)view;
+ (UIImage*)imageFromView:(UIView*)view scaledToSize:(CGSize)newSize;
+ (UIImage*)imageWithImage:(UIImage*)image scaledToSize:(CGSize)newSize;
+ (void)beginImageContextWithSize:(CGSize)size;
+ (UIImage *)croppedImage:(UIImage *)myImage :(CGRect)bounds;

+ (UIImage *) imageFromColor:(UIColor *)color;

@end

UIImage+MyImage.m

#import "UIImage+MyImage.h"

@implementation UIImage (MyImage)

+ (void)beginImageContextWithSize:(CGSize)size
{
    if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) {
        if ([[UIScreen mainScreen] scale] == 2.0) {
            UIGraphicsBeginImageContextWithOptions(size, YES, 2.0);
        } else {
            UIGraphicsBeginImageContext(size);
        }
    } else {
        UIGraphicsBeginImageContext(size);
    }
}

+ (void)endImageContext
{
    UIGraphicsEndImageContext();
}

+ (UIImage*)imageFromView:(UIView*)view
{
    [self beginImageContextWithSize:[view bounds].size];
    BOOL hidden = [view isHidden];
    [view setHidden:NO];
    [[view layer] renderInContext:UIGraphicsGetCurrentContext()];
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    [self endImageContext];
    [view setHidden:hidden];
    return image;
}

+ (UIImage*)imageFromView:(UIView*)view scaledToSize:(CGSize)newSize
{
    UIImage *image = [self imageFromView:view];
    if ([view bounds].size.width != newSize.width ||
        [view bounds].size.height != newSize.height) {
        image = [self imageWithImage:image scaledToSize:newSize];
    }
    return image;
}

+ (UIImage*)imageWithImage:(UIImage*)image scaledToSize:(CGSize)newSize
{
    [self beginImageContextWithSize:newSize];
    [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    [self endImageContext];
    return newImage;
}


+ (UIImage *)croppedImage:(UIImage *)myImage :(CGRect)bounds {
    CGImageRef imageRef = CGImageCreateWithImageInRect(myImage.CGImage, bounds);
    UIImage *croppedImage = [UIImage imageWithCGImage:imageRef];
    CGImageRelease(imageRef);
    CGSize asd =  croppedImage.size;
    return croppedImage;
}





+ (UIImage *) imageFromColor:(UIColor *)color {
    CGRect rect = CGRectMake(0, 0, 1, 1);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetFillColorWithColor(context, [color CGColor]);
    //  [[UIColor colorWithRed:222./255 green:227./255 blue: 229./255 alpha:1] CGColor]) ;
    CGContextFillRect(context, rect);
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return img;
}




@end

the call will be :

imageView.image=[UIImage croppedImage:imageView.Image :CGRectMake(0,0,200,200) ];