iPhone에서 컬러 1x1 UIImage를 동적으로 만드는 방법은 무엇입니까?

iPhone에서 컬러 1x1 UIImage를 동적으로 만드는 방법은 무엇입니까?

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UIColor를 기반으로 1x1 UIImage를 동적으로 만들고 싶습니다.

나는 이것이 Quartz2d로 빨리 이루어질 수 있다고 생각하며, 기초를 파악하려는 문서를 숙고하고 있습니다. 그러나 많은 잠재적 인 함정이있는 것 같습니다. 사물 당 비트 및 바이트 수를 올바르게 식별하지 않고 올바른 플래그를 지정하지 않고 사용하지 않는 데이터를 해제하지 않는 등

Quartz 2d (또는 다른 간단한 방법)로 어떻게 이것을 안전하게 수행 할 수 있습니까?

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당신은 사용할 수 있습니다 CGContextSetFillColorWithColor및 CGContextFillRect이에 대한 :

빠른

extension UIImage {
    class func image(with color: UIColor) -> UIImage {
        let rect = CGRectMake(0.0, 0.0, 1.0, 1.0)
        UIGraphicsBeginImageContext(rect.size)
        let context = UIGraphicsGetCurrentContext()

        CGContextSetFillColorWithColor(context, color.CGColor)
        CGContextFillRect(context, rect)

        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return image
    }
}

스위프트 3

extension UIImage {
    class func image(with color: UIColor) -> UIImage {
        let rect = CGRect(origin: CGPoint(x: 0, y:0), size: CGSize(width: 1, height: 1))
        UIGraphicsBeginImageContext(rect.size)
        let context = UIGraphicsGetCurrentContext()!

        context.setFillColor(color.cgColor)
        context.fill(rect)

        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return image!
    }
}

목표 -C

+ (UIImage *)imageWithColor:(UIColor *)color {
    CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();

    CGContextSetFillColorWithColor(context, [color CGColor]);
    CGContextFillRect(context, rect);

    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return image;
}

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Matt Stephen의 코드를 기반으로 한 또 다른 옵션이 있습니다. 크기를 조정할 수있는 단색 이미지를 만들어 재사용하거나 크기를 변경할 수 있습니다 (예 : 배경에 사용).

+ (UIImage *)prefix_resizeableImageWithColor:(UIColor *)color {
    CGRect rect = CGRectMake(0.0f, 0.0f, 3.0f, 3.0f);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();

    CGContextSetFillColorWithColor(context, [color CGColor]);
    CGContextFillRect(context, rect);

    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    image = [image resizableImageWithCapInsets:UIEdgeInsetsMake(1, 1, 1, 1)];

    return image;
}

UIImage 카테고리에 넣고 접 두부를 변경하십시오.

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I used Matt Steven's answer many times so made a category for it:

@interface UIImage (mxcl)
+ (UIImage *)squareImageWithColor:(UIColor *)color dimension:(int)dimension;
@end

@implementation UIImage (mxcl)
+ (UIImage *)squareImageWithColor:(UIColor *)color dimension:(int)dimension {
    CGRect rect = CGRectMake(0, 0, dimension, dimension);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();

    CGContextSetFillColorWithColor(context, [color CGColor]);
    CGContextFillRect(context, rect);

    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return image;
}
@end

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Using Apple's latest UIGraphicsImageRenderer the code is pretty small:

import UIKit

extension UIImage {
    static func from(color: UIColor) -> UIImage {
        let size = CGSize(width: 1, height: 1)
        return UIGraphicsImageRenderer(size: size).image(actions: { (context) in
            context.cgContext.setFillColor(color.cgColor)
            context.fill(.init(origin: .zero, size: size))
        })
    }
}

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To me, a convenience init feels neater in Swift.

extension UIImage {

    convenience init?(color: UIColor, size: CGSize = CGSize(width: 1, height: 1)) {

        let rect = CGRect(x: 0, y: 0, width: size.width, height: size.height)
        UIGraphicsBeginImageContext(rect.size)
        guard let context = UIGraphicsGetCurrentContext() else {
            return nil
        }

        context.setFillColor(color.cgColor)
        context.fill(rect)

        guard let image = context.makeImage() else {
            return nil
        }
        UIGraphicsEndImageContext()

        self.init(cgImage: image)
    }

}

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Ok, this won't be exactly what you want, but this code will draw a line. You can adapt it to make a point. Or at least get a little info from it.

Making the image 1x1 seems a little weird. Strokes ride the line, so a stroke of width 1.0 at 0.5 should work. Just play around.

- (void)drawLine{

UIGraphicsBeginImageContext(CGSizeMake(320,300));

CGContextRef ctx = UIGraphicsGetCurrentContext();

float x = 0;
float xEnd = 320;
float y = 300;

CGContextClearRect(ctx, CGRectMake(5, 45, 320, 300));

CGContextSetGrayStrokeColor(ctx, 1.0, 1.0);

CGContextSetLineWidth(ctx, 1);
CGPoint line[2] = { CGPointMake(x,y), CGPointMake(xEnd, y) };

CGContextStrokeLineSegments(ctx, line, 2);

UIImage *theImage=UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
}

참고URL : https://stackoverflow.com/questions/990976/how-to-create-a-colored-1x1-uiimage-on-the-iphone-dynamically