ios：colorWithPatternImage，全屏拉伸圖像

Question

我有一個視圖，並希望通過UIImage為此視圖設置backGroudColor。 代碼如下：

self.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"backImage.png"]];

問題是：backImage'frame比視圖小。 如何將UIImage拉伸到我的視野。 我知道使用UIImageView可以達到。

有人有好主意嗎？

更新：

我無法上傳一張圖片。

像這樣：backImge的大小是30 * 30，我的視圖大小是1024 * 700，當我使用myview.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"backImage.png"]];

結果是myview的backGroup有很多'backImage.png'。 我的目標是讓一個'backImage.png'充滿我的觀點。

Answer 1

試試。

self.layer.contents = (id)[UIImage imageNamed:@"freshBackground.png"].CGImage;

迅速：

self.view.layer.contents = UIImage(named: "freshBackground")!.cgImage

Answer 2

據我所知，你無法直接調整背景的圖案圖像。 最簡單的方法是更改​​圖像以適合父視圖的幀大小。 或者，您可以重繪圖像以適合父視圖的大小。

UIView * yourView = [[UIView alloc] initWithFrame:CGRectMake(10.f, 100.f, 300.f, 100.f)];
UIImage * targetImage = [UIImage imageNamed:@"backImage.png"];

// redraw the image to fit |yourView|'s size
UIGraphicsBeginImageContextWithOptions(yourView.frame.size, NO, 0.f);
[targetImage drawInRect:CGRectMake(0.f, 0.f, yourView.frame.size.width, yourView.frame.size.height)];
UIImage * resultImage = UIGraphicsGetImageFromCurrentImageContext();    
UIGraphicsEndImageContext();

[yourView setBackgroundColor:[UIColor colorWithPatternImage:resultImage]];

Answer 3

world000的答案翻譯成Swift：

self.layer.contents = UIImage(named: "freshBackground.png")?.CGImage

Answer 4

根據Kjuly的回答，如果您希望圖像在中心正確插入而不是被拉伸，請使用此方法獲取新圖像：

#pragma mark - Image
+(UIImage*)imageFitInCenterForSize:(CGSize)inSize forSourceImage:(UIImage*)inImage
{
    // redraw the image to fit |yourView|'s size
    CGSize imageOriginalSize = inImage.size;
    UIImage *resultImage = nil;
    if (imageOriginalSize.width<=inSize.width && imageOriginalSize.height<=inSize.height)
    {
        UIGraphicsBeginImageContextWithOptions(inSize, NO, 0.f);
        [inImage drawInRect:CGRectMake((inSize.width-imageOriginalSize.width)/2.0, (inSize.height-imageOriginalSize.height)/2.0, imageOriginalSize.width, imageOriginalSize.height)];
        resultImage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
    }
    return resultImage;
}

與重載變體相同：

+(UIImage*)imageFitInCenterForSize:(CGSize)inSize forSourceImage:(UIImage*)inImage xOffset:(CGFloat)inXOffset yOffset:(CGFloat)inYOffset
{
    // http://stackoverflow.com/questions/10629403/ios-colorwithpatternimage-stretch-image-full-screen
    // redraw the image to fit |yourView|'s size
    CGSize imageOriginalSize = inImage.size;
    UIImage *resultImage = nil;
    if (imageOriginalSize.width<=inSize.width && imageOriginalSize.height<=inSize.height)
    {
        UIGraphicsBeginImageContextWithOptions(inSize, NO, 0.f);
        [inImage drawInRect:CGRectMake((inSize.width-imageOriginalSize.width)/2.0+inXOffset, (inSize.height-imageOriginalSize.height)/2.0+inYOffset, imageOriginalSize.width, imageOriginalSize.height)];
        resultImage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
    }
    return resultImage;
}

Answer 5

我使用以下方法：

1. 在特定邊界內繪制圖像（這使其縮放）
2. 使用生成的圖像作為模式。

碼：

UIGraphicsBeginImageContext(self.window.frame.size);
[[UIImage imageNamed:@"background"] drawInRect:self.window.bounds];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.window.backgroundColor = [UIColor colorWithPatternImage:image];

Answer 6

這是基於之前的評論，一個版本首先縮放圖像，然后裁剪成比例填充。

func imageScaledToFillSize(size: CGSize, image: UIImage) -> UIImage
{
    let aspect = image.size.width / image.size.height;
    UIGraphicsBeginImageContextWithOptions(size, false, 0)
    if (size.width / aspect <= size.height) {
        let resizedImg = self.imageScaledToSize(CGSize(width: size.height * aspect, height: size.height), image: image)
        resizedImg.drawInRect(CGRectMake((size.width - resizedImg.size.width)/2, 0, resizedImg.size.width, resizedImg.size.height))
    } else {
        let resizedImg = self.imageScaledToSize(CGSize(width: size.width, height: size.width / aspect), image: image)
        resizedImg.drawInRect(CGRectMake(0, (size.height-resizedImg.size.height)/2, resizedImg.size.width, resizedImg.size.height))
    }
    let imageR = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return imageR;
}

func imageScaledToSize(size: CGSize, image: UIImage) -> UIImage {
    UIGraphicsBeginImageContextWithOptions(size, false, 0.0);
    image.drawInRect(CGRectMake(0.0, 0.0, size.width, size.height))
    let imageR = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext();
    return imageR;
}