objective-c - 在xcode中滑动uislider时如何更新uiimage效果

Question

我想知道是否可以在滑动滑块时更新 aUIImage以UIImageView增加用于在图像中产生模糊效果的浮点值？到目前为止，我的滑块设置了一个浮点值，一个按钮根据浮点值产生模糊效果。任何代码都会很棒。

它看起来像这样：

float hello = [slider value];


    CIFilter *gaussianBlurFilter = [CIFilter filterWithName:@"CIGaussianBlur"];
    [gaussianBlurFilter setDefaults];
    [gaussianBlurFilter setValue:[CIImage imageWithCGImage:[imageView.image CGImage]] forKey:kCIInputImageKey];
    [gaussianBlurFilter setValue:@(hello) forKey:kCIInputRadiusKey];

    CIImage *outputImage = [gaussianBlurFilter outputImage];
    CIContext *context   = [CIContext contextWithOptions:nil];
    CGRect rect          = [outputImage extent];

    // these three lines ensure that the final image is the same size

    rect.origin.x        += (rect.size.width  - imageView.image.size.width ) / 2;
    rect.origin.y        += (rect.size.height - imageView.image.size.height) / 2;
    rect.size            = imageView.image.size;

    CGImageRef cgimg     = [context createCGImage:outputImage fromRect:rect];
    UIImage *image       = [UIImage imageWithCGImage:cgimg];
    CGImageRelease(cgimg);
    imageView.image =image;

任何代码将不胜感激：D