如何添加视觉效果视图模糊所有视图故事板iOS？
我需要添加visual effect视图与中心activityindicator与loading标签为所有设备fullscreen使用objective C 我正在使用storyboard下面张贴的图片我不能添加视觉效果模糊视图在所有顶部。
你可以尝试下面的代码来添加模糊效果：
// Usage [loginView blurBackgroundWithScreenshotView:backgroundImageView withType:BlurSubView withColor:BlurBlackView withPoint:CGPointZero]; // // UIImage+Blur.h // // Created by Ankit Thakur on 07/03/14. // #import <UIKit/UIKit.h> @interface UIImage (Blur) - (UIImage*) blurredSnapshot; @end // // UIImage+Blur.m // // Created by Ankit Thakur on 07/03/14. // #import "UIImage+Blur.h" #import <Accelerate/Accelerate.h> @implementation UIImage (Blur) - (UIImage *)applyBlurWithRadius:(CGFloat)blurRadius tintColor:(UIColor *)tintColor saturationDeltaFactor:(CGFloat)saturationDeltaFactor maskImage:(UIImage *)maskImage { // Check pre-conditions. if (self.size.width < 1 || self.size.height < 1) { NSLog (@"*** error: invalid size: (%.2f x %.2f). Both dimensions must be >= 1: %@", self.size.width, self.size.height, self); return nil; } if (!self.CGImage) { NSLog (@"*** error: image must be backed by a CGImage: %@", self); return nil; } if (maskImage && !maskImage.CGImage) { NSLog (@"*** error: maskImage must be backed by a CGImage: %@", maskImage); return nil; } CGRect imageRect = { CGPointZero, self.size }; UIImage *effectImage = self; BOOL hasBlur = blurRadius > __FLT_EPSILON__; BOOL hasSaturationChange = fabs(saturationDeltaFactor - 1.) > __FLT_EPSILON__; if (hasBlur || hasSaturationChange) { UIGraphicsBeginImageContextWithOptions(self.size, NO, [[UIScreen mainScreen] scale]); CGContextRef effectInContext = UIGraphicsGetCurrentContext(); CGContextScaleCTM(effectInContext, 1.0, -1.0); CGContextTranslateCTM(effectInContext, 0, -self.size.height); CGContextDrawImage(effectInContext, imageRect, self.CGImage); vImage_Buffer effectInBuffer; effectInBuffer.data = CGBitmapContextGetData(effectInContext); effectInBuffer.width = CGBitmapContextGetWidth(effectInContext); effectInBuffer.height = CGBitmapContextGetHeight(effectInContext); effectInBuffer.rowBytes = CGBitmapContextGetBytesPerRow(effectInContext); UIGraphicsBeginImageContextWithOptions(self.size, NO, [[UIScreen mainScreen] scale]); CGContextRef effectOutContext = UIGraphicsGetCurrentContext(); vImage_Buffer effectOutBuffer; effectOutBuffer.data = CGBitmapContextGetData(effectOutContext); effectOutBuffer.width = CGBitmapContextGetWidth(effectOutContext); effectOutBuffer.height = CGBitmapContextGetHeight(effectOutContext); effectOutBuffer.rowBytes = CGBitmapContextGetBytesPerRow(effectOutContext); if (hasBlur) { // A description of how to compute the box kernel width from the Gaussian // radius (aka standard deviation) appears in the SVG spec: // http://www.w3.org/TR/SVG/filters.html#feGaussianBlurElement // // For larger values of 's' (s >= 2.0), an approximation can be used: Three // successive box-blurs build a piece-wise quadratic convolution kernel, which // approximates the Gaussian kernel to within roughly 3%. // // let d = floor(s * 3*sqrt(2*pi)/4 + 0.5) // // ... if d is odd, use three box-blurs of size 'd', centered on the output pixel. // CGFloat inputRadius = blurRadius * [[UIScreen mainScreen] scale]; NSUInteger radius = floor(inputRadius * 3. * sqrt(2 * M_PI) / 4 + 0.5); if (radius % 2 != 1) { radius += 1; // force radius to be odd so that the three box-blur methodology works. } vImageBoxConvolve_ARGB8888(&effectInBuffer, &effectOutBuffer, NULL, 0, 0, radius, radius, 0, kvImageEdgeExtend); vImageBoxConvolve_ARGB8888(&effectOutBuffer, &effectInBuffer, NULL, 0, 0, radius, radius, 0, kvImageEdgeExtend); vImageBoxConvolve_ARGB8888(&effectInBuffer, &effectOutBuffer, NULL, 0, 0, radius, radius, 0, kvImageEdgeExtend); } BOOL effectImageBuffersAreSwapped = NO; if (hasSaturationChange) { CGFloat s = saturationDeltaFactor; CGFloat floatingPointSaturationMatrix[] = { 0.0722 + 0.9278 * s, 0.0722 - 0.0722 * s, 0.0722 - 0.0722 * s, 0, 0.7152 - 0.7152 * s, 0.7152 + 0.2848 * s, 0.7152 - 0.7152 * s, 0, 0.2126 - 0.2126 * s, 0.2126 - 0.2126 * s, 0.2126 + 0.7873 * s, 0, 0, 0, 0, 1, }; const int32_t divisor = 256; NSUInteger matrixSize = sizeof(floatingPointSaturationMatrix)/sizeof(floatingPointSaturationMatrix[0]); int16_t saturationMatrix[matrixSize]; for (NSUInteger i = 0; i < matrixSize; ++i) { saturationMatrix[i] = (int16_t)roundf(floatingPointSaturationMatrix[i] * divisor); } if (hasBlur) { vImageMatrixMultiply_ARGB8888(&effectOutBuffer, &effectInBuffer, saturationMatrix, divisor, NULL, NULL, kvImageNoFlags); effectImageBuffersAreSwapped = YES; } else { vImageMatrixMultiply_ARGB8888(&effectInBuffer, &effectOutBuffer, saturationMatrix, divisor, NULL, NULL, kvImageNoFlags); } } if (!effectImageBuffersAreSwapped) effectImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); if (effectImageBuffersAreSwapped) effectImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } // Set up output context. UIGraphicsBeginImageContextWithOptions(self.size, NO, [[UIScreen mainScreen] scale]); CGContextRef outputContext = UIGraphicsGetCurrentContext(); CGContextScaleCTM(outputContext, 1.0, -1.0); CGContextTranslateCTM(outputContext, 0, -self.size.height); // Draw base image. CGContextDrawImage(outputContext, imageRect, self.CGImage); // Draw effect image. if (hasBlur) { CGContextSaveGState(outputContext); if (maskImage) { CGContextClipToMask(outputContext, imageRect, maskImage.CGImage); } CGContextDrawImage(outputContext, imageRect, effectImage.CGImage); CGContextRestoreGState(outputContext); } // Add in color tint. if (tintColor) { CGContextSaveGState(outputContext); CGContextSetFillColorWithColor(outputContext, tintColor.CGColor); CGContextFillRect(outputContext, imageRect); CGContextRestoreGState(outputContext); } // Output image is ready. UIImage *outputImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return outputImage; } - (UIImage*) blurredSnapshot{ UIColor *tintColor = [UIColor colorWithWhite:0.8 alpha:0.7]; // UIColor *tintColor = [UIColor colorWithRed:255.0/255.0 green:255.0/255.0 blue:255.0/255.0 alpha:0.5]; UIImage *image = [self applyBlurWithRadius:5 tintColor:tintColor saturationDeltaFactor:1.8 maskImage:nil]; return image; } @end // // BlurView.h // // Created by Ankit Thakur on 07/03/14. // #import <UIKit/UIKit.h> typedef NS_ENUM(NSUInteger, BlurViewType) { BlurSubView, BlurPopView }; typedef NS_ENUM(NSUInteger, BlurViewColorType) { BlurWhiteView, BlurBlackView }; @interface BlurView : UIView - (void) blurBackgroundWithScreenshotView:(UIView*)screenshotView withType:(BlurViewType)type withColor:(BlurViewColorType)colorType withPoint:(CGPoint)point; @end // // BlurView.m // // Created by Ankit Thakur on 07/03/14. // #import "BlurView.h" #import "UIImage+Blur.h" @interface BlurView (){ } @end @implementation BlurView - (id)initWithCoder:(NSCoder *)aDecoder { self = [super initWithCoder:aDecoder]; if (self) { // Initialization code } return self; } - (void) blurBackgroundWithScreenshotView:(UIView*)screenshotView withType:(BlurViewType)type withColor:(BlurViewColorType)colorType withPoint:(CGPoint)point{ NSLog(@"%ld",(long)screenshotView.tag); if ([self viewWithTag:111]) { [[self viewWithTag:111] removeFromSuperview]; } @autoreleasepool { UIGraphicsBeginImageContext(screenshotView.frame.size); if([self respondsToSelector:@selector(drawViewHierarchyInRect:afterScreenUpdates:)]){ [screenshotView drawViewHierarchyInRect:self.frame afterScreenUpdates:NO]; } else{ [screenshotView.layer renderInContext:UIGraphicsGetCurrentContext()]; } UIGraphicsEndImageContext(); CGPoint origin = self.frame.origin; switch (type) { case BlurSubView: origin.x = - origin.x; origin.y = -origin.y; break; case BlurPopView: origin.x = -point.x; origin.y = -point.y; break; default: break; } UIImage *blurImage = nil; UIGraphicsBeginImageContext(self.bounds.size); CGContextTranslateCTM(UIGraphicsGetCurrentContext(), origin.x, origin.y); [screenshotView.layer renderInContext:UIGraphicsGetCurrentContext()]; blurImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); NSData *imageData = UIImageJPEGRepresentation(blurImage, 1.0); blurImage = [UIImage imageWithData:imageData]; switch (colorType) { case BlurWhiteView: blurImage = [blurImage blurredWhiteSnapshot]; break; case BlurBlackView: blurImage = [blurImage blurredBlackSnapshot]; break; default: break; } UIImageView *imageView = [[UIImageView alloc] initWithFrame:self.bounds]; imageView.tag = 111; imageView.image = blurImage; [self addSubview:imageView]; [self sendSubviewToBack:imageView]; blurImage = nil; } } @end
最简单的方法和干净的方法是只是拖动它或你的UIView 。 你需要在视觉效果视图中设置AutoLayout Constrain。
选中的是视觉效果视图