App設計時往往會用到一些模糊效果或者毛玻璃效果,iOS目前已提供一些模糊API可以讓我們方便是使用。
話說蘋果在iOS7.0之后,很多系統界面都使用了毛玻璃效果,增加了界面的美觀性,比如下圖的通知中心界面;
但是其iOS7.0的SDK并沒有提供給開發者實現毛玻璃效果的API,所以很多人都是通過一些別人封裝的框架來實現,后面我也會講到一個;
其實在iOS7.0(包括)之前還是有系統的類可以實現毛玻璃效果的, 就是 UIToolbar這個類,并且使用相當簡單,幾行代碼就可以搞定.
下面是代碼實現:
創建一個UIToolbar實例,設置它的frame或者也可以通過添加約束
然后UIToolbar有一個屬性:barStyle,設置對應的枚舉值來呈現毛玻璃的樣式,最后再添加到需要進行毛玻璃效果的view上即可.
/*毛玻璃的樣式(枚舉)UIBarStyleDefault = ,UIBarStyleBlack = ,UIBarStyleBlackOpaque = , // Deprecated. Use UIBarStyleBlackUIBarStyleBlackTranslucent = , // Deprecated. Use UIBarStyleBlack and set the translucent property to YES*/UIImageView *bgImgView = [[UIImageView alloc] initWithFrame:self.view.bounds];bgImgView.image = [UIImage imageNamed:@"huoying.jpg"];[self.view addSubview:bgImgView];UIToolbar *toolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(, , bgImgView.frame.size.width*., bgImgView.frame.size.height)];toolbar.barStyle = UIBarStyleBlackTranslucent;[bgImgView addSubview:toolbar];
效果圖:
我們再來看看視圖結構:
通過視圖結構可以看到UIToolbar包含了三個子視圖
一個背景圖片和1個背景view,還有1個背景特效view,正是這幾個視圖結合在一起實現了毛玻璃的效果
在iOS8.0之后,蘋果新增了一個類UIVisualEffectView,通過這個類來實現毛玻璃效果與上面的UIToolbar一樣,而且效率也非常之高,使用也是非常簡單,幾行代碼搞定. UIVisualEffectView是一個抽象類,不能直接使用,需通過它下面的三個子類來實現(UIBlurEffect, UIVisualEffevt, UIVisualEffectView);
子類UIBlurEffect只有一個類方法,用來快速創建一個毛玻璃效果,參數是一個枚舉,用來設置毛玻璃的樣式,而UIVisualEffectView則多了兩個屬性和兩個構造方法,用來快速將創建的毛玻璃添加到這個UIVisualEffectView上.
特別注意: 這個類是iOS8.0之后才適用, 所以如果項目要兼容iOS7.0的話, 還是要考慮其它的兩種方法了.
下面來看看實現代碼:
同樣是先快速的實例化UIBlurEffect并設置毛玻璃的樣式,然后再通過UIVisualEffectView的構造方法將UIBlurEffect的實例添加上去最后設置frame或者是通過添加約束, 將effectView添加到要實現了毛玻璃的效果的view控件上,效果圖和上面的一樣.
UIImageView *bgImgView = [[UIImageView alloc] initWithFrame:self.view.bounds];bgImgView.image = [UIImage imageNamed:@"huoying.jpg"];bgImgView.contentMode = UIViewContentModeScaleAspectFill;//[bgImgView setImageToBlur: [UIImage imageNamed:@"huoying.jpg"] blurRadius: completionBlock:nil];bgImgView.userInteractionEnabled = YES;[self.view addSubview:bgImgView];/*毛玻璃的樣式(枚舉)UIBlurEffectStyleExtraLight,UIBlurEffectStyleLight,UIBlurEffectStyleDark*/UIBlurEffect *effect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleDark];UIVisualEffectView *effectView = [[UIVisualEffectView alloc] initWithEffect:effect];effectView.frame = CGRectMake(, , bgImgView.frame.size.width*., bgImgView.frame.size.height);[bgImgView addSubview:effectView];
但是我們來看看視圖結構,大家會發現和Toolbar不一樣哦!
其實是因為UIVisualEffectView這個類,構造方法幫我們創建了一個view,而這個view我們給它做了毛玻璃處理,再將其覆蓋到了背景圖之上
嗯! 最后再來給大家介紹一個國外大神封裝的UIImageView的分類,里面不管是怎么實現的,反正使用非常簡單,只要一句代碼就搞定.
下面先看代碼:
UIImageView *bgImgView = [[UIImageView alloc] initWithFrame:self.view.bounds];//bgImgView.image = [UIImage imageNamed:@"huoying.jpg"];bgImgView.contentMode = UIViewContentModeScaleAspectFill;// 對背景圖片進行毛玻璃效果處理 參數blurRadius默認是,可指定,最后一個參數block回調可以為nil[bgImgView setImageToBlur: [UIImage imageNamed:@"huoying.jpg"] blurRadius: completionBlock:nil];bgImgView.userInteractionEnabled = YES;[self.view addSubview:bgImgView];
效果圖:
再來看看添加毛玻璃效果后的視圖結構:
哈哈哈, 大家應該看懂了, 這是直接對背景圖片進行了高斯模糊處理了,其它就不解釋了.
好啦, 反正iOS中要進行毛玻璃效果處理就這幾種方式,看大家的需求,喜歡用哪種就用哪種吧.
上面的demo,包括大神封裝的分類,如果需要詳細的源代碼的話,可以到我的gitHub上Clone啦!有問題歡迎留言一起探討學習.
下面給大家介紹圖片模糊效果的三種方法
第一種使用Core Image進行模糊
- (UIImage *)blurryImage:(UIImage *)image withBlurLevel:(CGFloat)blur { CIImage *inputImage = [CIImage imageWithCGImage:image.CGImage]; CIFilter *filter = [CIFilter filterWithName:@"CIGaussianBlur" keysAndValues:kCIInputImageKey, inputImage, @"inputRadius", @(blur), ]; CIImage *outputImage = filter.outputImage; CGImageRef outImage = [self.context createCGImage:outputImage fromRect:[outputImage extent]]; return [UIImage imageWithCGImage:outImage]; }第二種使用vImage API進行模糊
- (UIImage *)blurryImage:(UIImage *)image withBlurLevel:(CGFloat)blur { if (blur < 0.f || blur > 1.f) { blur = 0.5f; } int boxSize = (int)(blur * 100); boxSize = boxSize - (boxSize % 2) + 1; CGImageRef img = image.CGImage; vImage_Buffer inBuffer, outBuffer; vImage_Error error; void *pixelBuffer; CGDataProviderRef inProvider = CGImageGetDataProvider(img); CFDataRef inBitmapData = http://www.open-open.com/code/view/CGDataProviderCopyData(inProvider); inBuffer.width = CGImageGetWidth(img); inBuffer.height = CGImageGetHeight(img); inBuffer.rowBytes = CGImageGetBytesPerRow(img); inBuffer.data = (void*)CFDataGetBytePtr(inBitmapData); pixelBuffer = malloc(CGImageGetBytesPerRow(img) * CGImageGetHeight(img)); if(pixelBuffer == NULL) NSLog(@"No pixelbuffer"); outBuffer.data = pixelBuffer; outBuffer.width = CGImageGetWidth(img); outBuffer.height = CGImageGetHeight(img); outBuffer.rowBytes = CGImageGetBytesPerRow(img); error = vImageBoxConvolve_ARGB8888(&inBuffer, &outBuffer, NULL, 0, 0, boxSize, boxSize, NULL, kvImageEdgeExtend); if (error) { NSLog(@"error from convolution %ld", error); } CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef ctx = CGBitmapContextCreate( outBuffer.data, outBuffer.width, outBuffer.height, 8, outBuffer.rowBytes, colorSpace, kCGImageAlphaNoneSkipLast); CGImageRef imageRef = CGBitmapContextCreateImage (ctx); UIImage *returnImage = [UIImage imageWithCGImage:imageRef]; //clean up CGContextRelease(ctx); CGColorSpaceRelease(colorSpace); free(pixelBuffer); CFRelease(inBitmapData); CGColorSpaceRelease(colorSpace); CGImageRelease(imageRef); return returnImage; } 第三種方法是網上找到的(毛玻璃效果)
// 內部方法,核心代碼,封裝了毛玻璃效果 參數:半徑,顏色,色彩飽和度- (UIImage *)imageBluredWithRadius:(CGFloat)blurRadius tintColor:(UIColor *)tintColor saturationDeltaFactor:(CGFloat)saturationDeltaFactor maskImage:(UIImage *)maskImage { 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 = http://www.open-open.com/code/view/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) { 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, (short)radius, (short)radius, 0, kvImageEdgeExtend); vImageBoxConvolve_ARGB8888(&effectOutBuffer, &effectInBuffer, NULL, 0, 0, (short)radius, (short)radius, 0, kvImageEdgeExtend); vImageBoxConvolve_ARGB8888(&effectInBuffer, &effectOutBuffer, NULL, 0, 0, (short)radius, (short)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(); } // 開啟上下文 用于輸出圖像 UIGraphicsBeginImageContextWithOptions(self.size, NO, [[UIScreen mainScreen] scale]); CGContextRef outputContext = UIGraphicsGetCurrentContext(); CGContextScaleCTM(outputContext, 1.0, -1.0); CGContextTranslateCTM(outputContext, 0, -self.size.height); // 開始畫底圖 CGContextDrawImage(outputContext, imageRect, self.CGImage); // 開始畫模糊效果 if (hasBlur){ CGContextSaveGState(outputContext); if (maskImage) { CGContextClipToMask(outputContext, imageRect, maskImage.CGImage); } CGContextDrawImage(outputContext, imageRect, effectImage.CGImage); CGContextRestoreGState(outputContext); } // 添加顏色渲染 if (tintColor){ CGContextSaveGState(outputContext); CGContextSetFillColorWithColor(outputContext, tintColor.CGColor); CGContextFillRect(outputContext, imageRect); CGContextRestoreGState(outputContext); } // 輸出成品,并關閉上下文 UIImage *outputImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return outputImage;}新聞熱點
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