在新iOS的音乐应用程序中,我们可以看到一个模糊的视图后面有一个专辑封面。
这样的事情是如何完成的呢?我看了文件,但什么都没发现。
在新iOS的音乐应用程序中,我们可以看到一个模糊的视图后面有一个专辑封面。
这样的事情是如何完成的呢?我看了文件,但什么都没发现。
当前回答
这是乔伊回答的重要补充
这适用于你想用UINavigationController呈现一个模糊背景的UIViewController的情况。
// suppose you've done blur effect with your presented view controller
UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController];
// this is very important, if you don't do this, the blur effect will darken after view did appeared
// the reason is that you actually present navigation controller, not presented controller
// please note it's "OverFullScreen", not "OverCurrentContext"
nav.modalPresentationStyle = UIModalPresentationOverFullScreen;
UIViewController *presentedViewController = [[UIViewController alloc] init];
// the presented view controller's modalPresentationStyle is "OverCurrentContext"
presentedViewController.modalPresentationStyle = UIModalPresentationOverCurrentContext;
[presentingViewController presentViewController:nav animated:YES completion:nil];
享受吧!
其他回答
func blurBackgroundUsingImage(image: UIImage)
{
var frame = CGRectMake(0, 0, self.view.frame.width, self.view.frame.height)
var imageView = UIImageView(frame: frame)
imageView.image = image
imageView.contentMode = .ScaleAspectFill
var blurEffect = UIBlurEffect(style: .Light)
var blurEffectView = UIVisualEffectView(effect: blurEffect)
blurEffectView.frame = frame
var transparentWhiteView = UIView(frame: frame)
transparentWhiteView.backgroundColor = UIColor(white: 1.0, alpha: 0.30)
var viewsArray = [imageView, blurEffectView, transparentWhiteView]
for index in 0..<viewsArray.count {
if let oldView = self.view.viewWithTag(index + 1) {
var oldView = self.view.viewWithTag(index + 1)
// Must explicitly unwrap oldView to access its removeFromSuperview() method as of Xcode 6 Beta 5
oldView!.removeFromSuperview()
}
var viewToInsert = viewsArray[index]
self.view.insertSubview(viewToInsert, atIndex: index + 1)
viewToInsert.tag = index + 1
}
}
苹果为UIImage类提供了一个名为UIImage+ImageEffects.h的扩展。在这个类中,您可以使用所需的方法来模糊视图
简单的答案是添加一个子视图并改变它的alpha。
UIView *mainView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 200, 200)];
UIView *subView = [[UIView alloc] initWithFrame:popupView.frame];
UIColor * backImgColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"blue_Img.png"]];
subView.backgroundColor = backImgColor;
subView.alpha = 0.5;
[mainView addSubview:subView];
下面是Swift中使用CIGaussianBlur的快速实现:
func blur(image image: UIImage) -> UIImage {
let radius: CGFloat = 20;
let context = CIContext(options: nil);
let inputImage = CIImage(CGImage: image.CGImage!);
let filter = CIFilter(name: "CIGaussianBlur");
filter?.setValue(inputImage, forKey: kCIInputImageKey);
filter?.setValue("\(radius)", forKey:kCIInputRadiusKey);
let result = filter?.valueForKey(kCIOutputImageKey) as! CIImage;
let rect = CGRectMake(radius * 2, radius * 2, image.size.width - radius * 4, image.size.height - radius * 4)
let cgImage = context.createCGImage(result, fromRect: rect);
let returnImage = UIImage(CGImage: cgImage);
return returnImage;
}
在Xcode中你可以很容易地做到。遵循xcode中的步骤。在你的uiview或imageview上拖动视觉效果视图。
快乐编码:)