我正在使用a UITableviewcontroller,我希望页脚视图始终位于屏幕的底部.然而,y所述的位置页脚视图正在改变,因为每height的tableviewcell.我怎么能一直坚持到屏幕的底部?
我想NavigationBar只透明一个ViewController.但是,在更改NavigationBar单个内容后ViewController,整个navigationController变为透明,并在几秒钟后崩溃.这是我的代码块:
override func viewWillAppear(animated: Bool) {
self.navigationController!.navigationBar.setBackgroundImage(UIImage(), forBarMetrics: UIBarMetrics.Default)
self.navigationController?.navigationBar.shadowImage = UIImage()
self.navigationController?.navigationBar.translucent = true
self.navigationController!.view.backgroundColor = UIColor.clearColor()
}
override func viewDidDisappear(animated: Bool) {
self.navigationController!.navigationBar.setBackgroundImage(nil, forBarMetrics: UIBarMetrics.Default)
self.navigationController?.navigationBar.shadowImage = nil
self.navigationController?.navigationBar.translucent = true
}
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它崩溃了
self.navigationController!.navigationBar.setBackgroundImage(nil, forBarMetrics: UIBarMetrics.Default)
Run Code Online (Sandbox Code Playgroud) 一个实现了MVC模式的简单项目.到目前为止,我简要了解它是如何形成的,但我希望看到实际的实现.
因此SDWebImage 下载图像并存储到缓存中以获取密钥,这正是我想要在我的应用程序中执行的操作。我想将图像存储在密钥中并稍后获取图像。这是我的代码块:
SDWebImageManager.shared().imageDownloader?.downloadImage(with: URL.init(string: url), options: SDWebImageDownloaderOptions.highPriority, progress: { (receivedSize:Int,expectedSize:Int,url : URL?) in
print("progressing here in this block ")
}, completed: ({(image : UIImage, data : Data,error : Error, finished : Bool) in
print("reached in the completion block ")
if finished {
SDImageCache.shared().store(image, forKey: "d", toDisk: true, completion: nil)
} else {
print(error.localizedDescription)
showAlert(viewController: self, title: "", message: error.localizedDescription)
}
} as? SDWebImageDownloaderCompletedBlock))
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然而,完成块永远不会被调用。
我CGPoint在我的类中设置了一个常量UIViewController:
let point = gesture.location(in: gesture.view)
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这一点常数是CGPoint,但我需要它Int.有没有办法转换CGPoint成Int?