【发布时间】：2018-01-01 12:22:52
【问题描述】：
为什么我在运行程序时看不到我的按钮，但在 Xcode 8 中我可以看到它。它在视图上方，看起来就像您在 snapchat 中按下以拍照的按钮。
我是 Xcode 的新手，所以如果我需要了解有关 Xcode 或故事板的任何信息，可以帮助我解决这些问题，请告诉我。
视图代码：
import UIKit
import AVFoundation
import QuartzCore
class View1: UIViewController , AVCaptureVideoDataOutputSampleBufferDelegate{
let captureSession = AVCaptureSession()
var previewLayer: CALayer!
var captureDevice: AVCaptureDevice!
@IBOutlet weak var cameraView: UIView!
override func viewDidLoad() {
super.viewDidLoad()
}
/*
This is a function to prepair the camera
and check that there is a camera.
If there isn't a camera on the device
then get you will get a error.
*/
func prepareCamera()
{
captureSession.sessionPreset = AVCaptureSessionPreset1920x1080
if let availableDevices = AVCaptureDeviceDiscoverySession(deviceTypes: [.builtInWideAngleCamera],
mediaType: AVMediaTypeVideo,
position: .back).devices
{
captureDevice = availableDevices.first
beginSession()
}
}
func beginSession()
{
do
{
let captureDeviceInput = try AVCaptureDeviceInput(device: captureDevice)
captureSession.addInput(captureDeviceInput)
}
catch
{
print(error.localizedDescription)
/*
Figure out what to do here
*/
}
if let previewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
{
self.previewLayer = previewLayer
self.view.layer.addSublayer(
self.previewLayer)
self.previewLayer.frame = self.view.layer.frame
self.previewLayer.frame.size = self.view.layer.frame.size
captureSession.startRunning()
let dataOutput = AVCaptureVideoDataOutput()
dataOutput.videoSettings = [(kCVPixelBufferPixelFormatTypeKey as NSString
): NSNumber(value: kCVPixelFormatType_32BGRA)]
dataOutput.alwaysDiscardsLateVideoFrames = true
if captureSession.canAddOutput(dataOutput)
{
captureSession.addOutput(dataOutput)
}
captureSession.commitConfiguration()
let queue = DispatchQueue(label: "com.PhotoAllergy.captureQueue")
dataOutput.setSampleBufferDelegate(self, queue: queue)
}
}
//func captureOutput(_ captureOutput: AVCaptureOutput!, didDrop sampleBuffer: CMSampleBuffer!, from connection: AVCaptureConnection!) {
//yeeye
//}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
prepareCamera()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
【问题讨论】：
-
请附上您的视图控制器在 Storyboard 中的样子以及运行代码时的样子。如果您从代码中添加任何 UI 元素，请在您的问题中包含代码。你在使用自动布局吗？
-
您是否在按钮视图中添加了足够的约束？
-
添加一些截图！
-
@sabarivasagan 我不能因为我需要声誉:(
-
可能是您正在添加，但它不在视野范围内并且不可见。为您的按钮添加约束并查看包含它。
标签： ios iphone autolayout storyboard