如何在访问相机时检查图像为零并在相机上按取消

Posted 2023-05-07

【中文标题】如何在访问相机时检查图像为零并在相机上按取消

【英文标题】：How to to check image nil when access to camera and press cancel on camera

【发布时间】：2019-07-05 02:28:34

【问题描述】：

访问相机时如何检查图像为零并在相机上按取消

我接受了测试 第一步

按下拍照按钮 访问摄像头
按取消我在输出面板上得到值 检查图像拍照 ==> 可选(UIImagePickerController: 0x107879a00) 在项目上按保存按钮照片 我的价值为零 致命错误：在展开可选值时意外发现 nil 2019-07-05 08:52:24.667938+0700 MyProject[2307:786209] 致命错误：在展开可选值时意外发现 nil

我接受了测试 第二步

拍照

2.按相机上的使用照片 在相机上拍照使用照片

检查图像拍照 ==> 可选（UIImagePickerController: 0x10286ca00）

我想检查相机上的案例取消并返回按项目上的保存按钮

如何解决……这种情况 下面是我的代码

拍照

 @IBAction func takePhotoReturnOfSealButton(_ sender: UIButton) 
        imagePickerStoreListReturnSealLock = UIImagePickerController()
        imagePickerStoreListReturnSealLock.delegate = self
        imagePickerStoreListReturnSealLock.sourceType = .camera
        present(imagePickerStoreListReturnSealLock,animated: true, completion: nil)
        print("Check image take photo ==> \(String(describing: imagePickerStoreListReturnSealLock))")
    //takePhotoReturnOfSealButton

保存照片

@IBAction func saveImageToDevice(_ sender: UIButton) 
        //Save photo to device not success have nil value
        if(imagePickerStoreListReturnSealLock == nil)
            showAlert(title: "No Have Photo", message: "Please take photo")
            print("Check image cannot save ==> \(String(describing: imagePickerStoreListReturnSealLock))")
        else
//          Save photo to device success
            UIImageWriteToSavedPhotosAlbum(showImageTakePhotoReturnOfSeal.image!, self, #selector(image(_:didFinishSavingWithError:contextInfo:)), nil)
            print("Check image Save to device ==> \(String(describing: showImageTakePhotoReturnOfSeal))")
        
    //saveImageToDevice

【参考方案1】：

每当您取消图像选择器时，都会调用一个委托方法 -

func imagePickerControllerDidCancel(_ picker: UIImagePickerController) 
    //Perform your action when cancel has been pressed

这个方法在图像被拾取时被调用 -

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) 
   if picker == imagePicker 
        //Save your image
        imagePicker.dismiss(animated: true, completion: nil)
   

记得在上面定义这个 -

var imagePicker = UIImagePickerController()

在 viewDidLoad 中

imagePicker.delegate = self

【参考方案2】：

当您点击取消图像选择器时，将调用以下委托方法：

public func imagePickerControllerDidCancel(_ picker: UIImagePickerController) 
        picker.dismiss(animated: true, completion: nil)
    

当你选择一张图片时，会调用下面的委托方法：

    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) 
            let image : UIImage = info[UIImagePickerController.InfoKey.originalImage] as! UIImage
            picker.dismiss(animated: true, completion: nil)
            UIImageWriteToSavedPhotosAlbum(image!, nil, nil, nil)//to save image in saved photo album
        

希望对你有帮助