ios - AVCapturePhotoCaptureDelegate 方法不是每次都被调用

Question

我正在构建一个自定义相机，并且得到了古怪的结果。当我 try catch 图像时，有时 没有收到预期的委托(delegate)回调。例如，这是我的委托(delegate)方法:

func photoOutput(_ output: AVCapturePhotoOutput, willBeginCaptureFor resolvedSettings: AVCaptureResolvedPhotoSettings) {
    print("will begin")
}

func photoOutput(_ output: AVCapturePhotoOutput, willCapturePhotoFor resolvedSettings: AVCaptureResolvedPhotoSettings) {
    print("will capture")
}

func photoOutput(_ output: AVCapturePhotoOutput, didCapturePhotoFor resolvedSettings: AVCaptureResolvedPhotoSettings) {
    print("did capture")
}

func photoOutput(_ output: AVCapturePhotoOutput, didFinishCaptureFor resolvedSettings: AVCaptureResolvedPhotoSettings, error: Error?) {
    print("finished capture")
}

func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {
    print("finish process")
}

我有一个触发以下方法的按钮:

func capture() {
    print("capture called")
    let settings = AVCapturePhotoSettings()
    captureOutput.capturePhoto(with: settings, delegate: self)
}

每次调用此方法时，我都希望在控制台中输出以下内容:

capture called

will begin
will capture
did capture
finish process
finished capture
image set

但是，我似乎只有 50/50 的机会得到以下输出:

capture called
did capture

这是怎么回事？

Answer 1

我遇到了同样的问题。我无法深入了解它，但我可以通过将输出从 AVCapturePhotoOutput 切换到 AVCaptureVideoDataOutput 来绕过它。我发现这篇文章真的很有帮助:https://medium.com/@barbulescualex/making-a-custom-camera-in-ios-ea44e3087563