SurfaceView如何重新创建，如果已经被破坏
我通过SurfaceView创建了一个相机，但是当我按回家并返回到活动。 SurfaceView没有显示任何东西。 它没有调用surfaceCreated(SurfaceHolder holder)
当我回到活动。 我该怎么办？
这里是我的代码写的kotlin类`MyCameraView：SurfaceView，SurfaceHolder.Callback，Camera.PreviewCallback，Camera.FaceDetectionListener {
private lateinit var mCamera : Camera var sizes : List<Camera.Size>? = null constructor( ctx : Context, attrs : AttributeSet?) : super(ctx,attrs){ holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); holder.addCallback(this) } constructor(ctx : Context):this(ctx,null){ } override fun surfaceChanged(p0: SurfaceHolder?, format: Int, width: Int, height: Int) { Log.e("MyCameraView","CHANGE ") val sizes = mCamera.parameters.supportedPreviewSizes val size = getOptimalSzie(sizes) val supportWith = size.height val supportHeight : Int = size.width val radio : Float = width.toFloat()/supportWith setMeasuredDimension(width,(supportHeight*radio).toInt()) layout(0, (-(supportHeight*radio)/5).toInt(),width, ((supportHeight*radio).toInt()-(supportHeight*radio)/5).toInt()) } override fun surfaceDestroyed(p0: SurfaceHolder?) { Log.e("MyCameraView","DESTORY") holder.removeCallback(this) mCamera.setPreviewCallback(null) mCamera.stopFaceDetection() mCamera.stopPreview() mCamera.lock() mCamera.release() } override fun surfaceCreated(p0: SurfaceHolder?) { Log.e("MyCameraView","OPEN") mCamera = Camera.open(Camera.CameraInfo.CAMERA_FACING_FRONT) mCamera.setDisplayOrientation(90) mCamera.setPreviewCallback(this) mCamera.setPreviewDisplay(holder) mCamera.setFaceDetectionListener(this) mCamera.startPreview(); mCamera.startFaceDetection() } private fun getOptimalSzie(sizes: List<Camera.Size>): Camera.Size { var pos = 0 var ratio = 0 var viewRatio = height/width sizes.forEachIndexed { index, size -> val curRatio = size.width/size.height if(ratio == 0 ) ratio = curRatio else if( (viewRatio - curRatio) < (viewRatio - ratio) ){ ratio = curRatio pos = index } } return sizes[pos] } override fun onPreviewFrame(data: ByteArray?, camera: Camera) { if(allowTake) { val parameters = camera.getParameters() val width = parameters.previewSize.width val height = parameters.previewSize.height val yuv = YuvImage(data, parameters.previewFormat, width, height, null) val out = ByteArrayOutputStream() yuv.compressToJpeg(Rect(0, 0, width, height), 50, out) val bytes = out.toByteArray() val b = BitmapFactory.decodeByteArray(bytes, 0, bytes.size) detected?.invoke(bytes) allowTake = false hasTake = true } } var hasTake = false private var allowTake = false override fun onFaceDetection(faces: Array<out Camera.Face>?, camera: Camera?) { if(!hasTake) { allowTake = true } } private var detected: ((bitmap : ByteArray) -> Unit)? = null fun onFaceDetected(detected : ( bitmap : ByteArray )->Unit){ this.detected = detected } }
我解决了！ 我改变使用TextureView。 它有四个回调方法。 这是其中之一
onSurfaceTextureAvailable(surface: SurfaceTexture?, width: Int, height: Int)
它被称为，而我回到了活动！ 所以我可以打开相机，当我回来了