1.ISurfaceHolder.AddCallback(this):这里回调函数添加的内容是当前的Activity，当前Activity需实现ISurfaceHolderCallback接口，并实现接口方法
public void SurfaceChanged(ISurfaceHolder holder, Android.Graphics.Format format, int width, int height) { //throw new NotImplementedException(); } public void SurfaceCreated(ISurfaceHolder holder) { //throw new NotImplementedException(); this.InintCamera(); } public void SurfaceDestroyed(ISurfaceHolder holder) { //throw new NotImplementedException(); if (this.camera != null) { if (this.isPreview) { this.camera.StopPreview(); this.camera.Release(); this.camera = null; } } }2.Camera.Open(); 报错：java.lang.RuntimeException: Fail to connect to camera service
解决：未赋Camera权限：android.permission.CAMERA
