本篇介绍

回顾下Camera1，使用起来需要开发关注很多细节，Camera2可以帮助开发自动处理很多细节，可是使用上就特别复杂，Android就提供了Camerax，既简单又好用，本篇介绍下使用方法。

使用步骤

1. 申请权限

 <uses-permission android:name="android.permission.CAMERA" />

动态申请:

 private void requestPermission() {
        if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) {
            return;
        }
        ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA}, CAMERA_REQUEST_CODE);
    }

1. 打开Camera:

mCameraProviderFuture = ProcessCameraProvider.getInstance(this);
        mCameraProviderFuture.addListener(new Runnable() {
            @Override
            public void run() {
                try {
                    ProcessCameraProvider cameraProvider = mCameraProviderFuture.get();

                    Preview preview = new Preview.Builder().build();
                    ImageAnalysis imageAnalysis =
                            new ImageAnalysis.Builder().setTargetResolution(new Size(1280, 720)).build();
                    CameraSelector cameraSelector = CameraSelector.Builder.fromSelector(CameraSelector.DEFAULT_FRONT_CAMERA).build();

                    cameraProvider.unbind();
                    cameraProvider.bindToLifecycle(MainActivity.this, cameraSelector, imageAnalysis, preview);
                    preview.setSurfaceProvider(mPreview.getSurfaceProvider());

                } catch (ExecutionException e) {
                    e.printStackTrace();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }, ContextCompat.getMainExecutor(this));

这就是打开Camera，并且将采集数据渲染出来的全部代码了，很简单。

1. 关闭Camera:

   try {
            mCameraProviderFuture.get().shutdown();
        } catch (ExecutionException e) {
            e.printStackTrace();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }