Android 9 Development Cookbook - Third Edition

Setting up the camera preview

Here's a rundown on how the code sets up the preview:

1. First, we set up the TextureView.SurfaceTextureListener with the setSurfaceTextureListener() method in onCreate()
2. When we get the onSurfaceTextureAvailable() callback, we open the camera
3. We pass our CameraDevice.StateCallback class to the openCamera() method, which eventually calls the onOpened() callback
4. onOpened() gets the surface for the preview by calling getSurfaceTexture() and passes it to the CameraDevice by calling createCaptureSession()
5. Finally, when CameraCaptureSession.StateCallback onConfigured() is called, we start the preview with the setRepeatingRequest() method