ProcessCameraProvider

bindToLifecycle

public Camera bindToLifecycle (LifecycleOwner lifecycleOwner, 
                CameraSelector cameraSelector, 
                UseCase... useCases)

Binds the collection of UseCase to a LifecycleOwner.

The state of the lifecycle will determine when the cameras are open, started, stopped and closed. When started, the use cases receive camera data.

Binding to a lifecycleOwner in state currently in Lifecycle.State.STARTED or greater will also initialize and start data capture. If the camera was already running this may cause a new initialization to occur temporarily stopping data from the camera before restarting it.

Multiple use cases can be bound via adding them all to a single bindToLifecycle call, or by using multiple bindToLifecycle calls. Using a single call that includes all the use cases helps to set up a camera session correctly for all uses cases, such as by allowing determination of resolutions depending on all the use cases bound being bound. If the use cases are bound separately, it will find the supported resolution with the priority depending on the binding sequence. If the use cases are bound with a single call, it will find the supported resolution with the priority in sequence of ImageCapture, Preview and then ImageAnalysis. The resolutions that can be supported depends on the camera device hardware level that there are some default guaranteed resolutions listed in CameraDevice.createCaptureSession(List, android.hardware.camera2.CameraCaptureSession.StateCallback, Handler).

Currently up to 3 use cases may be bound to a Lifecycle at any time. Exceeding capability of target camera device will throw an IllegalArgumentException.

A UseCase should only be bound to a single lifecycle and camera selector a time. Attempting to bind a use case to a lifecycle when it is already bound to another lifecycle is an error, and the use case binding will not change. Attempting to bind the same use case to multiple camera selectors is also an error and will not change the binding.

If different use cases are bound to different camera selectors that resolve to distinct cameras, but the same lifecycle, only one of the cameras will operate at a time. The non-operating camera will not become active until it is the only camera with use cases bound.

The Camera returned is determined by the given camera selector, plus other internal requirements, possibly from use case configurations. The camera returned from bindToLifecycle may differ from the camera determined solely by a camera selector. If the camera selector can't resolve a camera under the requirements, an IllegalArgumentException will be thrown.

Only UseCase bound to latest active Lifecycle can keep alive. UseCase bound to other Lifecycle will be stopped.

getInstance

public static ListenableFuture<ProcessCameraProvider> getInstance (Context context)

Retrieves the ProcessCameraProvider associated with the current process.

The instance returned here can be used to bind use cases to any LifecycleOwner with bindToLifecycle(LifecycleOwner, CameraSelector, UseCase).

The instance's configuration may be customized by subclassing the application's Application class and implementing CameraXConfig.Provider. For example, the following will initialize this process camera provider with a Camera2 implementation from androidx.camera.camera2, and with a custom executor.

 public class MyApplication extends Application implements CameraXConfig.Provider {
     @Override
     public CameraXConfig getCameraXConfig() {
         return CameraXConfig.Builder.fromConfig(Camera2Config.defaultConfig())
                    .setCameraExecutor(myExecutor)
                    .build();
     }

     . . .
 }
 

hasCamera

public boolean hasCamera (CameraSelector cameraSelector)

isBound

public boolean isBound (UseCase useCase)

unbind

public void unbind (UseCase... useCases)

unbindAll

public void unbindAll ()