StateCallback

ERROR_CAMERA_DEVICE

static val ERROR_CAMERA_DEVICE: Int

An error code that can be reported by onError indicating that the camera device has encountered a fatal error.

The camera device needs to be re-opened to be used again.

Value: 4

ERROR_CAMERA_DISABLED

static val ERROR_CAMERA_DISABLED: Int

An error code that can be reported by onError indicating that the camera device could not be opened due to a device policy.

Value: 3

ERROR_CAMERA_IN_USE

static val ERROR_CAMERA_IN_USE: Int

An error code that can be reported by onError indicating that the camera device is in use already.

This error can be produced when opening the camera fails due to the camera being used by a higher-priority camera API client.

Value: 1

ERROR_CAMERA_SERVICE

static val ERROR_CAMERA_SERVICE: Int

An error code that can be reported by onError indicating that the camera service has encountered a fatal error.

The Android device may need to be shut down and restarted to restore camera function, or there may be a persistent hardware problem.

An attempt at recovery may be possible by closing the CameraDevice and the CameraManager, and trying to acquire all resources again from scratch.

Value: 5

ERROR_MAX_CAMERAS_IN_USE

static val ERROR_MAX_CAMERAS_IN_USE: Int

An error code that can be reported by onError indicating that the camera device could not be opened because there are too many other open camera devices.

The system-wide limit for number of open cameras has been reached, and more camera devices cannot be opened until previous instances are closed.

This error can be produced when opening the camera fails.

Value: 2

onClosed

open fun onClosed(camera: CameraDevice): Unit

The method called when a camera device has been closed with CameraDevice.close.

Any attempt to call methods on this CameraDevice in the future will throw a IllegalStateException.

The default implementation of this method does nothing.

onDisconnected

abstract fun onDisconnected(camera: CameraDevice): Unit

The method called when a camera device is no longer available for use.

This callback may be called instead of onOpened if opening the camera fails.

Any attempt to call methods on this CameraDevice will throw a CameraAccessException. The disconnection could be due to a change in security policy or permissions; the physical disconnection of a removable camera device; or the camera being needed for a higher-priority camera API client.

There may still be capture callbacks that are invoked after this method is called, or new image buffers that are delivered to active outputs.

The default implementation logs a notice to the system log about the disconnection.

You should clean up the camera with CameraDevice.close after this happens, as it is not recoverable until the camera can be opened again. For most use cases, this will be when the camera again becomes available.

onError

abstract fun onError(
    camera: CameraDevice, 
    error: Int
): Unit

The method called when a camera device has encountered a serious error.

This callback may be called instead of onOpened if opening the camera fails.

This indicates a failure of the camera device or camera service in some way. Any attempt to call methods on this CameraDevice in the future will throw a CameraAccessException with the CAMERA_ERROR reason.

There may still be capture completion or camera stream callbacks that will be called after this error is received.

You should clean up the camera with CameraDevice.close after this happens. Further attempts at recovery are error-code specific.

onOpened

abstract fun onOpened(camera: CameraDevice): Unit

The method called when a camera device has finished opening.

At this point, the camera device is ready to use, and android.hardware.camera2.CameraDevice#createCaptureSession can be called to set up the first capture session.