public
static
abstract
class
CameraDevice.StateCallback
extends Object
| java.lang.Object | |
| ↳ | android.hardware.camera2.CameraDevice.StateCallback |
A callback objects for receiving updates about the state of a camera device.
A callback instance must be provided to the openCamera(String, CameraDevice.StateCallback, Handler) method to
open a camera device.
These state updates include notifications about the device completing startup (
allowing for createCaptureSession(List to be called), about device
disconnection or closure, and about unexpected device errors.
Events about the progress of specific CaptureRequests are provided
through a CameraCaptureSession.CaptureCallback given to the
capture(CaptureRequest, CameraCaptureSession.CaptureCallback, Handler), captureBurst(List,
setRepeatingRequest(CaptureRequest, CameraCaptureSession.CaptureCallback, Handler), or
setRepeatingBurst(List methods.
Constants | |
|---|---|
int |
ERROR_CAMERA_DEVICE
An error code that can be reported by |
int |
ERROR_CAMERA_DISABLED
An error code that can be reported by |
int |
ERROR_CAMERA_IN_USE
An error code that can be reported by |
int |
ERROR_CAMERA_SERVICE
An error code that can be reported by |
int |
ERROR_MAX_CAMERAS_IN_USE
An error code that can be reported by |
Public constructors | |
|---|---|
CameraDevice.StateCallback()
|
|
Public methods | |
|---|---|
void
|
onClosed(CameraDevice camera)
The method called when a camera device has been closed with
|
abstract
void
|
onDisconnected(CameraDevice camera)
The method called when a camera device is no longer available for use. |
abstract
void
|
onError(CameraDevice camera, int error)
The method called when a camera device has encountered a serious error. |
abstract
void
|
onOpened(CameraDevice camera)
The method called when a camera device has finished opening. |
Inherited methods | |
|---|---|
 From
class
java.lang.Object
| |
int ERROR_CAMERA_DEVICE
An error code that can be reported by onError(CameraDevice, int)
indicating that the camera device has encountered a fatal error.
The camera device needs to be re-opened to be used again.
See also:
Constant Value: 4 (0x00000004)
int ERROR_CAMERA_DISABLED
An error code that can be reported by onError(CameraDevice, int)
indicating that the camera device could not be opened due to a device
policy.
Constant Value: 3 (0x00000003)
int ERROR_CAMERA_IN_USE
An error code that can be reported by onError(CameraDevice, int)
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.
See also:
Constant Value: 1 (0x00000001)
int ERROR_CAMERA_SERVICE
An error code that can be reported by onError(CameraDevice, int)
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.
See also:
Constant Value: 5 (0x00000005)
int ERROR_MAX_CAMERAS_IN_USE
An error code that can be reported by onError(CameraDevice, int)
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.
See also:
Constant Value: 2 (0x00000002)
void onClosed (CameraDevice camera)
The method called when a camera device has been closed with
close().
Any attempt to call methods on this CameraDevice in the
future will throw a IllegalStateException.
The default implementation of this method does nothing.
| Parameters | |
|---|---|
camera |
CameraDevice:
the camera device that has become closed
|
void onDisconnected (CameraDevice camera)
The method called when a camera device is no longer available for use.
This callback may be called instead of onOpened(CameraDevice)
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 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.
| Parameters | |
|---|---|
camera |
CameraDevice:
the device that has been disconnected
|
void onError (CameraDevice camera, int error)
The method called when a camera device has encountered a serious error.
This callback may be called instead of onOpened(CameraDevice)
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 close() after
this happens. Further attempts at recovery are error-code specific.
| Parameters | |
|---|---|
camera |
CameraDevice:
The device reporting the error |
error |
int:
The error code, one of the
StateCallback.ERROR_* values. |
void onOpened (CameraDevice camera)
The method called when a camera device has finished opening.
At this point, the camera device is ready to use, and
createCaptureSession(List can be called to set up the first capture
session.
| Parameters | |
|---|---|
camera |
CameraDevice:
the camera device that has become opened
|
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