CameraManager

getCameraCharacteristics

CameraCharacteristics getCameraCharacteristics (String cameraId)

Query the capabilities of a camera device. These capabilities are immutable for a given camera.

getCameraIdList

String[] getCameraIdList ()

Return the list of currently connected camera devices by identifier, including cameras that may be in use by other camera API clients.

Non-removable cameras use integers starting at 0 for their identifiers, while removable cameras have a unique identifier for each individual device, even if they are the same model.

openCamera

void openCamera (String cameraId, 
                CameraDevice.StateCallback callback, 
                Handler handler)

Open a connection to a camera with the given ID.

Use getCameraIdList() to get the list of available camera devices. Note that even if an id is listed, open may fail if the device is disconnected between the calls to getCameraIdList() and openCamera(String, CameraDevice.StateCallback, Handler), or if a higher-priority camera API client begins using the camera device.

As of API level 23, devices for which the onCameraUnavailable(String) callback has been called due to the device being in use by a lower-priority, background camera API client can still potentially be opened by calling this method when the calling camera API client has a higher priority than the current camera API client using this device. In general, if the top, foreground activity is running within your application process, your process will be given the highest priority when accessing the camera, and this method will succeed even if the camera device is in use by another camera API client. Any lower-priority application that loses control of the camera in this way will receive an onDisconnected(CameraDevice) callback.

Once the camera is successfully opened, onOpened(CameraDevice) will be invoked with the newly opened CameraDevice. The camera device can then be set up for operation by calling createCaptureSession(List, CameraCaptureSession.StateCallback, Handler) and createCaptureRequest(int)

If the camera becomes disconnected during initialization after this function call returns, onDisconnected(CameraDevice) with a CameraDevice in the disconnected state (and onOpened(CameraDevice) will be skipped).

If opening the camera device fails, then the device callback's onError method will be called, and subsequent calls on the camera device will throw a CameraAccessException.

registerAvailabilityCallback

void registerAvailabilityCallback (CameraManager.AvailabilityCallback callback, 
                Handler handler)

Register a callback to be notified about camera device availability.

Registering the same callback again will replace the handler with the new one provided.

The first time a callback is registered, it is immediately called with the availability status of all currently known camera devices.

onCameraUnavailable(String) will be called whenever a camera device is opened by any camera API client. As of API level 23, other camera API clients may still be able to open such a camera device, evicting the existing client if they have higher priority than the existing client of a camera device. See open() for more details.

Since this callback will be registered with the camera service, remember to unregister it once it is no longer needed; otherwise the callback will continue to receive events indefinitely and it may prevent other resources from being released. Specifically, the callbacks will be invoked independently of the general activity lifecycle and independently of the state of individual CameraManager instances.

registerTorchCallback

void registerTorchCallback (CameraManager.TorchCallback callback, 
                Handler handler)

Register a callback to be notified about torch mode status.

Registering the same callback again will replace the handler with the new one provided.

The first time a callback is registered, it is immediately called with the torch mode status of all currently known camera devices with a flash unit.

Since this callback will be registered with the camera service, remember to unregister it once it is no longer needed; otherwise the callback will continue to receive events indefinitely and it may prevent other resources from being released. Specifically, the callbacks will be invoked independently of the general activity lifecycle and independently of the state of individual CameraManager instances.

setTorchMode

void setTorchMode (String cameraId, 
                boolean enabled)

Set the flash unit's torch mode of the camera of the given ID without opening the camera device.

Use getCameraIdList() to get the list of available camera devices and use getCameraCharacteristics(String) to check whether the camera device has a flash unit. Note that even if a camera device has a flash unit, turning on the torch mode may fail if the camera device or other camera resources needed to turn on the torch mode are in use.

If setTorchMode(String, boolean) is called to turn on or off the torch mode successfully, onTorchModeChanged(String, boolean) will be invoked. However, even if turning on the torch mode is successful, the application does not have the exclusive ownership of the flash unit or the camera device. The torch mode will be turned off and becomes unavailable when the camera device that the flash unit belongs to becomes unavailable or when other camera resources to keep the torch on become unavailable ( onTorchModeUnavailable(String) will be invoked). Also, other applications are free to call setTorchMode(String, boolean) to turn off the torch mode ( onTorchModeChanged(String, boolean) will be invoked). If the latest application that turned on the torch mode exits, the torch mode will be turned off.

unregisterAvailabilityCallback

void unregisterAvailabilityCallback (CameraManager.AvailabilityCallback callback)

Remove a previously-added callback; the callback will no longer receive connection and disconnection callbacks.

Removing a callback that isn't registered has no effect.

unregisterTorchCallback

void unregisterTorchCallback (CameraManager.TorchCallback callback)

Remove a previously-added callback; the callback will no longer receive torch mode status callbacks.

Removing a callback that isn't registered has no effect.