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CameraManager.TorchCallback

public static abstract class CameraManager.TorchCallback
extends Object

java.lang.Object
   ↳ android.hardware.camera2.CameraManager.TorchCallback


A callback for camera flash torch modes becoming unavailable, disabled, or enabled.

The torch mode becomes unavailable when the camera device it belongs to becomes unavailable or other camera resources it needs become busy due to other higher priority camera activities. The torch mode becomes disabled when it was turned off or when the camera device it belongs to is no longer in use and other camera resources it needs are no longer busy. A camera's torch mode is turned off when an application calls CameraManager.setTorchMode(String, boolean) to turn off the camera's torch mode, or when an application turns on another camera's torch mode if keeping multiple torch modes on simultaneously is not supported. The torch mode becomes enabled when it is turned on via CameraManager.setTorchMode(String, boolean).

The torch mode is available to set via CameraManager.setTorchMode(String, boolean) only when it's in a disabled or enabled state.

Extend this callback and pass an instance of the subclass to CameraManager.registerTorchCallback(CameraManager.TorchCallback, Handler) to be notified of such status changes.

Summary

Public constructors

CameraManager.TorchCallback()

Public methods

void onTorchModeChanged(String cameraId, boolean enabled)

A camera's torch mode has become enabled or disabled and can be changed via CameraManager.setTorchMode(String, boolean).

void onTorchModeUnavailable(String cameraId)

A camera's torch mode has become unavailable to set via CameraManager.setTorchMode(String, boolean).

Inherited methods

Public constructors

CameraManager.TorchCallback

added in API level 23
public CameraManager.TorchCallback ()

Public methods

onTorchModeChanged

added in API level 23
public void onTorchModeChanged (String cameraId, 
                boolean enabled)

A camera's torch mode has become enabled or disabled and can be changed via CameraManager.setTorchMode(String, boolean).

The default implementation of this method does nothing.

Parameters
cameraId String: The unique identifier of the camera whose torch mode has been changed.

This value must never be null.

enabled boolean: The state that the torch mode of the camera has been changed to. true when the torch mode has become on and available to be turned off. false when the torch mode has becomes off and available to be turned on.

onTorchModeUnavailable

added in API level 23
public void onTorchModeUnavailable (String cameraId)

A camera's torch mode has become unavailable to set via CameraManager.setTorchMode(String, boolean).

If torch mode was previously turned on by calling CameraManager.setTorchMode(String, boolean), it will be turned off before onTorchModeUnavailable(String) is invoked. CameraManager.setTorchMode(String, boolean) will fail until the torch mode has entered a disabled or enabled state again.

The default implementation of this method does nothing.

Parameters
cameraId String: The unique identifier of the camera whose torch mode has become unavailable.

This value must never be null.