// CONTROL_AE_STATE can be null on some devices

Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);

if (aeState == null ||

aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED) {

// CONTROL_AE_STATE can be null on some devices

Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);

if (aeState == null ||

aeState == CaptureResult.CONTROL_AE_STATE_PRECAPTURE ||

aeState == CaptureRequest.CONTROL_AE_STATE_FLASH_REQUIRED) {

// CONTROL_AE_STATE can be null on some devices

Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);

if (aeState == null || aeState != CaptureResult.CONTROL_AE_STATE_PRECAPTURE) {

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accept your pull requests.

1. Submit an issue describing your proposed change to the repo in question.

1. The repo owner will respond to your issue promptly.

1. If your proposed change is accepted, and you haven't already done so, sign a

Contributor License Agreement (see details above).

1. Fork the desired repo, develop and test your code changes.

1. Ensure that your code adheres to the existing style in the sample to which

you are contributing. Refer to the

[Android Code Style Guide]

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1. Submit a pull request.

This sample uses the following software:

Copyright 2014 The Android Open Source Project

Licensed under the Apache License, Version 2.0 (the "License");

you may not use this file except in compliance with the License.

You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software

distributed under the License is distributed on an "AS IS" BASIS,

WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

See the License for the specific language governing permissions and

limitations under the License.

This sample demonstrates how to use basic functionalities of Camera2

API. You can learn how to iterate through characteristics of all the

cameras attached to the device, display a camera preview, and take

pictures.

Introduction

The [Camera2 API][1] provides an interface to individual camera

devices connected to an Android device. It replaces the deprecated

Camera class.

Use [getCameraIdList][2] to get a list of all the available

cameras. You can then use [getCameraCharacteristics][3] and find the

best camera that suits your need (front/rear facing, resolution etc).

Create an instance of [CameraDevice.StateCallback][4] and open a

camera. It is ready to start camera preview when the camera is opened.

This sample uses TextureView to show the camera preview. Create a

[CameraCaptureSession][5] and set a repeating [CaptureRequest][6] to it.

Still image capture takes several steps. First, you need to lock the

focus of the camera by updating the CaptureRequest for the camera

preview. Then, in a similar way, you need to run a precapture

sequence. After that, it is ready to capture a picture. Create a new

CaptureRequest and call [capture][7]. Don't forget to unlock the focus

when you are done.

[1]: https://developer.android.com/reference/android/hardware/camera2/package-summary.html

[2]: https://developer.android.com/reference/android/hardware/camera2/CameraManager.html#getCameraIdList()

[3]: https://developer.android.com/reference/android/hardware/camera2/CameraManager.html#getCameraCharacteristics(java.lang.String)

[4]: https://developer.android.com/reference/android/hardware/camera2/CameraDevice.StateCallback.html

[5]: https://developer.android.com/reference/android/hardware/camera2/CameraCaptureSession.html

[6]: https://developer.android.com/reference/android/hardware/camera2/CaptureRequest.html

[7]: https://developer.android.com/reference/android/hardware/camera2/CameraCaptureSession.html#capture(android.hardware.camera2.CaptureRequest, android.hardware.camera2.CameraCaptureSession.CaptureCallback, android.os.Handler)

Screenshots

<img src="screenshots/main.png" height="400" alt="Screenshot"/>