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activity_main.xml

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MainActivity

import android.Manifest;import android.app.Activity;import android.content.Context;import android.content.pm.PackageManager;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.ImageFormat;import android.hardware.camera2.CameraAccessException;import android.hardware.camera2.CameraCaptureSession;import android.hardware.camera2.CameraCharacteristics;import android.hardware.camera2.CameraDevice;import android.hardware.camera2.CameraManager;import android.hardware.camera2.CaptureRequest;import android.media.Image;import android.media.ImageReader;import android.os.Build;import android.os.Bundle;import android.os.Handler;import android.os.HandlerThread;import android.support.annotation.RequiresApi;import android.support.v4.app.ActivityCompat;import android.util.SparseIntArray;import android.view.Surface;import android.view.SurfaceHolder;import android.view.SurfaceView;import android.view.View;import android.widget.ImageView;import android.widget.Toast;import java.nio.ByteBuffer;import java.util.Arrays;public class MainActivity extends Activity implements View.OnClickListener {    private static final SparseIntArray ORIENTATIONS = new SparseIntArray();    ///为了使照片竖直显示    static {        ORIENTATIONS.append(Surface.ROTATION_0, 90);        ORIENTATIONS.append(Surface.ROTATION_90, 0);        ORIENTATIONS.append(Surface.ROTATION_180, 270);        ORIENTATIONS.append(Surface.ROTATION_270, 180);    }    private SurfaceView mSurfaceView;    private SurfaceHolder mSurfaceHolder;    private ImageView iv_show;    private CameraManager mCameraManager;//摄像头管理器    private Handler childHandler, mainHandler;    private String mCameraID;//摄像头Id 0 为后  1 为前    private ImageReader mImageReader;    private CameraCaptureSession mCameraCaptureSession;    private CameraDevice mCameraDevice;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initVIew();    }    /**     * 初始化     */    private void initVIew() {        iv_show = (ImageView) findViewById(R.id.iv_show_camera2_activity);        //mSurfaceView        mSurfaceView = (SurfaceView) findViewById(R.id.surface_view_camera2_activity);        mSurfaceView.setOnClickListener(this);        mSurfaceHolder = mSurfaceView.getHolder();        mSurfaceHolder.setKeepScreenOn(true);        // mSurfaceView添加回调        mSurfaceHolder.addCallback(new SurfaceHolder.Callback() {            @Override            public void surfaceCreated(SurfaceHolder holder) { //SurfaceView创建                // 初始化Camera                initCamera2();            }            @Override            public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {            }            @Override            public void surfaceDestroyed(SurfaceHolder holder) { //SurfaceView销毁                // 释放Camera资源                if (null != mCameraDevice) {                    mCameraDevice.close();                    MainActivity.this.mCameraDevice = null;                }            }        });    }    /**     * 初始化Camera2     */    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)    private void initCamera2() {        HandlerThread handlerThread = new HandlerThread("Camera2");        handlerThread.start();        childHandler = new Handler(handlerThread.getLooper());        mainHandler = new Handler(getMainLooper());        mCameraID = "" + CameraCharacteristics.LENS_FACING_FRONT;//前摄像头        mImageReader = ImageReader.newInstance(1080, 1920, ImageFormat.JPEG,1);        mImageReader.setOnImageAvailableListener(new ImageReader.OnImageAvailableListener() { //可以在这里处理拍照得到的临时照片 例如，写入本地            @Override            public void onImageAvailable(ImageReader reader) {                mCameraDevice.close();                mSurfaceView.setVisibility(View.GONE);                iv_show.setVisibility(View.VISIBLE);                // 拿到拍照照片数据                Image image = reader.acquireNextImage();                ByteBuffer buffer = image.getPlanes()[0].getBuffer();                byte[] bytes = new byte[buffer.remaining()];                buffer.get(bytes);//由缓冲区存入字节数组                final Bitmap bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);                if (bitmap != null) {                    iv_show.setImageBitmap(bitmap);                }            }        }, mainHandler);        //获取摄像头管理        mCameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);        try {            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {                return;            }            //打开摄像头            mCameraManager.openCamera(mCameraID, stateCallback, mainHandler);        } catch (CameraAccessException e) {            e.printStackTrace();        }    }    /**     * 摄像头创建监听     */    private CameraDevice.StateCallback stateCallback = new CameraDevice.StateCallback() {        @Override        public void onOpened(CameraDevice camera) {//打开摄像头            mCameraDevice = camera;            //开启预览            takePreview();        }        @Override        public void onDisconnected(CameraDevice camera) {//关闭摄像头            if (null != mCameraDevice) {                mCameraDevice.close();                MainActivity.this.mCameraDevice = null;            }        }        @Override        public void onError(CameraDevice camera, int error) {//发生错误            Toast.makeText(MainActivity.this, "摄像头开启失败", Toast.LENGTH_SHORT).show();        }    };    /**     * 开始预览     */    private void takePreview() {        try {            // 创建预览需要的CaptureRequest.Builder            final CaptureRequest.Builder previewRequestBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);            // 将SurfaceView的surface作为CaptureRequest.Builder的目标            previewRequestBuilder.addTarget(mSurfaceHolder.getSurface());            // 创建CameraCaptureSession，该对象负责管理处理预览请求和拍照请求            mCameraDevice.createCaptureSession(Arrays.asList(mSurfaceHolder.getSurface(), mImageReader.getSurface()), new CameraCaptureSession.StateCallback() // ③            {                @Override                public void onConfigured(CameraCaptureSession cameraCaptureSession) {                    if (null == mCameraDevice) return;                    // 当摄像头已经准备好时，开始显示预览                    mCameraCaptureSession = cameraCaptureSession;                    try {                        // 自动对焦                        previewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);                        // 打开闪光灯                        previewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH);                        // 显示预览                        CaptureRequest previewRequest = previewRequestBuilder.build();                        mCameraCaptureSession.setRepeatingRequest(previewRequest, null, childHandler);                    } catch (CameraAccessException e) {                        e.printStackTrace();                    }                }                @Override                public void onConfigureFailed(CameraCaptureSession cameraCaptureSession) {                    Toast.makeText(MainActivity.this, "配置失败", Toast.LENGTH_SHORT).show();                }            }, childHandler);        } catch (CameraAccessException e) {            e.printStackTrace();        }    }    /**     * 点击事件     */    @Override    public void onClick(View v) {        takePicture();    }    /**     * 拍照     */    private void takePicture() {        if (mCameraDevice == null) return;        // 创建拍照需要的CaptureRequest.Builder        final CaptureRequest.Builder captureRequestBuilder;        try {            captureRequestBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);            // 将imageReader的surface作为CaptureRequest.Builder的目标            captureRequestBuilder.addTarget(mImageReader.getSurface());            // 自动对焦            captureRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);            // 自动曝光            captureRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH);            // 获取手机方向            int rotation = getWindowManager().getDefaultDisplay().getRotation();            // 根据设备方向计算设置照片的方向            captureRequestBuilder.set(CaptureRequest.JPEG_ORIENTATION, ORIENTATIONS.get(rotation));            //拍照            CaptureRequest mCaptureRequest = captureRequestBuilder.build();            mCameraCaptureSession.capture(mCaptureRequest, null, childHandler);        } catch (CameraAccessException e) {            e.printStackTrace();        }    }    //开始播放    public void start() {        try {            Log.e(tag,"start");            mCameraCaptureSession.setRepeatingRequest(mCaptureRequestBuilder.build(), null, childHandler);        } catch (CameraAccessException e) {            e.printStackTrace();        }    }    //暂停播放    public void stop() {        try {            Log.e(tag,"stop");            mCameraCaptureSession.stopRepeating();        } catch (CameraAccessException e) {            e.printStackTrace();        }    }    //关闭播放    public void close() {        if (mTextureView != null) {            mTextureView = null;        }        // mPreviewed=false;        if (childHandler != null) {            childHandler.removeCallbacksAndMessages(null);            childHandler = null;        }        if (mHandler != null)            mHandler.removeCallbacksAndMessages(null);        mHandler = null;        if (mHandlerThread != null) {            mHandlerThread.quit();            mHandlerThread = null;        }        if (null != mCameraCaptureSession) {            mCameraCaptureSession.close();            mCameraCaptureSession = null;        }        if (null != mCameraDevice) {            mCameraDevice.close();            mCameraDevice = null;        }        if (null != mImageReader) {            mImageReader.close();            mImageReader = null;        }    }}

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