代码如下：
public class CameraTwoActivity extends AppCompatActivity implements TextureView.SurfaceTextureListener {
@Bind(R.id.textureview)
android.view.TextureView mPreviewView;
private Handler mHandler;
private HandlerThread mThreadHandler;
private Size mPreviewSize=null;
private CaptureRequest.Builder mPreviewBuilder;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.camera_activity);
ButterKnife.bind(this);
mThreadHandler = new HandlerThread("CAMERA2");
mThreadHandler.start();
mHandler = new Handler(mThreadHandler.getLooper());
mPreviewView.setSurfaceTextureListener(this);
}
@TargetApi(Build.VERSION_CODES.LOLLIPOP)
public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
try {
//获得CameraManager
CameraManager cameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
//获得属性
CameraCharacteristics characteristics = cameraManager.getCameraCharacteristics("0");
//支持的STREAM CONFIGURATION
StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
//显示的size
mPreviewSize = map.getOutputSizes(SurfaceTexture.class)[0];
//打开相机
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
cameraManager.openCamera("0", mCameraDeviceStateCallback, mHandler);
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {
}
@Override
public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
return false;
}
//TextureView.SurfaceTextureListener
@Override
public void onSurfaceTextureUpdated(SurfaceTexture surface) {
}
private CameraDevice.StateCallback mCameraDeviceStateCallback = new CameraDevice.StateCallback() {
@Override
public void onOpened(CameraDevice camera) {
try {
startPreview(camera);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
@Override
public void onDisconnected(CameraDevice camera) {
}
@Override
public void onError(CameraDevice camera, int error) {
}
};
//开始预览，主要是camera.createCaptureSession这段代码很重要，创建会话
private void startPreview(CameraDevice camera) throws CameraAccessException {
SurfaceTexture texture = mPreviewView.getSurfaceTexture();
texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight());
Surface surface = new Surface(texture);
Log.i(getClass().getName(),"1111");
try {
mPreviewBuilder = camera.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
} catch (CameraAccessException e) {
Log.i(getClass().getName(),"2222");
e.printStackTrace();
}
Log.i(getClass().getName(),"3333");
mPreviewBuilder.addTarget(surface);
camera.createCaptureSession(Arrays.asList(surface), mSessionStateCallback, mHandler);
}
private CameraCaptureSession.StateCallback mSessionStateCallback = new CameraCaptureSession.StateCallback() {
@Override
public void onConfigured(CameraCaptureSession session) {
try {
updatePreview(session);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
@Override
public void onConfigureFailed(CameraCaptureSession session) {
}
};
private void updatePreview(CameraCaptureSession session) throws CameraAccessException {
session.setRepeatingRequest(mPreviewBuilder.build(), null, mHandler);
}
}
