private Semaphore mCameraOpenCloseLock = new Semaphore(1);//使用信号量 Semaphore 进行多线程任务调度
private Activity activity;
private File mFile;
private HandlerThread mBackgroundThread;
private Handler mBackgroundHandler;
private Size mPreviewSize;
private String mCameraId;
private CameraDevice mCameraDevice;
private CaptureRequest.Builder mPreviewRequestBuilder;
private CaptureRequest mPreviewRequest;
private CameraCaptureSession mCaptureSession;
private ImageReader mImageReader;
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);
}
public CameraPreview(Context context) {
this(context, null);
}
public CameraPreview(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public CameraPreview(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
mFile = new File(getContext().getExternalFilesDir(null), "pic.jpg");
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int width = MeasureSpec.getSize(widthMeasureSpec);
int height = MeasureSpec.getSize(heightMeasureSpec);
if (0 == mRatioWidth || 0 == mRatioHeight) {
setMeasuredDimension(width, height);
} else {
if (width < height * mRatioWidth / mRatioHeight) {
setMeasuredDimension(width, width * mRatioHeight / mRatioWidth);
} else {
setMeasuredDimension(height * mRatioWidth / mRatioHeight, height);
}
}
}
public void onResume(Activity activity) {
this.activity = activity;
startBackgroundThread();
//当Activity或Fragment OnResume()时,可以冲洗打开一个相机并开始预览,否则,这个Surface已经准备就绪
if (this.isAvailable()) {
openCamera(this.getWidth(), this.getHeight());
} else {
this.setSurfaceTextureListener(mSurfaceTextureListener);
}
}
public void onPause() {
closeCamera();
stopBackgroundThread();
}
public void setOutPutDir(File file) {
this.mFile = file;
}
public void setAspectRatio(int width, int height) {
