当屏幕关闭时，背景中的相机预览会出错

Question

基于GoogleSamples编写代码，并更改一些内容以在后台预览，而不是在示例代码中拍照。

例如：

@Override
public void onResume() {
super.onResume();
/*startBackgroundThread();
// When the screen is turned off and turned back on, the SurfaceTexture is already
// available, and "onSurfaceTextureAvailable" will not be called. In that case, we can open
// a camera and start preview from here (otherwise, we wait until the surface is ready in
// the SurfaceTextureListener).
if (mTextureView.isAvailable()) {
openCamera(mTextureView.getWidth(), mTextureView.getHeight());
} else {
mTextureView.setSurfaceTextureListener(mSurfaceTextureListener);
}*/
}
@Override
public void onPause() {
/*closeCamera();
stopBackgroundThread();*/
super.onPause();
}
public synchronized void start() {
if (mCameraDevice != null) {
return;
}
startBackgroundThread();
// When the screen is turned off and turned back on, the SurfaceTexture is already
// available, and "onSurfaceTextureAvailable" will not be called. In that case, we can open
// a camera and start preview from here (otherwise, we wait until the surface is ready in
// the SurfaceTextureListener).
if (mTextureView.isAvailable()) {
openCamera(mTextureView.getWidth(), mTextureView.getHeight());
} else {
mTextureView.setSurfaceTextureListener(mSurfaceTextureListener);
}
}
public synchronized void stop() {
if (mCameraDevice == null) {
return;
}
closeCamera();
stopBackgroundThread();
}

但是，当屏幕关闭一分钟时，相机预览会出现错误：在此处输入图像描述在此处输入图像描述

为什么以及如何避免？

Answer 1

startForegroundService(new Intent(this，EmptyService.class((；

活动中需要一个前台服务，然后一切正常。