Camera: app passed NULL surface about qreader HOT 12 CLOSED

Let me look into it and update it here.

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@TonyTangAndroid are you setting the surface view as explained in the readme ? Also check if the sample app also throws the same error ?

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Yes. I was using the exact sample app that gets this error.

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@nisrulz +1 I am having the same issue. It occurs when I read a QRCode with a video a url, launch the intent to play the video and come back to the fragment that has the qrreader. Using Lollipop on Moto G 1st gen.

I call qrReader.stop before calling the intent, but that doesn't seem to be the problem. I'll come back with more details after some tests. Thanks.

[EDIT] Just executed some more tests, this seem to be happening when I am opening a new activity to play a video url:

Uri uri = Uri.parse(url); Intent i = new Intent(Intent.ACTION_VIEW, uri); startActivity(i);

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@nisrulz I might be having the same issue. The surface view turns black and doesn't update whenever the activity resumes. This happens with the sample app as well.

To replicate, simply leave the app by going to home, then resume the app.

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Hello sir ,i have the same issue as of Mr Joelclaudio.And i really need the solution.Please help.When i open the mail client by intent than on coming back to activity i m not able to scan and surface view shows black screen.Please help as soon as possible

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Ok I managed to find the problem and fix it.

When QReader.initAndStart() is called in onResume(), it adds a GlobalLayoutListener on surfaceView which calls QReader.start(). In here, it checks the boolean surfaceCreated and if it is false, it adds surfaceHolderCallback to the holder.

Now the issue is that surfaceHolderCallback removes itself from surfaceView when it is destroyed. It might be a change in the latest Android but when the view is rebuilt, the same surfaceView is used and re-created. The problem is that the re-adding of surfaceHolderCallback occurs after the surfaceView has been created, thus the surfaceCreated listener event is never called, resulting in the camera not starting.

The way to fix this is to not remove the callback when surfaceView is destroyed. This can be done by removing line 106 of QReader.java: surfaceHolder.removeCallback(this);

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It is read only because you are currently "linking" to the package in GitHub. What you need to do is clone the source out and then add it as a module to your project. Then you can edit the source.

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@pottiepie if you think that you have fixed the issue, could you send a PR. I haven't been able to pick the library code for sometime because of work.

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@pottiepie i did as per your instructions bt it gives me error on resuming that "Fail to connect to camera service".So help me in that

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Closing as issue is outdated. Please open a new issue if the issue still persists.

The library will be undergoing some maintenance soon.

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