Inflating the view before the camera permission is given and then starting the scanner after the permission is granted crashes

[Dima-369]

The sample app avoids this by only inflating the layout when the camera permission is given.

We are migrating this library into our project and this would allow us to quickly port everything without rewriting all the view logic.

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You can emulate this quickly by moving the line below from initQRCodeReaderView() to onCreate() while keeping the content variable as a class member variable:

View content = getLayoutInflater().inflate(R.layout.content_decoder, mainLayout, true);

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The sample app will then crash (after quickly displaying a single camera frame) with:

java.lang.RuntimeException: An error occurred while executing doInBackground()                                                                              
   at android.os.AsyncTask$3.done(AsyncTask.java:309)                                                                              
   at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)                                                                              
   at java.util.concurrent.FutureTask.setException(FutureTask.java:223)                                                                              
   at java.util.concurrent.FutureTask.run(FutureTask.java:242)                                                                              
   at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)                                                                              
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)                                                                              
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)                                                                              
   at java.lang.Thread.run(Thread.java:818)                                                                              
Caused by: java.lang.IllegalArgumentException: Both dimensions must be greater than 0                                                                              
   at com.google.zxing.common.BitMatrix.<init>(BitMatrix.java:50)                                                                              
   at com.google.zxing.common.GlobalHistogramBinarizer.getBlackMatrix(GlobalHistogramBinarizer.java:91)                                                                              
   at com.google.zxing.common.HybridBinarizer.getBlackMatrix(HybridBinarizer.java:86)                                                                              
   at com.google.zxing.BinaryBitmap.getBlackMatrix(BinaryBitmap.java:85)                                                                              
   at com.google.zxing.qrcode.QRCodeReader.decode(QRCodeReader.java:77)                                                                              
   at com.dlazaro66.qrcodereaderview.QRCodeReaderView$DecodeFrameTask.doInBackground(QRCodeReaderView.java:355)                                                                              
   at com.dlazaro66.qrcodereaderview.QRCodeReaderView$DecodeFrameTask.doInBackground(QRCodeReaderView.java:329)                                                                              
   at android.os.AsyncTask$2.call(AsyncTask.java:295)                                                                              
   at java.util.concurrent.FutureTask.run(FutureTask.java:237)                                                                              
   at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)                                                                               
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)                                                                               
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)                                                                               
   at java.lang.Thread.run(Thread.java:818)

[vietmobilefolk]

@Gira-X : Could you try use ViewStub as placeholder for QRCodeReaderView, then only inflate when permission granted?

[Dima-369]

Yes, that works indeed!

Here is the modified sample repo which uses a ViewStub: https://github.com/Gira-X/QRCodeReaderView

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But in the end we decided to use a Google Vision API view because it scans a bit faster: https://github.com/wax911/Vision-Barcode-Scanner