txtView object not declared in the Barcode Dectector Setup

[laea51]

trafficstars

Hi, when trying to Compile the App, there was an error, that the txtView object was not defined, the App worked after I deleted the next code:

if(!detector.isOperational()){ txtView.setText("Could not set up the detector!"); return;

Nevertheless I believe that the feature is valid, but I couldn't declare the txtView object, so I removed the code. Maybe because I used an Android 5.1 lollipop version output.