Question

我正在制作基于QR扫描程序的Android应用程序，它从QR码获取数据并发送到服务器检查数据，但我的扫描仪在扫描无效的QR码后卡住了

这是我的代码

Qrresult.java

 public class qrresult extends AppCompatActivity implements ZXingScannerView.ResultHandler {

    private ZXingScannerView mScannerView;
    private FocusHandler focusHandler;
    public ImageButton back;

public void backbut() {
    back = (ImageButton) findViewById(R.id.bckbut);
    back.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //onBackPressed();
            Intent back = new Intent(getApplicationContext(),mainmenu.class);
            startActivity(back);
        }
    });
     }

    @Override
    public void onCreate(Bundle state) {
        super.onCreate(state);
        setContentView(R.layout.activity_qrresult);
        RelativeLayout zscanner = (RelativeLayout) findViewById(R.id.zxscan);
        mScannerView = new ZXingScannerView(this);   // Programmatically initialize the scanner view

        focusHandler = new FocusHandler(new Handler(), mScannerView);
        zscanner.addView(mScannerView);
        backbut();

    }

@Override
public void onResume() {
    super.onResume();
    mScannerView.setResultHandler(this); // Register ourselves as a handler for scan results.
    mScannerView.setAutoFocus(false);
    mScannerView.startCamera();
    focusHandler.start();

}

@Override
public void onPause() {
    super.onPause();
    mScannerView.stopCamera();
    focusHandler.stop(); //Stop camera on pause
}
@Override
public void onStop(){
    super.onStop();
    mScannerView.stopCamera();
}
@Override
public void handleResult(Result rawResult) {
        // Do something with the result here
        String qrdata= rawResult.getText();
        qrresultWorker qrresultWorker= new qrresultWorker(this);
        qrresultWorker.execute(qrdata);
        //mScannerView.resumeCameraPreview(this);

        // If you would like to resume scanning, call this method below:
        //mScannerView.resumeCameraPreview(this);
    }
}

QrresultWorker.java

 public class qrresultWorker extends AsyncTask<String,Void,String> {



private Context context;
private AlertDialog alertDialog;
private ProgressDialog Asycdialog;
qrresultWorker(Context ctx) {
    context = ctx;
}

@Override
protected String doInBackground(String... params) {



   String login_url = "http://10.0.2.2/projects/dbcon1/qrresult.php";


        try {

            //Used for Sending data to Database

            String qrdata = params[0];
            URL url = new URL(login_url);
            HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
            httpURLConnection.setRequestMethod("POST");
            //httpURLConnection.setConnectTimeout(100000);
            //httpURLConnection.setReadTimeout(100000);
            httpURLConnection.setDoOutput(true);
            httpURLConnection.setDoInput(true);
            OutputStream outputStream = httpURLConnection.getOutputStream();
            BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
            String post_data = URLEncoder.encode("qrdata", "UTF-8") + "=" + URLEncoder.encode(qrdata, "UTF-8");
            bufferedWriter.write(post_data);
            bufferedWriter.flush();
            bufferedWriter.close();
            outputStream.close();

            //Used for Getting data from Database
            InputStream inputStream = httpURLConnection.getInputStream();
            BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "iso-8859-1"));
            String result = ""; //initializing with empty string
            String line = "";  //initializing with empty string
            while ((line = bufferedReader.readLine()) != null) {
                result += line;
            }
            bufferedReader.close();
            inputStream.close();
            httpURLConnection.disconnect();
            return result;
        } catch (IOException e) {
            e.printStackTrace();
        }

    return null;
}

@Override
protected void onPreExecute() {
    //progress dialog
    //Asycdialog = new ProgressDialog(context);
    //Asycdialog.setMessage("Scanning...");
    //Asycdialog.show();

    //alertdialog
    AlertDialog.Builder builder = new AlertDialog.Builder(context);
    builder.setPositiveButton("Cancel",
            new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog,
                                    int id) {
                    //Intent go = new Intent(context.getApplicationContext(),qrresult.class);
                    //context.startActivity(go);
                dialog.dismiss();

                }
           });
    alertDialog = builder.create();
    alertDialog.setTitle("Scan Status");
}

@Override
protected void onPostExecute(String result) {
    //Asycdialog.dismiss();

    /*String name = null;
    int balance = 0;
    String qrcode=null;
    JSONObject jsonResponse = null;
    try {
        jsonResponse = new JSONObject(result);
    } catch (JSONException e) {
        e.printStackTrace();
    }
*/
    if (result.equals("success")){

        Intent intent = new Intent(context.getApplicationContext(),sendmoney.class);
        context.startActivity(intent);

    }
    else {

        Toast.makeText(context.getApplicationContext(),"Coundn't scan the QR code",Toast.LENGTH_SHORT).show();
        //alertDialog.setMessage("Scanning Failed,Invalid Qrcode, please retry");
        //alertDialog.show();

    }


}

@Override
protected void onProgressUpdate(Void... values) {
    super.onProgressUpdate(values);
}

}

Answer 1

尝试设置仅扫描QR码以下代码的条件仅扫描QR码

只需在gradle中添加以下行，然后使用下面的代码

compile 'com.journeyapps:zxing-android-embedded:3.5.0'

使用以下代码扫描Qr代码

IntentIntegrator integrator = new IntentIntegrator(this);
  integrator.setDesiredBarcodeFormats(IntentIntegrator.QR_CODE_TYPES);
  integrator.setPrompt("Scan a barcode");
  integrator.setCameraId(0);  // Use a specific camera of the device
  integrator.setBeepEnabled(false);
  integrator.setBarcodeImageEnabled(true);
  integrator.initiateScan();

了解更多参考资料CLICK HERE

Answer 2

在处理完扫描数据后，您似乎错过了resumeCameraPreview(ZXingScannerView.ResultHandler resultHandler)上ZXingScannerView的来电。为此，您需要通知您的Activity在AsyncTask的onPostExecute方法中的扫描程序视图上调用该方法。由于您已在单独的类中实现了AsyncTask，因此您将不得不实现某种类似于以下内容的回调机制：What is the best way for AsyncTask to notify parent Activity about completion?。

Zxing Scanner跑了一次后卡住了吗？

2 个答案: