android - qrcode 扫描仪来自 zxing 的样本在扫描后没有返回到 onActivityResult

Question

我正在使用以下代码创建一个二维码扫描器，得到了一些引用 zxing 库的代码。整个代码工作正常，但是当扫描仪应用程序关闭时，它不会在完成 Activity 任务后调用 onActivityResult。有人可以帮我这是我正在使用的代码。

我的主要 Activity

/**
 * PhoneGap is available under *either* the terms of the modified BSD license *or* the
 * MIT License (2008). See http://opensource.org/licenses/alphabetical for full text.
 *
 * Copyright (c) Matt Kane 2010
 * Copyright (c) 2011, IBM Corporation
 * Copyright (c) 2013, Maciej Nux Jaros
 */


import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.content.Intent;
import android.util.Log;

import org.apache.cordova.CordovaPlugin;
import org.apache.cordova.CallbackContext;
import org.apache.cordova.LOG;
import org.apache.cordova.PluginResult;

import android.util.Log;
import android.widget.Toast;

/**
 * This calls out to the ZXing barcode reader and returns the result.
 *
 * @sa https://github.com/apache/cordova-android/blob/master/framework/src/org/apache/cordova/CordovaPlugin.java
 */
public class BarcodeScanner extends CordovaPlugin {
    public static final int REQUEST_CODE = 0x0ba7c0de;

    private static final String SCAN = "scan";
    private static final String ENCODE = "encode";
    private static final String CANCELLED = "cancelled";
    private static final String FORMAT = "format";
    private static final String TEXT = "text";
    private static final String DATA = "data";
    private static final String TYPE = "type";



    private static final String SCAN_INTENT = "com.google.zxing.client.android.SCAN";
    private static final String ENCODE_DATA = "ENCODE_DATA";
    private static final String ENCODE_TYPE = "ENCODE_TYPE";
    private static final String ENCODE_INTENT = "com.MobileApp.BarcodeScanner.ENCODE";
    private static final String TEXT_TYPE = "TEXT_TYPE";
    private static final String EMAIL_TYPE = "EMAIL_TYPE";
    private static final String PHONE_TYPE = "PHONE_TYPE";
    private static final String SMS_TYPE = "SMS_TYPE";

    private static final String LOG_TAG = "BarcodeScanner";

    private CallbackContext callbackContext;

    /**
     * Constructor.
     */
    public BarcodeScanner() {
    }

    /**
     * Executes the request.
     *
     * This method is called from the WebView thread. To do a non-trivial amount of work, use:
     *     cordova.getThreadPool().execute(runnable);
     *
     * To run on the UI thread, use:
     *     cordova.getActivity().runOnUiThread(runnable);
     *
     * @param action          The action to execute.
     * @param args            The exec() arguments.
     * @param callbackContext The callback context used when calling back into JavaScript.
     * @return                Whether the action was valid.
     *
     * @sa https://github.com/apache/cordova-android/blob/master/framework/src/org/apache/cordova/CordovaPlugin.java
     */
    @Override
    public boolean execute(String action, JSONArray args, CallbackContext callbackContext) {
        this.callbackContext = callbackContext;

        if (action.equals(ENCODE)) {
            JSONObject obj = args.optJSONObject(0);
            if (obj != null) {
                String type = obj.optString(TYPE);
                String data = obj.optString(DATA);

                // If the type is null then force the type to text
                if (type == null) {
                    type = TEXT_TYPE;
                }

                if (data == null) {
                    callbackContext.error("User did not specify data to encode");
                    return true;
                }

//                encode(type, data);

            } else {
                callbackContext.error("User did not specify data to encode");
                return true;
            }
        } else if (action.equals(SCAN)) {
            scan(args);
        } else {
            return false;
        }
        return true;
    }

    /**
     * Starts an intent to scan and decode a barcode.
     */
    public void scan(JSONArray args) {



        IntentIntegrator integrator = new IntentIntegrator(this.cordova.getActivity());
        integrator.initiateScan(); 


    }



    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        // TODO Auto-generated method stub
            String contantsString = null;
            IntentResult scanResult = IntentIntegrator.parseActivityResult(
                requestCode, resultCode, data);
            JSONObject obj = new JSONObject();
        if (scanResult != null) 
        {

            // handle scan result
            contantsString = scanResult.getContents() == null ? "0"
                    : scanResult.getContents();
            if (contantsString.equalsIgnoreCase("0")) 
                {
//                  Toast.makeText(this.cordova.getActivity(),
//                          "Problem to get the  contant Number", Toast.LENGTH_LONG)
//                          .show();
                Log.d(LOG_TAG, "Problem in reading the result possibly read string is 0");
                } 
            else 
                {
//                  Toast.makeText(this.cordova.getActivity(), contantsString,
//                      Toast.LENGTH_LONG).show();
                Log.d(LOG_TAG, "succesfully read the barcode");

                }

            try {
                obj.put(TEXT, contantsString);
                obj.put(FORMAT, contantsString);
                obj.put(CANCELLED, false);
            } catch (JSONException e) {
                Log.d(LOG_TAG, "This should never happen");
            }
        } else {
//                  Toast.makeText(this.cordova.getActivity(),
//                          "Problem to scan the barcode.", Toast.LENGTH_LONG).show();
            Log.d(LOG_TAG, "Problem in reading the result possibly read string is null");
                        try 
                        {
                            obj.put(TEXT, "");
                            obj.put(FORMAT, "");
                            obj.put(CANCELLED, false);
                        }
                        catch (JSONException e) {
                            Log.d(LOG_TAG, "This should never happen");
                        }
                }
    }



  }

IntentIntegrator 类

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.ActivityNotFoundException;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.net.Uri;
import android.util.Log;


public final class IntentIntegrator {

  public static final int REQUEST_CODE = 0x0000c0de; // Only use bottom 16 bits
  private static final String TAG = IntentIntegrator.class.getSimpleName();

  public static final String DEFAULT_TITLE = "Install Barcode Scanner?";
  public static final String DEFAULT_MESSAGE =
      "This application requires Barcode Scanner. Would you like to install it?";
  public static final String DEFAULT_YES = "Yes";
  public static final String DEFAULT_NO = "No";

  private static final String BS_PACKAGE = "com.google.zxing.client.android";

  // supported barcode formats
  public static final Collection<String> PRODUCT_CODE_TYPES = list("UPC_A", "UPC_E", "EAN_8", "EAN_13", "RSS_14");
  public static final Collection<String> ONE_D_CODE_TYPES =
      list("UPC_A", "UPC_E", "EAN_8", "EAN_13", "CODE_39", "CODE_93", "CODE_128",
           "ITF", "RSS_14", "RSS_EXPANDED");
  public static final Collection<String> QR_CODE_TYPES = Collections.singleton("QR_CODE");
  public static final Collection<String> DATA_MATRIX_TYPES = Collections.singleton("DATA_MATRIX");

  public static final Collection<String> ALL_CODE_TYPES = null;

  public static final Collection<String> TARGET_BARCODE_SCANNER_ONLY = Collections.singleton(BS_PACKAGE);
  public static final Collection<String> TARGET_ALL_KNOWN = list(
          BS_PACKAGE, // Barcode Scanner
          "com.srowen.bs.android", // Barcode Scanner+
          "com.srowen.bs.android.simple" // Barcode Scanner+ Simple
          // TODO add more -- what else supports this intent?
      );

  private final Activity activity;
  private String title;
  private String message;
  private String buttonYes;
  private String buttonNo;
  private Collection<String> targetApplications;

  public IntentIntegrator(Activity activity) {
    this.activity = activity;
    title = DEFAULT_TITLE;
    message = DEFAULT_MESSAGE;
    buttonYes = DEFAULT_YES;
    buttonNo = DEFAULT_NO;
    targetApplications = TARGET_ALL_KNOWN;
  }

  public String getTitle() {
    return title;
  }

  public void setTitle(String title) {
    this.title = title;
  }

  public void setTitleByID(int titleID) {
    title = activity.getString(titleID);
  }

  public String getMessage() {
    return message;
  }

  public void setMessage(String message) {
    this.message = message;
  }

  public void setMessageByID(int messageID) {
    message = activity.getString(messageID);
  }

  public String getButtonYes() {
    return buttonYes;
  }

  public void setButtonYes(String buttonYes) {
    this.buttonYes = buttonYes;
  }

  public void setButtonYesByID(int buttonYesID) {
    buttonYes = activity.getString(buttonYesID);
  }

  public String getButtonNo() {
    return buttonNo;
  }

  public void setButtonNo(String buttonNo) {
    this.buttonNo = buttonNo;
  }

  public void setButtonNoByID(int buttonNoID) {
    buttonNo = activity.getString(buttonNoID);
  }

  public Collection<String> getTargetApplications() {
    return targetApplications;
  }

  public void setTargetApplications(Collection<String> targetApplications) {
    this.targetApplications = targetApplications;
  }

  public void setSingleTargetApplication(String targetApplication) {
    this.targetApplications = Collections.singleton(targetApplication);
  }

  /**
   * Initiates a scan for all known barcode types.
   */
  public AlertDialog initiateScan() {
    return initiateScan(ALL_CODE_TYPES);
  }

  /**
   * Initiates a scan only for a certain set of barcode types, given as strings corresponding
   * to their names in ZXing's {@code BarcodeFormat} class like "UPC_A". You can supply constants
   * like {@link #PRODUCT_CODE_TYPES} for example.
   */
  public AlertDialog initiateScan(Collection<String> desiredBarcodeFormats) {
    Intent intentScan = new Intent(BS_PACKAGE + ".SCAN");
    intentScan.addCategory(Intent.CATEGORY_DEFAULT);

    // check which types of codes to scan for
    if (desiredBarcodeFormats != null) {
      // set the desired barcode types
      StringBuilder joinedByComma = new StringBuilder();
      for (String format : desiredBarcodeFormats) {
        if (joinedByComma.length() > 0) {
          joinedByComma.append(',');
        }
        joinedByComma.append(format);
      }
      intentScan.putExtra("SCAN_FORMATS", joinedByComma.toString());
    }

    String targetAppPackage = findTargetAppPackage(intentScan);
    if (targetAppPackage == null) {
      return showDownloadDialog();
    }
    intentScan.setPackage(targetAppPackage);
    intentScan.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    intentScan.addFlags(Intent.FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET);
    activity.startActivityForResult(intentScan, REQUEST_CODE);
    return null;
  }

  private String findTargetAppPackage(Intent intent) {
    PackageManager pm = activity.getPackageManager();
    List<ResolveInfo> availableApps = pm.queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
    if (availableApps != null) {
      for (ResolveInfo availableApp : availableApps) {
        String packageName = availableApp.activityInfo.packageName;
        if (targetApplications.contains(packageName)) {
          return packageName;
        }
      }
    }
    return null;
  }

  private AlertDialog showDownloadDialog() {
    AlertDialog.Builder downloadDialog = new AlertDialog.Builder(activity);
    downloadDialog.setTitle(title);
    downloadDialog.setMessage(message);
    downloadDialog.setPositiveButton(buttonYes, new DialogInterface.OnClickListener() {
      @Override
      public void onClick(DialogInterface dialogInterface, int i) {
        Uri uri = Uri.parse("market://details?id=" + BS_PACKAGE);
        Intent intent = new Intent(Intent.ACTION_VIEW, uri);
        try {
          activity.startActivity(intent);
        } catch (ActivityNotFoundException anfe) {
          // Hmm, market is not installed
          Log.w(TAG, "Android Market is not installed; cannot install Barcode Scanner");
        }
      }
    });
    downloadDialog.setNegativeButton(buttonNo, new DialogInterface.OnClickListener() {
      @Override
      public void onClick(DialogInterface dialogInterface, int i) {}
    });
    return downloadDialog.show();
  }


  /**
   * <p>Call this from your {@link Activity}'s
   * {@link Activity#onActivityResult(int, int, Intent)} method.</p>
   *
   * @return null if the event handled here was not related to this class, or
   *  else an {@link IntentResult} containing the result of the scan. If the user cancelled scanning,
   *  the fields will be null.
   */
  public static IntentResult parseActivityResult(int requestCode, int resultCode, Intent intent) {
    if (requestCode == REQUEST_CODE) {
      if (resultCode == Activity.RESULT_OK) {
        String contents = intent.getStringExtra("SCAN_RESULT");
        String formatName = intent.getStringExtra("SCAN_RESULT_FORMAT");
        byte[] rawBytes = intent.getByteArrayExtra("SCAN_RESULT_BYTES");
        int intentOrientation = intent.getIntExtra("SCAN_RESULT_ORIENTATION", Integer.MIN_VALUE);
        Integer orientation = intentOrientation == Integer.MIN_VALUE ? null : intentOrientation;
        String errorCorrectionLevel = intent.getStringExtra("SCAN_RESULT_ERROR_CORRECTION_LEVEL");
        return new IntentResult(contents,
                                formatName,
                                rawBytes,
                                orientation,
                                errorCorrectionLevel);
      }
      return new IntentResult();
    }
    return null;
  }


  /**
   * Shares the given text by encoding it as a barcode, such that another user can
   * scan the text off the screen of the device.
   *
   * @param text the text string to encode as a barcode
   */
  public void shareText(CharSequence text) {
    Intent intent = new Intent();
    intent.addCategory(Intent.CATEGORY_DEFAULT);
    intent.setAction(BS_PACKAGE + ".ENCODE");
    intent.putExtra("ENCODE_TYPE", "TEXT_TYPE");
    intent.putExtra("ENCODE_DATA", text);
    String targetAppPackage = findTargetAppPackage(intent);
    if (targetAppPackage == null) {
      showDownloadDialog();
    } else {
      intent.setPackage(targetAppPackage);
      intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
      intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET);
      activity.startActivity(intent);
    }
  }

  private static Collection<String> list(String... values) {
    return Collections.unmodifiableCollection(Arrays.asList(values));
  }

}

IntentResult 类

public final class IntentResult {

    private final String contents;
    private final String formatName;
    private final byte[] rawBytes;
    private final Integer orientation;
    private final String errorCorrectionLevel;

    IntentResult() {
      this(null, null, null, null, null);
    }

    IntentResult(String contents,
                 String formatName,
                 byte[] rawBytes,
                 Integer orientation,
                 String errorCorrectionLevel) {
      this.contents = contents;
      this.formatName = formatName;
      this.rawBytes = rawBytes;
      this.orientation = orientation;
      this.errorCorrectionLevel = errorCorrectionLevel;
    }

    /**
     * @return raw content of barcode
     */
    public String getContents() {
      return contents;
    }

    /**
     * @return name of format, like "QR_CODE", "UPC_A". See {@code BarcodeFormat} for more format names.
     */
    public String getFormatName() {
      return formatName;
    }

    /**
     * @return raw bytes of the barcode content, if applicable, or null otherwise
     */
    public byte[] getRawBytes() {
      return rawBytes;
    }

    /**
     * @return rotation of the image, in degrees, which resulted in a successful scan. May be null.
     */
    public Integer getOrientation() {
      return orientation;
    }

    /**
     * @return name of the error correction level used in the barcode, if applicable
     */
    public String getErrorCorrectionLevel() {
      return errorCorrectionLevel;
    }

    @Override
    public String toString() {
      StringBuilder dialogText = new StringBuilder(100);
      dialogText.append("Format: ").append(formatName).append('\n');
      dialogText.append("Contents: ").append(contents).append('\n');
      int rawBytesLength = rawBytes == null ? 0 : rawBytes.length;
      dialogText.append("Raw bytes: (").append(rawBytesLength).append(" bytes)\n");
      dialogText.append("Orientation: ").append(orientation).append('\n');
      dialogText.append("EC level: ").append(errorCorrectionLevel).append('\n');
      return dialogText.toString();
    }

  }

应用打开，但当它扫描二维码时没有返回任何内容。

Answer 1

这段代码对我有用……我破坏了上面的代码并将其用于我的代码并且它起作用了。

/**
 * PhoneGap is available under *either* the terms of the modified BSD license *or* the
 * MIT License (2008). See http://opensource.org/licenses/alphabetical for full text.
 *
 * Copyright (c) Matt Kane 2010
 * Copyright (c) 2011, IBM Corporation
 * Copyright (c) 2013, Maciej Nux Jaros
 */


import java.util.List;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.ActivityNotFoundException;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.net.Uri;
import android.util.Log;

import org.apache.cordova.CordovaPlugin;
import org.apache.cordova.CallbackContext;
import org.apache.cordova.PluginResult;

/**
 * This calls out to the ZXing barcode reader and returns the result.
 *
 * @sa https://github.com/apache/cordova-android/blob/master/framework/src/org/apache/cordova/CordovaPlugin.java
 */
public class BarcodeScanner extends CordovaPlugin {
    public static final int REQUEST_CODE = 0x0ba7c0de;

    private static final String SCAN = "scan";
    private static final String ENCODE = "encode";
    private static final String CANCELLED = "cancelled";
    private static final String FORMAT = "format";
    private static final String TEXT = "text";
    private static final String DATA = "data";
    private static final String TYPE = "type";
    private static final String SCAN_INTENT = "com.google.zxing.client.android";
    private static final String ENCODE_DATA = "ENCODE_DATA";
    private static final String ENCODE_TYPE = "ENCODE_TYPE";
    private static final String ENCODE_INTENT = "com.phonegap.plugins.barcodescanner.ENCODE";
    private static final String TEXT_TYPE = "TEXT_TYPE";
    private static final String EMAIL_TYPE = "EMAIL_TYPE";
    private static final String PHONE_TYPE = "PHONE_TYPE";
    private static final String SMS_TYPE = "SMS_TYPE";

    private static final String LOG_TAG = "BarcodeScanner";

    private CallbackContext callbackContext;

    /**
     * Constructor.
     */
    public BarcodeScanner() {
    }

    /**
     * Executes the request.
     *
     * This method is called from the WebView thread. To do a non-trivial amount of work, use:
     *     cordova.getThreadPool().execute(runnable);
     *
     * To run on the UI thread, use:
     *     cordova.getActivity().runOnUiThread(runnable);
     *
     * @param action          The action to execute.
     * @param args            The exec() arguments.
     * @param callbackContext The callback context used when calling back into JavaScript.
     * @return                Whether the action was valid.
     *
     * @sa https://github.com/apache/cordova-android/blob/master/framework/src/org/apache/cordova/CordovaPlugin.java
     */
    @Override
    public boolean execute(String action, JSONArray args, CallbackContext callbackContext) {
        this.callbackContext = callbackContext;

        if (action.equals(ENCODE)) {
            JSONObject obj = args.optJSONObject(0);
            if (obj != null) {
                String type = obj.optString(TYPE);
                String data = obj.optString(DATA);

                // If the type is null then force the type to text
                if (type == null) {
                    type = TEXT_TYPE;
                }

                if (data == null) {
                    callbackContext.error("User did not specify data to encode");
                    return true;
                }

                encode(type, data);
            } else {
                callbackContext.error("User did not specify data to encode");
                return true;
            }
        } else if (action.equals(SCAN)) {
            scan();
        } else {
            return false;
        }
        return true;
    }

    /**
     * Starts an intent to scan and decode a barcode.
     */
    public AlertDialog scan() {
        Intent intentScan = new Intent(SCAN_INTENT+".SCAN");
        intentScan.addCategory(Intent.CATEGORY_DEFAULT);

        String targetAppPackage = findTargetAppPackage(intentScan);
        if (targetAppPackage == null) {
          return showDownloadDialog();
        }



        this.cordova.startActivityForResult((CordovaPlugin) this, intentScan, REQUEST_CODE);
        return null;
    }

    private String findTargetAppPackage(Intent intent) {
        PackageManager pm = this.cordova.getActivity().getPackageManager();
        List<ResolveInfo> availableApps = pm.queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
        if (availableApps != null) {
          for (ResolveInfo availableApp : availableApps) {
            String packageName = availableApp.activityInfo.packageName;
//            if (targetApplications.contains(packageName)) {
//              return packageName;
//            }

            if (packageName!=null) {
                return packageName;
              }
          }
        }
        return null;
      }

    private AlertDialog showDownloadDialog() {
        AlertDialog.Builder downloadDialog = new AlertDialog.Builder(BarcodeScanner.this.cordova.getActivity());
        downloadDialog.setTitle("Install Barcode Scanner?");
        downloadDialog.setMessage("This application requires Barcode Scanner. Would you like to install it?");
        downloadDialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
          @Override
          public void onClick(DialogInterface dialogInterface, int i) {
            Uri uri = Uri.parse("market://details?id=" + SCAN_INTENT);
            Intent intent = new Intent(Intent.ACTION_VIEW, uri);
            try {
                BarcodeScanner.this.cordova.getActivity().startActivity(intent);
            } catch (ActivityNotFoundException anfe) {
              // Hmm, market is not installed
//              Log.w(TAG, "Android Market is not installed; cannot install Barcode Scanner");
            }
          }
        });
        downloadDialog.setNegativeButton("No", new DialogInterface.OnClickListener() {
          @Override
          public void onClick(DialogInterface dialogInterface, int i) {}
        });
        return downloadDialog.show();
      }

    /**
     * Called when the barcode scanner intent completes.
     *
     * @param requestCode The request code originally supplied to startActivityForResult(),
     *                       allowing you to identify who this result came from.
     * @param resultCode  The integer result code returned by the child activity through its setResult().
     * @param intent      An Intent, which can return result data to the caller (various data can be attached to Intent "extras").
     */
    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent intent) {
        if (requestCode == REQUEST_CODE) {
            if (resultCode == Activity.RESULT_OK) {
                JSONObject obj = new JSONObject();
                try {
                    obj.put(TEXT, intent.getStringExtra("SCAN_RESULT"));
                    obj.put(FORMAT, intent.getStringExtra("SCAN_RESULT_FORMAT"));
                    obj.put(CANCELLED, false);
                } catch (JSONException e) {
                    Log.d(LOG_TAG, "This should never happen");
                }
                //this.success(new PluginResult(PluginResult.Status.OK, obj), this.callback);
                this.callbackContext.success(obj);
            } else if (resultCode == Activity.RESULT_CANCELED) {
                JSONObject obj = new JSONObject();
                try {
                    obj.put(TEXT, "");
                    obj.put(FORMAT, "");
                    obj.put(CANCELLED, true);
                } catch (JSONException e) {
                    Log.d(LOG_TAG, "This should never happen");
                }
                //this.success(new PluginResult(PluginResult.Status.OK, obj), this.callback);
                this.callbackContext.success(obj);
            } else {
                //this.error(new PluginResult(PluginResult.Status.ERROR), this.callback);
                this.callbackContext.error("Unexpected error");
            }
        }
    }

    /**
     * Initiates a barcode encode.
     *
     * @param type Endoiding type.
     * @param data The data to encode in the bar code.
     */
    public void encode(String type, String data) {
        Intent intentEncode = new Intent(ENCODE_INTENT);
        intentEncode.putExtra(ENCODE_TYPE, type);
        intentEncode.putExtra(ENCODE_DATA, data);

        this.cordova.getActivity().startActivity(intentEncode);
    }
}