A utility class which helps ease integration with Barcode Scanner via {@link Intent}s. This is a simple + * way to invoke barcode scanning and receive the result, without any need to integrate, modify, or learn the + * project's source code.
+ * + *Integration is essentially as easy as calling {@link #initiateScan(Activity)} and waiting + * for the result in your app.
+ * + *It does require that the Barcode Scanner application is installed. The + * {@link #initiateScan(Activity)} method will prompt the user to download the application, if needed.
+ * + *There are a few steps to using this integration. First, your {@link Activity} must implement + * the method {@link Activity#onActivityResult(int, int, Intent)} and include a line of code like this:
+ * + *{@code + * public void onActivityResult(int requestCode, int resultCode, Intent intent) { + * IntentResult scanResult = IntentIntegrator.parseActivityResult(requestCode, resultCode, intent); + * if (scanResult != null) { + * // handle scan result + * } + * // else continue with any other code you need in the method + * ... + * } + * }
+ * + *This is where you will handle a scan result. + * Second, just call this in response to a user action somewhere to begin the scan process:
+ * + *{@code integrator.initiateScan();}
+ * + *You can use {@link #initiateScan(Activity, String, String, String, String)} or + * {@link #initiateScan(Activity, int, int, int, int)} to customize the download prompt with + * different text labels.
+ * + *Some code, particularly download integration, was contributed from the Anobiit application.
+ * + * @author Sean Owen + * @author Fred Lin + */ +public final class IntentIntegrator { + + public static final int REQUEST_CODE = 0x0ba7c0de; // get it? + + private IntentIntegrator() { + } + + /** + * See {@link #initiateScan(Activity, String, String, String, String)} -- same, but uses default English labels. + */ + public static void initiateScan(Activity activity) { + initiateScan(activity, + "Install Barcode Scanner?", + "This application requires Barcode Scanner. Would you like to install it?", + "Yes", + "No"); + } + + /** + * See {@link #initiateScan(Activity, String, String, String, String)} -- same, but takes string IDs which refer + * to the {@link Activity}'s resource bundle entries. + */ + public static void initiateScan(Activity activity, + int stringTitle, + int stringMessage, + int stringButtonYes, + int stringButtonNo) { + initiateScan(activity, + activity.getString(stringTitle), + activity.getString(stringMessage), + activity.getString(stringButtonYes), + activity.getString(stringButtonNo)); + } + + /** + * Invokes scanning. + * + * @param stringTitle title of dialog prompting user to download Barcode Scanner + * @param stringMessage text of dialog prompting user to download Barcode Scanner + * @param stringButtonYes text of button user clicks when agreeing to download Barcode Scanner (e.g. "Yes") + * @param stringButtonNo text of button user clicks when declining to download Barcode Scanner (e.g. "No") + * @return the contents of the barcode that was scanned, or null if none was found + * @throws InterruptedException if timeout expires before a scan completes + */ + public static void initiateScan(Activity activity, + String stringTitle, + String stringMessage, + String stringButtonYes, + String stringButtonNo) { + Intent intentScan = new Intent("com.google.zxing.client.android.SCAN"); + intentScan.addCategory(Intent.CATEGORY_DEFAULT); + try { + activity.startActivityForResult(intentScan, REQUEST_CODE); + } catch (ActivityNotFoundException e) { + showDownloadDialog(activity, stringTitle, stringMessage, stringButtonYes, stringButtonNo); + } + } + + private static void showDownloadDialog(final Activity activity, + String stringTitle, + String stringMessage, + String stringButtonYes, + String stringButtonNo) { + AlertDialog.Builder downloadDialog = new AlertDialog.Builder(activity); + downloadDialog.setTitle(stringTitle); + downloadDialog.setMessage(stringMessage); + downloadDialog.setPositiveButton(stringButtonYes, new DialogInterface.OnClickListener() { + public void onClick(DialogInterface dialogInterface, int i) { + Uri uri = Uri.parse("market://search?q=pname:com.google.zxing.client.android"); + Intent intent = new Intent(Intent.ACTION_VIEW, uri); + activity.startActivity(intent); + } + }); + downloadDialog.setNegativeButton(stringButtonNo, new DialogInterface.OnClickListener() { + public void onClick(DialogInterface dialogInterface, int i) {} + }); + downloadDialog.show(); + } + + + /** + *Call this from your {@link Activity}'s {@link Activity#onActivityResult(int, int, Intent)} method.
+ * + * @return null if the event handled here was not related to {@link IntentIntegrator}, 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"); + return new IntentResult(contents, formatName); + } else { + return new IntentResult(null, null); + } + } + return null; + } + +}