Tutorial - How to Receive Scanned Barcode Data in Java

A walk-through on how to receive scanned barcode data through an Android intent.

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Product

DataWedge - 11.0

Devices

All supported Zebra Android devices

Overview

This tutorial demonstrates how to use DataWedge to receive scanned barcode data through an Android intent with the sample application BasicIntent1. The high level steps are:

  1. Configure DataWedge. Set the input (barcode scanner) and output (intent).
  2. Create a profile and associate the app with the profile.
  3. Run the app and scan a barcode.

This sample application is only intended for educational purposes, demonstrating the use of DataWedge intent API(s).

This is the minimal code approach using a generic Android intent rather than DataWedge APIs. To develop an app with finer control of DataWedge settings and data capture, refer to the DataWedge API guide and best practices in the Get Started guide.

Steps

  1. Launch DataWedge. From the apps menu tap DataWedge.

  2. Create a new profile. Alternatively, Profile0 (the default profile used by all apps not explicitly assigned a profile) can be used.

  3. Associate sample app BasicIntent1 to the profile. Open the profile created from step 2 and perform the following:
         a. Tap Associated Apps.
         b. In the top right menu, select New app/activity.
         c. Select com.zebra.basicintent1.
         d. Select *.

  4. Confirm the following settings in the profile:

    • The profile is enabled
    • Barcode input is enabled
    • Intent output is enabled

  5. Configure the intent output as follows:

    • Intent action: com.dwbasicintent1.ACTION
      (This is an implicit intent that is sent by DataWedge. The application must register a broadcast receiver with the given action in order to receive the intent. For this tutorial in conjunction with BasicIntent1 sample, use: com.dwbasicintent1.ACTION)
    • Intent category: (leave blank)
    • Intent delivery: Broadcast intent

    Refer to the DataWedge Intent Output guide for more information about these settings.

  6. Download, build and launch the sample app BasicIntent1.

  7. Scan a barcode.

  8. The scanned data is displayed.

Sample code walk-through

Refer to BasicIntent1 sample app source code.

There are several important points to ensure that the app receives the intent data sent from DataWedge:

  1. Pre-define some of the strings in the application project for ease of use when extracting the scanned data. The intent action is defined as `activity_intent_filter_action` in the sample app. When received, the intent’s action contains extras with the scanned data for source, type, and data as described in the DataWedge Intent Output guide. Content from Strings.xml in the sample app: 
        <resources>
        <string name="app_name">DW BasicIntent1</string>
        <string name="activity_intent_filter_action">com.dwbasicintent1.ACTION</string>
        <string name="datawedge_intent_key_source">com.symbol.datawedge.source</string>
        <string name="datawedge_intent_key_label_type">com.symbol.datawedge.label_type</string>
        <string name="datawedge_intent_key_data">com.symbol.datawedge.data_string</string>
    </resources>

  2. Register a broadcast receiver. Since DataWedge is configured to send a broadcast intent, the application must register a broadcast receiver. This is done in the onCreate() method in the sample app:

        protected void onCreate(Bundle savedInstanceState) {
        IntentFilter filter = new IntentFilter();
        filter.addCategory(Intent.CATEGORY_DEFAULT);
        filter.addAction(getResources().getString(R.string.activity_intent_filter_action));
        registerReceiver(myBroadcastReceiver, filter);
    }

    Note that the action being filtered matches the action configured in the DataWedge profile. In a production application, for efficiency the register/unregister would likely be done in the onResume()/onPause() methods.

  3. Define the broadcast receiver. This is done in MainActivity.java in the sample app:

        private BroadcastReceiver myBroadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            Bundle b = intent.getExtras();


            if (action.equals(getResources().getString(R.string.activity_intent_filter_action))) {
            //  Received a barcode scan
            try {
                displayScanResult(intent, "via Broadcast");
            } catch (Exception e) {
                //  Catch if the UI does not exist when we receive the broadcast
            }
        }
    }
};

  4. Extract the scanned data and display it on the screen. This is done in method displayScanResult() in the sample app:

    private void displayScanResult(Intent initiatingIntent, String howDataReceived)
{
        String decodedSource = initiatingIntent.getStringExtra(getResources().getString(R.string.datawedge_intent_key_source));
        String decodedData = initiatingIntent.getStringExtra(getResources().getString(R.string.datawedge_intent_key_data));
        String decodedLabelType = initiatingIntent.getStringExtra(getResources().getString(R.string.datawedge_intent_key_label_type));


        final TextView lblScanSource = (TextView) findViewById(R.id.lblScanSource);
    final TextView lblScanData = (TextView) findViewById(R.id.lblScanData);
    final TextView lblScanLabelType = (TextView) findViewById(R.id.lblScanDecoder);

    lblScanSource.setText(decodedSource + " " + howDataReceived);
    lblScanData.setText(decodedData);
    lblScanLabelType.setText(decodedLabelType);

    

}

Note that the extra keys were defined earlier in the strings.xml file. This code assumes a UI exists in which to place the data, as performed in the sample app.

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