Overview
DataWedge APIs operate primarily through Android intents - specific commands that can be used by other applications to control data capture without the need to directly access the underlying hardware APIs. Intents are implemented as extras of an action intent, permitting multiple API calls to be sent as extras using a single intent action. This guide describes the functionality of the intents supported by DataWedge and their effects on data capture and DataWedge Profiles and settings.
Note: When querying the DataWedge status (Get DataWedge Status) or sending any intent API to DataWedge soon after a device reboot, DataWedge cannot receive the intent if DataWedge did not start or did not complete the initialization process. Zebra recommends to implement a retry mechanism if a response from DataWedge is not received from the intent API sent to DataWedge.
Additional resources:
- Using Intents - A brief primer on intents and how to configure DataWedge to use them
- DataWedge APIs - Benefits & Usage Scenarios - by Zebra engineer Darryn Campbell
- Sample DataWedge app - Demonstrates how to receive scanned data through an intent
Requirements
The use of DataWedge APIs requires experience with Java programming and familiarity with Android Intents. It also requires knowledge of DataWedge usage, features and terminology. For more information about DataWedge, see the DataWedge Getting Started Guide and the Architecture Overview. It also might be helpful to read the DataWedge section of the Integrator Guide included with Zebra devices.
Sending Intents
Multiple DataWedge API calls can be passed as extras on a single intent action. The syntax is as follows:
// Send multiple intents as extras
Intent i = new Intent();
i.setAction("com.symbol.datawedge.api.ACTION");
String[] profiles = {"MainInventory"};
i.putExtra("com.symbol.datawedge.api.DELETE_PROFILE", profiles);
i.putExtra("com.symbol.datawedge.api.GET_VERSION_INFO", "");Receiving Results
For intents that query DataWedge for information (such as in "GET_ACTIVE_PROFILE"), the app must register to receive the result with a filter that identifies the action and category of the result intent. The code below shows how to register the broadcast receiver to receive the results:
// Register broadcast receiver and filter results
void registerReceivers() {
IntentFilter filter = new IntentFilter();
filter.addAction("com.symbol.datawedge.api.RESULT_ACTION");
filter.addCategory("android.intent.category.DEFAULT");
registerReceiver(mybroadcastReceiver, filter);
}
//Receiving the result
private BroadcastReceiver myBroadcastReceiver = new BroadcastReceiver(){
@Override
public void onReceive(Context context, Intent intent){
Bundle extras = getIntent().getExtras();
if (intent.hasExtra("com.symbol.datawedge.api.RESULT_GET_ACTIVE_PROFILE")){
String activeProfile = extras.getString("com.symbol.datawedge.api.RESULT_GET_ACTIVE_PROFILE");Important: DataWedge API commands are not queued, and might be ignored if sent while DataWedge is busy processing an earlier intent. When an API command is sent, DataWedge executes the command only if it is not busy doing something else. Exceptions:
STOP_SCANNING- immediately interrupts a scan operationDISABLE_PLUGIN- immediately disables the current scanner input plug-in
To help ensure proper execution, Zebra recommends inserting delay code prior to critical commands. See the SoftScanTrigger API for an example.
Nested Bundles
Nested bundles allows a "bundle" of values to be included as one value in another bundle. Bundles also can be multiple layers deep. For example, the image below illustrates a PARAM_LIST bundle nested within the PLUGIN_CONFIG[0] bundle nested within the API call SET_CONFIG. Nesting is required to configure with intents the many parameters contained in a Profile.
The image further illustrates that the SET_CONFIG API call can implement a second nested bundle, PLUGIN_CONFIG[n], which can contain its own PARAM_LIST.
Example
The Java code below implements a nested bundle.
//Using the SET_CONFIG API and a nested bundle.
Bundle bMain = new Bundle();
bMain.putString("PROFILE_NAME","Profile2");
bMain.putString("PROFILE_ENABLED", "true");
bMain.putString("CONFIG_MODE","CREATE_IF_NOT_EXIST");
bMain.putString("RESET_CONFIG", "true");
Bundle bundleApp1 = new Bundle();
bundleApp1.putString("PACKAGE_NAME","com.symbol.emdk.simulscansample1");
bundleApp1.putStringArray("ACTIVITY_LIST", new String[]{
"com.symbol.emdk.simulscansample1.DeviceControl",
"com.symbol.emdk.simulscansample1.MainActivity",
"com.symbol.emdk.simulscansample1.ResultsActivity.*",
"com.symbol.emdk.simulscansample1.ResultsActivity2",
"com.symbol.emdk.simulscansample1.SettingsFragment1"});
Bundle bundleApp2 = new Bundle();
bundleApp2.putString("PACKAGE_NAME","com.example.intents.datawedgeintent");
bundleApp2.putStringArray("ACTIVITY_LIST", new String[]{
"com.example.intents.datawedgeintent.DeviceControl",
"com.example.intents.datawedgeintent.MainActivity",
"com.example.intents.datawedgeintent.ResultsActivity",
"com.example.intents.datawedgeintent.SettingsFragment1"});
Bundle bundleApp3 = new Bundle();
bundleApp3.putString("PACKAGE_NAME","*");
bundleApp3.putStringArray("ACTIVITY_LIST", new String[]{"*"});
Bundle bundleApp4 = new Bundle();
bundleApp4.putString("PACKAGE_NAME","com.symbol.myzebraapp");
bundleApp4.putStringArray("ACTIVITY_LIST", new String[]{"*"});
bMain.putParcelableArray("APP_LIST", new Bundle[]{
bundleApp1
,bundleApp2
,bundleApp3
,bundleApp4
});
Intent i = new Intent();
i.setAction("com.symbol.datawedge.api.ACTION");
i.putExtra("com.symbol.datawedge.api.SET_CONFIG", bMain);
this.sendBroadcast(i);Related Guides:
SEE ALSO:
Zebra Support Central | Integrator Guides, Product Manuals, Software Downloads and Support
LaunchPad | Zebra Developer Community
Intent | Android Developers
Intents and Intent Filters | Android Developers
Android Intents | Tutorial