Added a wait for EMDK mechanism.

This can become handy when your app respond to the BOOT_COMPLETED event.
Changed the architecture of the sample.

DeviceIdentifiersWrapper/build.gradle

@@ -10,7 +10,7 @@ android {
     compileSdkVersion 32
 
     defaultConfig {
-        minSdkVersion 19
+        minSdkVersion 28
         targetSdkVersion 32
         versionCode 4
         versionName "0.4"
@@ -25,6 +25,10 @@ android {
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
         }
     }
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
 
 }
 

DeviceIdentifiersWrapper/src/main/java/com/zebra/deviceidentifierswrapper/DIHelper.java

@@ -27,6 +27,9 @@ public class DIHelper {
     protected static String sIMEI = null;
     protected static String sSerialNumber = null;
 
+    private static final long MIN_IN_MS = 1000 * 60;
+    public static long MAX_EMDK_TIMEOUT_IN_MS = 10 * MIN_IN_MS; // 10 minutes
+
     public static void resetCachedValues()
     {
         sIMEI = null;

DeviceIdentifiersWrapper/src/main/java/com/zebra/deviceidentifierswrapper/DIProfileManagerCommand.java

@@ -17,6 +17,7 @@
 
 import java.io.StringReader;
 import java.util.ArrayList;
+import java.util.Date;
 
 class DIProfileManagerCommand extends DICommandBase {
     public class ErrorHolder
@@ -55,6 +56,8 @@ public class ErrorHolder
     // Provides full error description string
     public String msErrorString = "";
 
+    private boolean bInitializing = false;
+
     // Status Listener implementation (ensure that we retrieve the profile manager asynchronously
     EMDKManager.StatusListener mStatusListener = new EMDKManager.StatusListener() {
         @Override
@@ -114,6 +117,9 @@ public void execute(String mxProfile, String mxProfileName, IDIResultCallbacks r
 
     private void initializeEMDK()
     {
+        if(bInitializing)
+            return;
+        bInitializing = true;
         if(mEMDKManager == null)
         {
             EMDKResults results = null;
@@ -126,6 +132,7 @@ private void initializeEMDK()
             {
                 logMessage("Error while requesting EMDKManager.\n" + e.getLocalizedMessage(), EMessageType.ERROR);
                 e.printStackTrace();
+                waitForEMDK();
                 return;
             }
 
@@ -134,6 +141,7 @@ private void initializeEMDK()
                 logMessage("EMDKManager request command issued with success", EMessageType.DEBUG);
             }else {
                 logMessage("EMDKManager request command error", EMessageType.ERROR);
+                waitForEMDK();
             }
         }
         else
@@ -142,6 +150,29 @@ private void initializeEMDK()
         }
     }
 
+    private void waitForEMDK()
+    {
+        Thread t = new Thread(new Runnable() {
+            @Override
+            public void run() {
+                long startDate = new Date().getTime();
+                long delta = 0;
+                long maxWait = 1000 * 60 * 10; // We will try for 10 mns... before stopping
+                while(mEMDKManager == null || delta < DIHelper.MAX_EMDK_TIMEOUT_IN_MS ) {
+                    initializeEMDK();
+                    try {
+                        Thread.sleep(5000);
+                    } catch (InterruptedException e) {
+                        e.printStackTrace();
+                    }
+                    delta = new Date().getTime() - startDate;
+                }
+            }
+        });
+        t.setPriority(Thread.MIN_PRIORITY);
+        t.start();
+    }
+
     private void onEMDKManagerRetrieved(EMDKManager emdkManager)
     {
         mEMDKManager = emdkManager;
@@ -186,6 +217,7 @@ private void releaseManagers()
     private void onProfileManagerInitialized(ProfileManager profileManager)
     {
         mProfileManager = profileManager;
+        bInitializing = false;
         logMessage("Profile Manager retrieved.", EMessageType.DEBUG);
         processMXContent();
     }

DeviceIdentifiersWrapper/src/main/java/com/zebra/deviceidentifierswrapper/RetrieveOEMInfoTask.java

@@ -1,5 +1,6 @@
 package com.zebra.deviceidentifierswrapper;
 
+import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
@@ -163,7 +164,7 @@ private static void getURIValue(Cursor cursor, Uri uri, IDIResultCallbacks resul
             else{
                 for (int i = 0; i < cursor.getColumnCount(); i++) {
                     try {
-                        String data = cursor.getString(cursor.getColumnIndex(cursor.getColumnName(i)));
+                        @SuppressLint("Range") String data = cursor.getString(cursor.getColumnIndex(cursor.getColumnName(i)));
                         resultCallbacks.onSuccess(data);
                         cursor.close();
                         return;

README.md

@@ -11,8 +11,16 @@
 ## Sample Repository
 https://github.com/ltrudu/DeviceIdentifiersWrapper-Sample
 
-
-## Update for A11
+## V0.4 : Basic cache mechanism
+```text
+        Added basic cache mechanism.
+		The IMei and the Serial number will be cached once they get retrieved.
+		The cache can be reset with the method: 
+		DIHelper.resetCachedValues()
+		Added a mechanism to wait for the EMDK if it is not available (when responding to the BOOT_COMPLETED event for ex.
+		To be tested... feel free to report any issue regarding this feature.
+```
+## V0.3 : Update for A11
 ```text
         Update your graddle distribution to >= 7.3.3
         update your compileSdkVersion to 30