[android-extensions] Set RECEIVER_NOT_EXPORTED in ServerPingWithAlarmManager

Set RECEIVER_NOT_EXPORTED when registering the receiver in
ServerPingWithAlarmManager, as otherwise this will throw an exception
if the application targets Android API level 34 or higher.

This requires raising the minimum Android API level to 26 for
registerReceiver() with flags.

.github/workflows/ci.yml

@@ -56,7 +56,7 @@ jobs:
         uses: android-actions/setup-android@v3
       - name: Install Android SDK
         run: |
-          sdkmanager "platforms;android-23"
+          sdkmanager "platforms;android-26"
 
       # Testing
       - name: Gradle Check

build-logic/src/main/groovy/org.igniterealtime.smack.android-conventions.gradle

@@ -3,7 +3,7 @@ plugins {
 	id 'org.igniterealtime.smack.global-conventions'
 }
 dependencies {
-	signature "net.sf.androidscents.signature:android-api-level-${smackMinAndroidSdk}:6.0_r3@signature"
+	signature "net.sf.androidscents.signature:android-api-level-${smackMinAndroidSdk}:8.0.0_r2@signature"
 }
 animalsniffer {
 	sourceSets = [sourceSets.main]

build-logic/src/main/groovy/org.igniterealtime.smack.global-conventions.gradle

@@ -1,7 +1,7 @@
 ext {
 	javaVersion = JavaVersion.VERSION_11
 	javaMajor = javaVersion.getMajorVersion()
-	smackMinAndroidSdk = 23
+	smackMinAndroidSdk = 26
 
 	androidBootClasspath = { getAndroidRuntimeJar() }
 }

smack-android-extensions/src/main/java/org/jivesoftware/smackx/ping/android/ServerPingWithAlarmManager.java

@@ -173,7 +173,13 @@ public final class ServerPingWithAlarmManager extends Manager {
      */
     public static void onCreate(Context context) {
         sContext = context;
-        context.registerReceiver(ALARM_BROADCAST_RECEIVER, new IntentFilter(PING_ALARM_ACTION));
+
+        int receiverFlags = 0;
+        if (Build.VERSION.SDK_INT >= 34) {
+            receiverFlags |= 4; // RECEIVER_NOT_EXPORTED
+        }
+        context.registerReceiver(ALARM_BROADCAST_RECEIVER, new IntentFilter(PING_ALARM_ACTION), receiverFlags);
+
         sAlarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
         int pendingIntentFlags = 0;
         if (Build.VERSION.SDK_INT >= 23) {