Library migration to AndroidX - mqtt

Question

I'm using Paho MQTT library in my AndroidX application. I'm getting exception NoClassDefFoundError for Landroid/support/v4/content/LocalBroadcastManager. I found that library uses depricated import:
import android.support.v4.content.LocalBroadcastManager;
Function that rises exception:
private void registerReceiver(BroadcastReceiver receiver) {
IntentFilter filter = new IntentFilter();
filter.addAction(MqttServiceConstants.CALLBACK_TO_ACTIVITY);
LocalBroadcastManager.getInstance(myContext).registerReceiver(receiver, filter);
receiverRegistered = true;
}
How to solve this problem? Should I download source and recompile library? Why it is not already done in latest release?
Whole exception:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.eurbon.pahomqttclientexample, PID: 17368
java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v4/content/LocalBroadcastManager;
at org.eclipse.paho.android.service.MqttAndroidClient.registerReceiver(MqttAndroidClient.java:450)
at org.eclipse.paho.android.service.MqttAndroidClient.connect(MqttAndroidClient.java:428)
at org.eclipse.paho.android.service.MqttAndroidClient.connect(MqttAndroidClient.java:334)
at paho.android.mqtt_example.MainActivity.MqttConnect(MainActivity.java:121)
at paho.android.mqtt_example.MainActivity.onCreate(MainActivity.java:63)
at android.app.Activity.performCreate(Activity.java:6679)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.v4.content.LocalBroadcastManager" on path: DexPathList[[zip file "/data/app/com.eurbon.pahomqttclientexample-1/base.apk"],nativeLibraryDirectories=[/data/app/com.eurbon.pahomqttclientexample-1/lib/x86, /system/lib, /vendor/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:380)
at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
at org.eclipse.paho.android.service.MqttAndroidClient.registerReceiver(MqttAndroidClient.java:450) 
at org.eclipse.paho.android.service.MqttAndroidClient.connect(MqttAndroidClient.java:428) 
at org.eclipse.paho.android.service.MqttAndroidClient.connect(MqttAndroidClient.java:334) 
at paho.android.mqtt_example.MainActivity.MqttConnect(MainActivity.java:121) 
at paho.android.mqtt_example.MainActivity.onCreate(MainActivity.java:63) 
at android.app.Activity.performCreate(Activity.java:6679) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726) 
at android.app.ActivityThread.-wrap12(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:154) 
at android.app.ActivityThread.main(ActivityThread.java:6119) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 

Answer 1

After migrating a project to AndroidX, I don't think you can use android.support.v* anymore. What if you try and use the content support library from androidx.core and not android.support.v4; I think that will resolve the issue for you.
import androidx.core.content.LocalBroadcastManager;
If you're using Android Studio the intellisense should be pretty helpful in resolving other dependency issues and/or other errors/warnings due to the AndroidX migration and the suggested change to support library providers.