[RN] Make all delegate / listener methods run in the main / UI thread

android/app/src/main/java/org/jitsi/meet/MainActivity.java

 import org.jitsi.meet.sdk.invite.InviteControllerListener;
 
 import com.calendarevents.CalendarEventsPackage;
+import com.facebook.react.bridge.UiThreadUtil;
 
 import java.util.ArrayList;
 import java.util.HashMap;
         if (BuildConfig.DEBUG && view != null) {
             view.setListener(new JitsiMeetViewListener() {
                 private void on(String name, Map<String, Object> data) {
+                    UiThreadUtil.assertOnUiThread();
+
                     // Log with the tag "ReactNative" in order to have the log
                     // visible in react-native log-android as well.
                     Log.d(
             inviteController.setListener(new InviteControllerListener() {
                 public void beginAddPeople(
                         AddPeopleController addPeopleController) {
+                    UiThreadUtil.assertOnUiThread();
+
                     onInviteControllerBeginAddPeople(
                         inviteController,
                         addPeopleController);
     private void onAddPeopleControllerInviteSettled(
             AddPeopleController addPeopleController,
             List<Map<String, Object>> failedInvitees) {
+        UiThreadUtil.assertOnUiThread();
+
         // XXX Explicitly invoke endAddPeople on addPeopleController; otherwise,
         // it is going to be memory-leaked in the associated InviteController
         // and no subsequent InviteButton clicks/taps will be delivered.
             AddPeopleController addPeopleController,
             List<Map<String, Object>> results,
             String query) {
+        UiThreadUtil.assertOnUiThread();
+
         int size = results.size();
 
         if (size > 0) {
     private void onInviteControllerBeginAddPeople(
             InviteController inviteController,
             AddPeopleController addPeopleController) {
+        UiThreadUtil.assertOnUiThread();
+
         // Log with the tag "ReactNative" in order to have the log visible in
         // react-native log-android as well.
         Log.d(

android/sdk/src/main/java/org/jitsi/meet/sdk/ExternalAPIModule.java

 import com.facebook.react.bridge.ReactMethod;
 import com.facebook.react.bridge.ReadableMap;
 import com.facebook.react.bridge.ReadableMapKeySetIterator;
-
-import org.jitsi.meet.sdk.JitsiMeetView;
-import org.jitsi.meet.sdk.JitsiMeetViewListener;
+import com.facebook.react.bridge.UiThreadUtil;
 
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
      * @param scope
      */
     @ReactMethod
-    public void sendEvent(String name, ReadableMap data, String scope) {
-        // The JavaScript App needs to provide uniquely identifying information
-        // to the native ExternalAPI module so that the latter may match the
-        // former to the native JitsiMeetView which hosts it.
-        JitsiMeetView view = JitsiMeetView.findViewByExternalAPIScope(scope);
-
-        if (view == null) {
-            return;
-        }
-
-        maybeSetViewURL(name, data, view);
-
-        JitsiMeetViewListener listener = view.getListener();
-
-        if (listener == null) {
-            return;
-        }
-
-        Method method = JITSI_MEET_VIEW_LISTENER_METHODS.get(name);
-
-        if (method != null) {
-            try {
-                method.invoke(listener, toHashMap(data));
-            } catch (IllegalAccessException e) {
-                // FIXME There was a multicatch for IllegalAccessException and
-                // InvocationTargetException, but Android Studio complained
-                // with:
-                // "Multi-catch with these reflection exceptions requires
-                // API level 19 (current min is 16) because they get compiled to
-                // the common but new super type ReflectiveOperationException.
-                // As a workaround either create individual catch statements, or
-                // catch Exception."
-                throw new RuntimeException(e);
-            } catch (InvocationTargetException e) {
-                throw new RuntimeException(e);
+    public void sendEvent(final String name,
+                          final ReadableMap data,
+                          final String scope) {
+        UiThreadUtil.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                // The JavaScript App needs to provide uniquely identifying
+                // information to the native ExternalAPI module so that the
+                // latter may match the former to the native JitsiMeetView which
+                // hosts it.
+                JitsiMeetView view
+                    = JitsiMeetView.findViewByExternalAPIScope(scope);
+
+                if (view == null) {
+                    return;
+                }
+
+                maybeSetViewURL(name, data, view);
+
+                JitsiMeetViewListener listener = view.getListener();
+
+                if (listener == null) {
+                    return;
+                }
+
+                Method method = JITSI_MEET_VIEW_LISTENER_METHODS.get(name);
+
+                if (method != null) {
+                    try {
+                        method.invoke(listener, toHashMap(data));
+                    } catch (IllegalAccessException e) {
+                        // FIXME There was a multicatch for
+                        // IllegalAccessException and InvocationTargetException,
+                        // but Android Studio complained with: "Multi-catch with
+                        // these reflection exceptions requires API level 19
+                        // (current min is 16) because they get compiled to the
+                        // common but new super type
+                        // ReflectiveOperationException. As a workaround either
+                        // create individual catch statements, or
+                        // catch Exception."
+                        throw new RuntimeException(e);
+                    } catch (InvocationTargetException e) {
+                        throw new RuntimeException(e);
+                    }
+                }
             }
-        }
+        });
     }
 
     /**

android/sdk/src/main/java/org/jitsi/meet/sdk/invite/InviteModule.java

 import com.facebook.react.bridge.ReactContextBaseJavaModule;
 import com.facebook.react.bridge.ReactMethod;
 import com.facebook.react.bridge.ReadableArray;
+import com.facebook.react.bridge.UiThreadUtil;
 
 import org.jitsi.meet.sdk.JitsiMeetView;
 
      * {@code JitsiMeetView} whose {@code InviteButton} was clicked/tapped.
      */
     @ReactMethod
-    public void beginAddPeople(String externalAPIScope) {
-        InviteController inviteController
-            = findInviteControllerByExternalAPIScope(externalAPIScope);
+    public void beginAddPeople(final String externalAPIScope) {
+        UiThreadUtil.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                InviteController inviteController
+                    = findInviteControllerByExternalAPIScope(externalAPIScope);
 
-        if (inviteController != null) {
-            inviteController.beginAddPeople(getReactApplicationContext());
-        }
+                if (inviteController != null) {
+                    inviteController.beginAddPeople(getReactApplicationContext());
+                }
+            }
+        });
     }
 
     private InviteController findInviteControllerByExternalAPIScope(
      */
     @ReactMethod
     public void inviteSettled(
-            String externalAPIScope,
-            String addPeopleControllerScope,
-            ReadableArray failedInvitees) {
-        InviteController inviteController
-            = findInviteControllerByExternalAPIScope(externalAPIScope);
+            final String externalAPIScope,
+            final String addPeopleControllerScope,
+            final ReadableArray failedInvitees) {
+        UiThreadUtil.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                InviteController inviteController
+                    = findInviteControllerByExternalAPIScope(externalAPIScope);
 
-        if (inviteController == null) {
-            Log.w(
-                "InviteModule",
-                "Invite settled, but failed to find active controller to notify");
-        } else {
-            inviteController.inviteSettled(
-                addPeopleControllerScope,
-                failedInvitees);
-        }
+                if (inviteController == null) {
+                    Log.w(
+                        "InviteModule",
+                        "Invite settled, but failed to find active controller to notify");
+                } else {
+                    inviteController.inviteSettled(
+                        addPeopleControllerScope,
+                        failedInvitees);
+                }
+            }
+        });
     }
 
     /**
      */
     @ReactMethod
     public void receivedResults(
-            String externalAPIScope,
-            String addPeopleControllerScope,
-            String query,
-            ReadableArray results) {
-        InviteController inviteController
-            = findInviteControllerByExternalAPIScope(externalAPIScope);
+            final String externalAPIScope,
+            final String addPeopleControllerScope,
+            final String query,
+            final ReadableArray results) {
+        UiThreadUtil.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                InviteController inviteController
+                    = findInviteControllerByExternalAPIScope(externalAPIScope);
 
-        if (inviteController == null) {
-            Log.w(
-                "InviteModule",
-                "Received results, but failed to find active controller to send results back");
-        } else {
-            inviteController.receivedResultsForQuery(
-                addPeopleControllerScope,
-                query,
-                results);
-        }
+                if (inviteController == null) {
+                    Log.w(
+                        "InviteModule",
+                        "Received results, but failed to find active controller to send results back");
+                } else {
+                    inviteController.receivedResultsForQuery(
+                        addPeopleControllerScope,
+                        query,
+                        results);
+                }
+            }
+        });
     }
 }

ios/app/src/ViewController.m

  * limitations under the License.
  */
 
+#import <assert.h>
+
 #import "ViewController.h"
 
 /**
     NSLog(
         @"[%s:%d] JitsiMeetViewDelegate %@ %@",
         __FILE__, __LINE__, name, data);
+
+    assert([NSThread isMainThread]
+        && "Delegate method called in a non-main thread");
 }
 
 - (void)conferenceFailed:(NSDictionary *)data {
         @"[%s:%d] JMInviteControllerDelegate %s",
         __FILE__, __LINE__, __FUNCTION__);
 
+    assert([NSThread isMainThread]
+        && "Delegate method called in a non-main thread");
+
     NSString *query = ADD_PEOPLE_CONTROLLER_QUERY;
     JitsiMeetView *view = (JitsiMeetView *) self.view;
     JMInviteController *inviteController = view.inviteController;
 - (void)addPeopleController:(JMAddPeopleController * _Nonnull)controller
           didReceiveResults:(NSArray<NSDictionary *> * _Nonnull)results
                    forQuery:(NSString * _Nonnull)query {
+    assert([NSThread isMainThread]
+        && "Delegate method called in a non-main thread");
+
     NSUInteger count = results.count;
 
     if (count) {
 
 - (void) inviteSettled:(NSArray<NSDictionary *> * _Nonnull)failedInvitees
   fromSearchController:(JMAddPeopleController * _Nonnull)addPeopleController {
+    assert([NSThread isMainThread]
+        && "Delegate method called in a non-main thread");
+
     // XXX Explicitly invoke endAddPeople on addPeopleController; otherwise, it
     // is going to be memory-leaked in the associated JMInviteController and no
     // subsequent InviteButton clicks/taps will be delivered. Technically,

ios/sdk/src/ExternalAPI.m

 
 RCT_EXPORT_MODULE();
 
+/**
+ * Make sure all methods in this module are called in the main (i.e. UI) thread.
+ */
+- (dispatch_queue_t)methodQueue {
+    return dispatch_get_main_queue();
+}
+
 /**
  * Dispatches an event that occurred on JavaScript to the view's delegate.
  *

ios/sdk/src/invite/Invite.m

     ];
 }
 
+/**
+ * Make sure all methods in this module are called in the main (i.e. UI) thread.
+ */
+- (dispatch_queue_t)methodQueue {
+    return dispatch_get_main_queue();
+}
+
 /**
  * Initiates the process to add people. This involves calling a delegate method
  * in the JMInviteControllerDelegate so the native host application can start