CK

// Check whether the room exists to handled the cases where the user is invited or he has joined.
                    // CAUTION: the room may exist whereas the user membership is neither invited nor joined.
                    final Room room = mSession.getDataHandler().getRoom(publicRoom.roomId, false);
                    if (null != room && room.isInvited()) {
                        Log.d(LOG_TAG, "manageRoom : the user is invited -> display the preview " + VectorApp.getCurrentActivity());
                        CommonActivityUtils.previewRoom(getActivity(), roomPreviewData);
                    } else if (null != room && room.isJoined()) {
                        Log.d(LOG_TAG, "manageRoom : the user joined the room -> open the room");
                        final Map<String, Object> params = new HashMap<>();
                        params.put(VectorRoomActivity.EXTRA_MATRIX_ID, mSession.getMyUserId());
                        params.put(VectorRoomActivity.EXTRA_ROOM_ID, publicRoom.roomId);

                        if (!TextUtils.isEmpty(publicRoom.name)) {
                            params.put(VectorRoomActivity.EXTRA_DEFAULT_NAME, publicRoom.name);
                        }

                        if (!TextUtils.isEmpty(publicRoom.topic)) {
                            params.put(VectorRoomActivity.EXTRA_DEFAULT_TOPIC, publicRoom.topic);
                        }

                        CommonActivityUtils.goToRoomPage(getActivity(), mSession, params);
                    } else {
                        // Display a preview by default.
                        Log.d(LOG_TAG, "manageRoom : display the preview");
                        mInitializationSpinnerView.setVisibility(View.VISIBLE);

                        roomPreviewData.fetchPreviewData(new ApiCallback<Void>() {
                            private void onDone() {
                                if (!isAdded()) {
                                    return;
                                }

                                mInitializationSpinnerView.setVisibility(View.GONE);
                                CommonActivityUtils.previewRoom(getActivity(), roomPreviewData);
                            }

                            @Override
                            public void onSuccess(Void info) {
                                onDone();
                            }

                            private void onError() {
                                if (!isAdded()) {
                                    return;
                                }

                                roomPreviewData.setPublicRoom(publicRoom);
                                roomPreviewData.setRoomName(publicRoom.name);
                                onDone();
                            }

                            @Override
                            public void onNetworkError(Exception e) {
                                onError();
                            }

                            @Override
                            public void onMatrixError(MatrixError e) {
                                onError();
                            }

                            @Override
                            public void onUnexpectedError(Exception e) {
                                onError();
                            }
                        });
                    }