to share a feed item (which is a type of feed
element) to a group and add a comment.
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
textSegmentInput.text = 'I hope you enjoy this post I found in another group.';
messageBodyInput.messageSegments.add(textSegmentInput);
feedItemInput.body = messageBodyInput;
feedItemInput.feedElementType = ConnectApi.FeedElementType.FeedItem;
feedItemInput.originalFeedItemId = '0D5RR0000004Grs';
feedItemInput.subjectId = '0F9RR0000004CPw';
ConnectApi.FeedElement feedElement = ConnectApi.ChatterFeeds.postFeedElement(null, feedItemInput, null);