如何检测插入或删除图像

Question

NSTextAttachment *textAttachment = [[NSTextAttachment alloc] init];
textAttachment.bounds = rect;
textAttachment.image = image;

NSAttributedString *attachmentString = [NSAttributedString attributedStringWithAttachment:textAttachment];

NSMutableAttributedString *attributedText = [[NSMutableAttributedString alloc] initWithAttributedString:self.contentTV.attributedText];
[attributedText replaceCharactersInRange:_lastSelectedRange withAttributedString:attributedString];

self.contentTV.attributedText = attributedText;

这是我的代码，但是当我插入图片时，textView不会调用委托方法：- (BOOL)textView: shouldChangeTextInRange: replacementText:和- (void)textViewDidChange:

任何人都可以帮助我吗？感谢。