QTextDocument dynamically removing resources

[lukass]

Hello.

I insert image to QTextEdit:

ui.textEdit->document()->addResource(QTextDocument::ImageResource, url, img);
QTextImageFormat imageFormat;
imageFormat.setName(url);
 
ui.textEdit->textCursor().insertImage(imageFormat);

ui.textEdit->document()->addResource(QTextDocument::ImageResource, url, img);
QTextImageFormat imageFormat;
imageFormat.setName(url);

ui.textEdit->textCursor().insertImage(imageFormat);

To copy to clipboard, switch view to plain text mode 

where url is unique name and img contain image.

How can I dynamically remove this resource after the user delete image(by normal editing document, eg. by 'Backspace' key)?