public static interface TextBuffer.NotifyCursorPosition

Signal emitted when the cursor-position property changes. This is a good way to find out that the cursor has moved.

 buffer.connect(new TextBuffer.NotifyCursorPosition()) {
     public void onNotifyCursorPosition(TextBuffer source) {
          final int offset;
          
          offset = buffer.getCursorPosition();
     }
 });
 

If you've already got the insert TextMark, then you could instead do:

 buffer.connect(new TextBuffer.NotifyCursorPosition()) {
     public void onNotifyCursorPosition(TextBuffer source) {
          final TextIter pointer;
          final int offset;
          
          pointer = buffer.getIter(insertBound);
          offset = buffer.getOffset();
     }
 });
 

which amounts to the same thing.

Using the TextBuffer.NotifyCursorPosition signal is much more efficient than hooking up to TextBuffer.MarkSet signals.