Hello Cuong,

If possible I'd recommend that you use on as it has superseded delegate in jQuery 1.7 and later. In regards to the blur event you would instead want to handle the igtexteditorblur or ignumericeditorblur events:

   $('#textEditor').on('igtexteditorblur', function (evt) {
    var editorValue = $(this).igTextEditor('option', 'value');
    console.log('Blur value: ' + editorValue);
   });

For the textChanged event I believe the issue you are encountering is that the event name needs to be all lower case. This looks to be a bug in our API documentation where we demonstrate using the upper case letter. The correct approach would look something like the following:

   $('#textEditor').on('igtexteditortextchanged', function (evt, ui) {
    console.log('Old text: ' + ui.oldText + ', new text: ' + ui.text);
   });

Please let me know if you need any additional information.