custom.js no longer triggering on app_initialized.NotebookApp

[andyneff]

Using notebook 5.0.0, my custom.js files is no longer triggering app_initialized.NotebookApp.

1. Add the following to custom.js

define(['base/js/events'], function(events) {
    events.on('app_initialized.NotebookApp', function () {
        console.log('app_initialized.NotebookApp');
    });
});

2. Open a notebook and 'app_initialized.NotebookApp' is never logged. However, code outside the 'app_initialized.NotebookApp' callback will be called.

[AndreWin]

Hello!

I have a similar problem. My code has stoped to work in notebook 5.0.0:

define([
    'base/js/namespace',
    'codemirror/keymap/sublime', // Это тоже js файл!
    'base/js/events'
    ], 
    function(IPython, sublime_keymap, events) {
        events.on("app_initialized.NotebookApp", 
            function () {
                console.log("Load settings for codemirror cells")
                var cell = require("notebook/js/cell").Cell;
                cell.options_default.cm_config.lineNumbers = true;
                cell.options_default.cm_config.keyMap = 'sublime';
                cell.options_default.cm_config.lineWrapping = true;
                cell.options_default.cm_config.autoCloseBrackets = true;
            }
        );
    }
);

How can I fix this?

[AndreWin]

Outside of events.on() my code will be run, but too late...

[takluyver]

We should really have a promise for one-time events like this, so you can easily have code that waits for it, without worrying whether it already fired.

[scott-vsi]

Is there any workaround for this issue?

[takluyver]

This is kind-of fixed by #2710 (coming in notebook 5.1). The idea is that code that was previously using the app_initialized event can now use a promise instead:

define([
        'base/js/namespace',
        'base/js/promises'
     ], function(Jupyter, promises) {
         promises.app_initialized.then(function(appname) {
             if (appname === 'NotebookApp') {
                 do_stuff()
             }
         });
     });

Unlike events, if the promise has already been resolved before you do this, then your code is run immediately. With events, it sits waiting for the event to fire again, which this one never does.

I think that's as solved as this is likely to get, so I'm going to close the issue.

[didiercrunch]

It would be nice to update the documentation: https://github.com/jupyter/notebook/blob/4.0.x/notebook/static/custom/custom.js

[jason-s]

Is there a workaround for Jupyter 5.0? Anaconda doesn't seem to have anything newer.

You are using Jupyter notebook.

The version of the notebook server is 5.0.0 and is running on:
Python 2.7.14 |Anaconda, Inc.| (default, Oct 15 2017, 03:34:40) [MSC v.1500 64 bit (AMD64)]

[takluyver]

It definitely should have newer versions that 5.0; we're up to 5.4.1 now, and Anaconda usually packages a new version within a few days of a release.