ko-tinyMCE.js

//tested this myself
//should probably also try
//https://github.com/knockout/knockout/wiki/Bindings---tinyMCE

tinymce.init({
    setup: function (ed) {
        ed.on('keyup', function (e) {
            tinyMceChange(ed);
        });
        ed.on('change', function(e) {
            tinyMceChange(ed);
        });
    }
});

ko.bindingHandlers.tinymce = {
    init: function (element, valueAccessor, allBindingsAccessor, context) {
        var options    = allBindingsAccessor().tinymceOptions || {};
        var modelValue = valueAccessor();
        var value      = ko.utils.unwrapObservable(valueAccessor());
        var el         = $(element)
        

        //handle edits made in the editor. Updates after an undo point is reached.
        options.setup = function (ed) {
            var updateContent = function(){
                if (ko.isWriteableObservable(modelValue)) {
                    modelValue(ed.getContent());
                }
            }
            console.log(ed)
            ed.onChange.add(updateContent);
            ed.onKeyUp.add(updateContent);
            ed.onNodeChange.add(updateContent);
        };

        //handle destroying an editor 
        ko.utils.domNodeDisposal.addDisposeCallback(element, function () {
            setTimeout(function(){$(element).tinymce().remove()}, 0)
        });

        //$(element).tinymce(options);
        setTimeout(function() { $(element).tinymce(options); }, 0);
        el.html(value);

    },
    update: function (element, valueAccessor, allBindingsAccessor, context) {
        var el = $(element)
        var value = ko.utils.unwrapObservable(valueAccessor());
        var id = el.attr('id')
        
        //handle programmatic updates to the observable
        // also makes sure it doesn't update it if it's the same. 
        // otherwise, it will reload the instance, causing the cursor to jump.
        if (id !== undefined ){
            var content = tinyMCE.getInstanceById(id).getContent({format: 'raw'})
            if (content !== value) {
                el.html(value);
            }
        }
    }
};




var viewModel = {
    fieldOne: ko.observable("one"),
    fieldTwo: ko.observable("two"),
    fieldThree: ko.observable("three") 
};
    
ko.applyBindings(viewModel);