Knockoutjs And Pubsub To Update Observable Array Between Views

I have two modalviews - MyModalViewA (parent) and MyModalViewB (child). MyModalViewA spawns MyModalViewB, as custom binding, as well has observable array which I need to update. An

Solution 1:

Make sure that the postboxinstance is one and the same instance being shared between both viewmodels and that the notifySubscribersand subcribe methods follow the signatures below.

notifySubscribers(eventData, eventName); 

subscribe(function(eventData) { ... }, null, eventName);

Below you find a simplified version of what you are trying to achieve.
Here only 1 search result is being passed, but it might also be more via eg. an array.

var postbox = ko.observable();

function MyModalViewA()
{
    var _self = this;
    _self.rows = ko.observableArray([
        { label: "foo" },
        { label: "bar" }    
        ]);
    
    postbox.subscribe(function(newValue) {         
          _self.rows.push(newValue);
      }, null, "PFX.NewRowAvailable"
      );
};

function MyModalViewB()
{
    var _self = this;
    
    _self.search = function() {
    
        var newRow = { "label" : "baz" };
        postbox.notifySubscribers(newRow, "PFX.NewRowAvailable");      
    };
};

var vma = new MyModalViewA();
ko.applyBindings(vma, $("#vma").get(0));

var vmb = new MyModalViewB();
ko.applyBindings(vmb, $("#vmb").get(0));

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.4.2/knockout-min.js"></script>

<div id="vma">
    <h3>ViewModel A</h3>
    <ol data-bind="foreach: rows">
        <li data-bind="text: label"></li>
    </ol>
</div>

<hr />

<div id="vmb">    
    <h3>ViewModel B</h3>
    <button data-bind="click: search">search</button>
</div>