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Cannot read property 'insertBefore' of null

See original GitHub issue

Looks like this is occurring in the createNewHosts function call.

function createNewHosts(cmps) {
    var components = cmps.map(function (componentNode) {
        var newNode = document.createElement(componentNode.tagName);
        // display none
        var currentDisplay = newNode.style.display;
        newNode.style.display = 'none';
        var parentNode = componentNode.parentNode;
        parentNode.insertBefore(newNode, componentNode); //Problem hits here

         //Potential fix simple but could avoid this in future. 
         if ( !!componentNode.parentNode ) {
              var parentNode = componentNode.parentNode;
              parentNode.insertBefore(newNode, componentNode);
         }

        return { currentDisplay: currentDisplay, newNode: newNode };
    });

Issue Analytics

State:
Created 6 years ago
Comments:5 (1 by maintainers)

Top GitHub Comments

1reaction

Minh-Vancommented, Jun 2, 2018

I got same problem. Any update for this issue ?

0reactions

montella1507commented, Jun 12, 2018

The problem seems to be here in Helpers.js

var parentNode = componentNode.parentNode; <<< componentNode is “app-component” selector, parentNode is “NULL”… however… parent node in DOM is <body>
var currentDisplay = newNode.style.display; newNode.style.display = ‘none’; parentNode.insertBefore(newNode, componentNode);

maybe it is because of angular 6 ?