如何通过createElement（）在聚合物中添加扩展元素

Question

 var elm = document.createElement("tr");                
 this.$.myLovelyContainer.appendChild(elm);

I need to add a <tr is="custom-tag"...> node in myLovelyContainer.

Thx for help guys :)

--- more info I just saw

The problem is when I add this via document.createelement , it creates but does not create the content of it. This is an extended tr element that has td tags in it.

It just adds the tag in page but it is always invisible. And the custom-element fucntions does not work.

Answer 1

Try this (for a table with id = myLovelyContainer):

var elm = document.createElement("tr");
var a = document.createAttribute( "is" );
a.value = "custom-tag";
elm.setAttributeNode(a);
var elm2 = document.createElement("td");
var content = document.createTextNode( "Hello world!" ); 
elm2.appendChild( content );
elm.appendChild( elm2 );
var myLovelyContainer = document.getElementById( 'myLovelyContainer' );
myLovelyContainer.appendChild(elm);

Fiddle: https://jsfiddle.net/tbdycybm/

Answer 2

Here is the solution

var elm = document.createElement("tr","custom-tag");

I needed mor research but now I am happy :) By this creation way it just acts normal, creates its content and initializez all properties and methods.

I wish polymer has much more detailed tutorials.