Open up color picker from a button click

  $("#myDiagramDiv").append("<div><input  type='color'/></div>"); 

on button click adding this does not solve the problem however the div is also not clickable.
I need option to change color on button click

I assume you have already seen a similar piece of functionality, although one that is much more general than just choosing some color: HTML Interaction

You appear to be using jQuery, so your click event handler could set up your HTML based on the clicked Node data, then call jQuery("#myDialog").dialog({ modal: true });, and finally update the Node data when the dialog is successfully closed.

Actually I already gone thru this example, but just need a button as a color picker type, means click a custom button as a color picker and option to select colors appears like, can your button be extended as a color picker type?
<input type="color"> - HTML: HyperText Markup Language | MDN

Moreover I show a node which has a button which needs to be behaved as a color picker after a drop has happened. so showing a static div at some position will not serve my task for a color picker type.

How you want to implement and style that color picker is up to you – each app will probably want to do something different.

That includes deciding where to show the color picker HTML and what property it will modify.

There are many different color pickers available. Note that if you use <input type="color">, you’ll get different results and behavior on different platforms.

I havent found a solution to implement color picker-> on a button click i showed a color picker div but that is also not clickable to show color options.
Doesnt a gojs button be extended as a color picker type?

For performance and flexibility, GoJS "Button"s are not HTML. Their implementation is given at http://gojs.net/latest/extensions/Buttons.js.

I’ve already pointed out the color picker in the Data Inspector used by the HTML Interaction sample.

i am understanding your point, in HTML Interaction there is a div and it pops up a color picker but inside a gojs node we have a button and I need to invoke a panel directly which has option to choose colors.->
I donot need a panel which is invoked by a button click, and again clicking on fill invokes a option to choose colors.

I also visited your all examples which is not of my help as you make a list of colors and on clicks you change the colors from list
function nextColor(c)

There is an unlimited number of apps that you can build – we cannot make samples for every possible combination of features.

You know how to implement a click handler on a node and access the clicked data, don’t you? There are lots of examples of that.

Remember to wrap your model or diagram modifying code in a transaction. That helps supports undo and makes sure everything is updated properly.