JSFiddle - React, Tailwind, and code Playground

HTML

<button id="myButton">Click Me (using object scope)</button><br />
<button id="myButton2">Click Me (using global/window scope)</button>

JavaScript

var myObject = {
	say: function(message){
		alert(message);
	}
};

Ext.fly("myButton").on("click", function(event, element, options){
	this.say(options.message);
}, myObject, {
	message: "Hello World"
});

// Note: the default global scope in JavaScript is `window`.  `alert()` is actually
// a shortcut for `window.alert()`, so the following code will work.
Ext.fly("myButton2").on("click", function(event, element, options){
	this.alert(options.message);
}, this, {
	message: "Hello World"
});