Extjs Script is not working: throws Exception

/**
 * Rajan Y. Rawal
 * application.js
 * This file is sample file for learing Extjs
 */

// reference local blank image
Ext.BLANK_IMAGE_URL = '../extjs/resources/images/default/s.gif';

// create namespace
Ext.namespace('myNameSpace');

// Just to allow this tutorial to work for 1.1 and 2.
//Ext.Ext2 = (Ext.version && (Ext.version.indexOf("2") == 0));

// create application
    myNameSpace.app = function() {
    var btn1;
    var privVar1 = 11;
    var btn1Handler = function(button, event) {
        alert('privVar1=' + privVar1);
        alert('this.btn1Text=' + this.btn1Text);
    };

    return {
        // public properties, e.g. strings to translate
        btn1Text: 'Button 1',

        // public methods
        init: function() {
                btn1 = new Ext.Button('btn1-ct', {
                    text: this.btn1Text,
                    handler: btn1Handler,
                    scope:this
                });
        }
    };
}();
Ext.apply(myNameSpace.app, {
    btn1Text:'Taste 1',
    init: function() {
        try {
           开发者_高级运维 btn1 = new Ext.Button('btn1-ct', {
                text: this.btn1Text,
                handler: btn1Handler,
                scope: this
            });
        }
        catch(e) {
            alert('Error: "' + e.message + '" at line: ' + e.lineNumber);
        }
    }
});

Where is my fault?

---

Your script is working. What exactly are you expecting it to do?

You're creating an Ext.button with a handler, but there it is not being told to render anywhere on the page. You should provide a renderTo config option which will tell ExtJS to render the button to a given element...

            btn1 = new Ext.Button('btn1-ct', {
                text: this.btn1Text,
                handler: btn1Handler,
                scope: this,
                renderTo: 'element-of-html-div'
            });

Also, you're defining and then overriding everything in myNameSpace.app, this is pointless.