1) What is Ext Js?
Ext Js refers to Extended JavaScript. Ext JS is a JavaScript framework used to built interactive cross platform web application.
2) What are the features of Ext Js?
It is a JavaScript framework used to build enterprise application.
It includes MVC (Model View Control) and MVVM (Model View Viewmodel) design pattern.
It supports single page application development.
It's advance Data package allows it to easily retrieve of storing of data.
It support object oriented programming using JavaScript which makes easy application development and maintenance.
3) Name some tools used for Ext Js application development.
There are several popular tool used to develop Ext Js application.
Eclipse IDE.
Aptana.
Komodo.
WebStrom.
4) Explain life cycle of Ext Js.
Initialization: At this stage component event creation, registering with Ext.ComponentManager, calling initComponent method are done.
Rendering: At this stage creating the DOM for the component and adding it to the DOM hierarchy with the events, CSS are done.
Destruction: At this stage component are unregistered from Ext.ComponentManager, removing the events are done.
5) What is ExtJs component? Name some components.
Component is a group of DOM element used to build user interface od ExtJs application.
ComboBox.
Radio Button
Checkbox
TextField
Spinner
Text Area
Trigger
Chart
Label
Button
DateField
File Upload
Hidden Field
Number Field
Time Field
6) Explain why we choose Ext Js?
As the wide ranges of JavaScript libraries are available, it is important to choose the right one. Following are some important features provided by ExtJs.
ExtJs ibrary is the cross browser support.
Its documentation is very well maintained and comprehensive.
ExtJs framework supports Ajax implementations.
It supports integration with other Web server framework.
ExtJs framework has rich UI elements (component) provided.
It is provides excellent performance.
It is fully object oriented and follow design pattern like MVC and MVVM.
7) What are major Web browsers supported by ExtJs framework?
ExtJs supports all the modern browsers:
Windows Internet Explorer version 6 and later.
Mozilla Firefox version 1.5 and later.
Apple Safari version 2 and later.
Opera version 9 and later.
8) Can we integrate ExtJs with other web development server framework?
Yes, we can integrate ExtJs with other web development server, include Java language, PHP, Microsoft .NET, Ruby on Rails, and ColdFusion.
9) Explain extjs decode()?
var json = Ext.decode(response.responseText);
Ext.Msg.alert('Error', json.error);
10) How to implement pagination in grid panel?
Ext.PagingToolbar plugin is used to implement pagination in grid panel.
Example:
new Ext.PagingToolbar({
pageSize: 20,
store: store,
displayInfo: true,
displayMsg: 'Displaying topics {0} - {1} of {2}',
emptyMsg: "No topics to display",
})
// trigger the data store load
store.load({params:{start:0, limit:25}});
11) What is the purpose of MassageBox?
MessageBox is used to display different types of messagebox. It uses
Ext.window.MessageBox as a main class. We can create four types of message boxes:
-
- Alert.
Syntax:
Ext.Msg.alert():
Confirm.
Syntax:
Ext.Msg.confirm():
Prompt.
Syntax:
Ext.Msg.prompt():
Custom.
Syntax:
12) How to get record using id?
Syntax:
store.getById(String id);
13) How to get record using index?
Syntax:
store.getAt(Number index);
14) What is the purpose of loadData() in store?
loadData() is used for storing new records and replacing existing records from cache.
Syntax:
store.loadData(Object Object, Boolean boolean);
When the Boolean value passed in parameter is true it store new record and when it is false it replace existing record.
15) What is the purpose of load() in store?
It is used to load the data using proxies, which path are defined for services to fetch the backend data.
Syntax: