1. Ben Bimber, Ph.D. LabKey Software
ExtJS Migration Plan
Ben Bimber, Ph.D.
LabKey Software

2. ExtJS is a JavaScript framework
What is ExtJS?
ExtJS is a JavaScript framework
Library of widgets, utilities
ExtJS handles many cross-browser compatibility issues
Used in most newer LabKey pages
Creates dynamic, interactive UI
Most study redesign pages, timechart, etc.

3. LabKey includes ExtJS Version 3 ExtJS 4 was released earlier this year
Ext3->4 Migration
LabKey includes ExtJS Version 3
ExtJS 4 was released earlier this year
Many new features, not backwards compatible
We are migrating core pages to ExtJS 4
Change will be necessary for support of future browsers

4. Current state of LabKey Server:
General Timeline
Current state of LabKey Server:
Both Ext3 and Ext4 shipped with LabKey
Ext3 is automatically loaded on every page
LK Client API uses Ext3
Ext4 can be loaded on demand by specific pages
LabKey 13.2 (estimated late summer 2013)
All core pages migrated to use Ext4
Ext4 is loaded on every page
LK Client API uses Ext4
Ext3 can be loaded on demand by specific pages

5. How Does This Impact Me?
If you do not have custom pages, this transition should not require any changes
LabKey will migrate and test core pages
If you are unsure, you probably have not used Ext
If you have custom pages that use Ext3, you will need to either update pages to Ext4 or declare Ext3 dependency

6. How Do I Prepare For This?
Consider writing any new pages using Ext4
For majority of applications, Ext4 has only minor differences
Future-proof existing that use Ext3 pages by declaring that dependency
We now recommend that if a custom page uses Ext, that it explicitly load the proper Ext version
Doing so means your page will continue to work during any Ext version changes

7. There are 2 ways to declare Ext dependencies:
Loading Ext Versions
There are 2 ways to declare Ext dependencies:
Within JavaScript, using:
LABKEY.requiresExt4Sandbox();
LABKEY.requiresExt3();
If using a file-based module, we now support declaring dependencies in the view.xml file
See online documentation:

8. Majority of our JavaScript Client API will not change
LabKey Client API
Majority of our JavaScript Client API will not change
Classes that extend Ext will change:
LABKEY.ext.EditorGrid
LABKEY.ext.FormPanel
LABKEY.ext.Store
We are developing Ext4 versions
Will publically released in coming versions
Pre-public versions can be used, with the caveat that they may change
Can load using LABKEY.requiresExt4ClientAPI() in JavaScript
Also by declaring dependency on “Ext4ClientApi” in the view.xml file

9. Survey any custom pages in your site
Suggested Steps
Survey any custom pages in your site
Contact LabKey if you have questions on the process

10. Ext4 Development in LabKey:
Additional Resources
Ext4 Development in LabKey:
Declaring JS Dependencies:
ExtJS Docs