On the 16th Feb 2010 Sencha announced the availability of the first Ext JS 4 Developer Preview. Definitely an exciting news for the Ext JS developers, I can see from the comments in Sencha Blog that people cannot wait for the release. This is the biggest overhaul to the framework. For those who worry about migration, the team has taken that into consideration.
Ext JS 4 is completely sandboxed; there is no more native object augmentation or reliance on global variables. This means you can run Ext JS 4 alongside Ext JS 3 on the same page. To demonstrate this we’ve taken the best of both versions and combined them in a single page. We’ve used the Desktop example from Ext JS 3 and loaded Ext JS 4’s brand new charts alongside as if they were part of Desktop itself – check it out for yourself.
The second step is to provide as strong a legacy layer as possible to help you upgrade your Ext JS 3.x applications. We’re starting that today with the release of a detailed overview guide to the differences between the versions, and will update this as we continue our rollout. In addition to the guide we will be providing a legacy file that can be dropped in to an Ext JS 3.x application to help you upgrade your app. We’ll be expanding on both of these in another post very soon. – Sencha Blog
The following articles highlights the key features in Ext JS 4;
- Ext JS 4 Dynamic Loading and New Class System
- Ext JS 4 Data Package
- Ext JS 4 Anatomy of a Model
- Ext JS 4 Preview Drawing and Charting
- Ext JS 4 Developer Preview
Ed Spencer from Sencha presented the introduction to Ext JS 4 and its architecture. You can see the slides below;
Last but not least, the examples and download is available;