Guide applies to: modern
Your main view extends Ext.tab.Panel — it shows two tabs, a DataView of thumbnails and Grid of records
Your preview Dialog extends Ext.Dialog subclass, and has an instance of the +Video+ class embedded within it
There is a
controller
behind the event that creates the dialog when the user double-clicks on either a thumbnail from the dataview or a record from the grid
If you are new to Ext JS , or do not have an existing application, we recommend using the Sencha ExtGen npm package
to create a new Ext JS application. The steps to do so are in the next lab.