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By Default you will not be able to see the mixins property in the inspector of the View, and if you try to add it as custom it will show “Attempted to add a property that already exist”.

But you can do one thing:

<ol><li>Right click on the view and “Promote to class” and it will create another js inside the projects.</li><li>Go again to the View and see the new property in the  inspector “mixins”</li><li>Add the properties you want to mix.</li></ol>Mixins Value Example:

<pre style="background-image: URL(http://2.bp.blogspot.com/_z5ltvMQPaa8/SjJXr_U2YBI/AAAAAAAAAAM/46OqEP32CJ8/s320/codebg.gif); background: #f0f0f0; border: 1px dashed #CCCCCC; color: black; font-family: arial; font-size: 12px; height: auto; line-height: 20px; overflow: auto; padding: 0px; text-align: left; width: 99%;"> {
dragSelector: 'Ext.ux.DataView.DragSelector',
draggable : 'Ext.ux.DataView.Draggable'
}
</pre>
And thats all…