Sorry, I have concluded by further investigating this, that it is by design.
For example, if you check the ViewPort example
on your mobile device, you'll notice that you can't pinch-zoom with the smartphone browser's native functionality.
These events are captured and handled by ExtJS as a whole. There are the pinch, pinchstart and pinchend events
to handle it in the framework.
Additionally, we didn't add the recommended
to every example. If you run Ext.NET Examples in debug mode, you'll notice the console complaining about it.
In fact, if you add the recommended code for mobile compatibility to the infinite scrolling example you pointed, no pinch scrolling would happen in the page at all!
The code to properly (at least according to Sencha's design) set up a page to be mobile-friendly is:
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">
<ext:ResourcePlaceHolder runat="server" />
added to the
section of the HTML page. Notice the
below ensures Ext.NET will inject script resources after the meta tag, required for ExtJS to properly handle the setting.
Additionally, as you can see in the code snippet above, the main point on the meta viewport is exactly inhibit mobile browsers' own scaling (pinch-zooming), most likely this feature broke havoc on the mobile integration during its development and evolvement.
That said, and in brief: by design, ExtJS mobile support assumes you are drawing a responsive layout, appropriate for cellphone (or tablets) dimensions and lets you handle zoom/resize without letting cellphone default handlers to take place.
Well, I believe this is not really what you want to hear, but truth be said. Maybe you are still interested in trying to disable pinch interation by ExtJS at all and letting the mobile browser handle that?