A specialized container representing the viewable application area (the browser viewport).
The Viewport renders itself to the document body, and automatically sizes itself to the size of
the browser viewport and manages window resizing. There may only be one Viewport created
in a page.
Like any Container, a Viewport will only perform sizing and positioning
on its child Components if you configure it with a layout.
A Common layout used with Viewports is border layout, but if the
required layout is simpler, a different layout should be chosen.
For example, to simply make a single child item occupy all available space, use
To display one "active" item at full size from a choice of several child items, use
Inner layouts are available because all Panels
added to the Viewport, either through its items, or the add
method of any of its child Panels may themselves have a layout.
The Viewport does not provide scrolling, so child Panels within the Viewport should provide
for scrolling if needed using the autoScroll config.
An example showing a classic application border layout:
html: '<h1 class="x-panel-header">Page Title</h1>',
margins: '0 0 5 0'
// could use a TreePanel or AccordionLayout for navigational items
title: 'South Panel',
html: 'Information goes here',
title: 'East Panel',
xtype: 'tabpanel', // TabPanel itself has no title
activeTab: 0, // First tab active by default
title: 'Default Tab',
html: 'The first tab\'s content. Others may be added dynamically'
true in this class to identify an object as an instantiated Viewport, or subclass thereof.
Defaults to: true