In the previous article from this series I've explored the main controls that support the new user experience in metro style applications. GridView, ListView and FlipView are a big help to fully embrace the metro-styled experience and having a deep knowledge about their features is important to develop effective applications. In this number I would want to go for two advanced features I've skipped in the introduction. I'm referring to Semantic Zoom, that is the ability to coordinate the content of two controls to easily explore a collection, and to Incremental Loading that let you load items in chunks when they really need.
When you think at zooming something, you probably recall to your mind how you zoom a map in google or bing, or probably how you zoom an image or a document.
These kinds of zoom go under the name of "optical" zoom, because you are enlarging your optical view of an element as you were using a lens. If you think at a GridView, or also at a ListView, you easily understand that optical zoom cannot be applied just because it does have a real importance. What you can try to zoom instead, are the groups you defined for your view. In the case you have a number of items in your grid it may be difficult to scroll and scroll just to reach the item you are searching for, but probably you know what is the group it belongs to, so you can zoom out to the groups, select the group and then zoom in again to the items in the group. This is the so-called semantic zoom, a zoom that does not imply an optical enlargement but that is based on the semantic of your grouping.