The editor window displays the content of the file on which the
developer is currently working. What gets displayed in this location, however, is subject to
context. When editing code, for example, the code editor will appear. When working on a
user interface layout file, on the other hand, the user interface Designer tool will appear.
When multiple files are open, each file is represented by a tab located along the top edge
of the editor as shown in Figure 4-3.