The following is an example of how FileInputOverlay's simple APIs can be tapped into, so you can build your own file input. For the file to actually upload, you'll need to have PHP enabled.
The main purpose behind FileInputOverlay is its ability to "attach" to buttons with as many different CSS styles as possible.
Below are tests for attaching to Dijit Buttons and a DIV. Some styles tested are inline, block, floats, margins and padding. See the test source code for the styles.
See the console for logging information.