Android ListActivity ArrayAdapter filtering with no physical keyboard?

I have a ListActivity based on an ArrayAdapter with setTextFilterEnabled set to true. This works fine on a device with a physical keyboard. Whe开发者_如何学Pythonn I start typing something on the keyboard, the items get filtered.

My question is how to get the same behavior on a device with no physical keyboard?

The user needs to long-tap the MENU button to bring up the soft keyboard. Then, AFAIK, filtering works as normal.

Note that I don't do much ListView filtering, so I'm basing this on my recollection of past discussions of this issue.