I came across this same problem last week. I am using a bar code scanner connected via bluetooth to a tablet. My application needs to allow the user to scan bar codes and then enter text. On a particular tablet, once the scanner was connected, the soft keyboard never displayed because the tablet assumed it was an external keyboard being connected. I found a work around by installing an application called "External Keyboard Helper" which lets you switch off the external keyboard so that the soft keyboard displays where necessary and yet the input from the scanner works as well.