It may not be clear in the documentation that the onDisplayCompletions callback is only valid for completed applications. There is no internal dictionary in the Android database to suggest words based on what you type, that is, an input / input method method; but there is support for completing applications, and this is what you are watching right now.
So the example does this, but you should use an application that offers material. Most text fields will not.
An example application is Facebook. If you install the Facebook app, go to "Messages", click "To," and turn the device to the side. Then enter the beginning of the friendβs name and you will see how the name of your friends appears in the completion list.
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