the picker panel should be attached to a view (ex. a label, a small panel..) and then instructed about the direction toward expand itself.
Possible directions are (extracted by library code):
Dim pck_DIR_BOTTOM = 0 As Byte
Dim pck_DIR_TOP = 1 As Byte
Dim pck_DIR_RIGHT = 2 As Byte
Dim pck_DIR_LEFT = 3 As Byte
Here it is an example on how to expand it on the left of a given label
B4X:
dgpicker.setAnchorView(lbl, dgpicker.pck_DIR_LEFT) 'anchor picker to desidered view
You may want to experiment with the sample code provided along with the library, changing parameters to see the resulting effect.
For a real-word usage of the library, check the configuration section of my mini-game 15Tiles.
Let me know if you need further assistance and thank you for your interest in my lib.