for when somebody is interested. it turned out to be not so complex. i just tested a bit here is the script. the examples changes the search in two different smartlists. one to show just the song that is playing (i did this before by cleaning a playlist and adding it) and one that gives all the songs that have the same genre (genres is a list field).
Sub PLNSong(ByVal Nummer As String)
Dim PlaylistNo As Integer
Dim Regel As String
PlaylistNo = 172836362
Regel = "[Filename]=[" & Nummer & "]"
Dim PlayL As MediaCenter.IMJPlaylistAutomation
PlayL = mediaCenterRef.GetPlaylistByID(PlaylistNo)
PlayL.Set("Search", Regel)
End Sub
Sub PLNGenre(ByVal genre As String)
Dim PlaylistNo As Integer
Dim Regel As String
PlaylistNo = 805778929
Regel = "[Media Type]=[Audio] [genres]=" & genre
Dim PlayL As MediaCenter.IMJPlaylistAutomation
PlayL = mediaCenterRef.GetPlaylistByID(PlaylistNo)
PlayL.Set("Search", Regel)
End Sub
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gab