Android Question Google TTS KEY_PARAM_PAN parameter implementation

Sub Class_Globals
    Private Root As B4XView
    Private xui As XUI
    Private tts As TTS
    Private Button1 As B4XView
End Sub

Public Sub Initialize
    
End Sub

Private Sub B4XPage_Created (Root1 As B4XView)
    Root = Root1
    Root.LoadLayout("MainPage")
    tts.Initialize("tts")
    Button1.Enabled = False
    Wait For TTS_Ready (Success As Boolean)
    Button1.Enabled = Success
End Sub

Private Sub Button1_Click
    Speak("test", CreateMap("pan": "1"))
End Sub

Private Sub Speak (Text As String, Params As Map)
    Dim jo As JavaObject = tts
    Dim map As JavaObject
    map.InitializeNewInstance("java.util.HashMap", Array(Params))
    jo.RunMethod("speak", Array(Text, 1, map))
End Sub

Private Sub SpeakWithVolume (TTSObject As TTS, Text As String, ClearQueue As Boolean, Volume As Float, Balance As Float)
    Dim vol As String = Volume
    Dim bal As String = Balance
    Dim queue As Int
    If ClearQueue Then queue = 0 Else queue = 1
  
    Dim m As JavaObject
    m.InitializeNewInstance("java.util.HashMap", Array(CreateMap("volume": vol, "pan": bal)))

    Dim jo As JavaObject = TTSObject
    jo.RunMethod("speak", Array(Text, queue, m))
End Sub

Private Sub SpeakWithVolume (TTSObject As TTS, Text As String, ClearQueue As Boolean, LeftVolume As Float, RightVolume As Float)
    Dim Volume As Float = Max(LeftVolume,RightVolume)
    If Volume=0 Then Return
    Dim Balance As Float = (RightVolume-LeftVolume)/Volume

    Dim Vol As String = Volume
    Dim Bal As String = Balance
    Dim queue As Int
    If ClearQueue Then queue = 0 Else queue = 1

    Dim m As JavaObject
    m.InitializeNewInstance("java.util.HashMap", Array(CreateMap("volume": Vol, "pan": Bal)))

    Dim jo As JavaObject = TTSObject
    jo.RunMethod("speak", Array(Text, queue, m))
End Sub