Android Code Snippet [B4A] Capture hardware Key DOWN & Key UP with native OnKeyListener

I’m attaching a minimal snippet in case anyone needs reliable key DOWN & key UP detection in B4A—useful for shooter-style games or any scenario where you must avoid repeat triggers and don’t want to use any debounce/timer logic. It uses a native OnKeyListener and just logs the first DOWN (ignores repeats) and the UP.

' === Globals ===
Private KeyListener As Object

Sub Activity_Create(FirstTime As Boolean)
    InstallNativeKeyListener
End Sub

Private Sub InstallNativeKeyListener
    Dim jo As JavaObject = Activity
    jo.RunMethod("setFocusableInTouchMode", Array(True))
    jo.RunMethod("requestFocus", Null)
    ' Create the native OnKeyListener without writing inline Java
    KeyListener = jo.CreateEvent("android.view.View$OnKeyListener", "K", Null)
    jo.RunMethod("setOnKeyListener", Array(KeyListener))
End Sub

' Native handler: captures DOWN/UP and ignores autorepeat using getRepeatCount()
Private Sub K_Event (MethodName As String, Args() As Object) As Object
    ' Args = [View v, int keyCode, KeyEvent event]
    Dim keyCode As Int = Args(1)
    Dim ev As JavaObject = Args(2)
    Dim action As Int = ev.RunMethod("getAction", Null)        ' 0 = ACTION_DOWN, 1 = ACTION_UP
    Dim repeats As Int = ev.RunMethod("getRepeatCount", Null)  ' 0 on the first DOWN

    ' Example: use VOL+ (24) and ENTER (66) as shutter keys
    If keyCode = 24 Or keyCode = 66 Then
        If action = 0 Then                 ' ACTION_DOWN
            If repeats = 0 then
                   Log($"DOWN ${keyCode} rep=${repeats}"$)
            end if
            Return True
        Else If action = 1 Then            ' ACTION_UP
            Log($"UP ${keyCode}"$)
            Return True
        End If
    End If

    ' Other keys: don't consume
    Return False
End Sub