Selecting ltmmPlayCtrl Processors Example for Visual Basic

The following code demonstrates how to enumerate and select ltmmPlayCtrl processors:

Sub BuildRegisteredList(Processors As ltmmProcessors, List As ListBox) 
    ' rebuild the registered processor listbox
    List.Clear
    For i = 0 To (Processors.Count - 1) 
        List.AddItem Processors.Item (i).FriendlyName
        List.ItemData(List.NewIndex) = i
    Next
End Sub
Sub BuildSelectedList(Processors As ltmmProcessors, List As ListBox) 
    ' rebuild the selected processor listbox
    List.Clear
    For i = 0 To (Processors.Count - 1) 
        List.AddItem Processors.Item (i).FriendlyName
    Next
    List.AddItem ""
    List.Selected(List.ListCount - 1) = True
End Sub
Sub AddProcessor(prcRegistered As ltmmProcessors, lstRegistered As ListBox, prcSelected As ltmmProcessors, lstSelected As ListBox) 
    ' inserts the highlighted registered processor into the selected processor list
    prcSelected.Add prcRegistered.Item(lstRegistered.ItemData(lstRegistered.ListIndex)), lstSelected.ListIndex
    lstSelected.AddItem lstRegistered.List(lstRegistered.ListIndex), lstSelected.ListIndex
End Sub
Sub RemoveAllProcessors(Processors As ltmmProcessors, List As ListBox) 
    ' removes all of the selected processors

    Processors.RemoveAll
    BuildSelectedList Processors, List
End Sub
Sub RemoveProcessor(Processors As ltmmProcessors, List As ListBox) 
    ' removes the highlighted selected processors
    Dim Index As Integer
    Index = List.ListIndex
    Processors.Remove Index
    List.RemoveItem Index
    List.Selected(Index) = True
End Sub

Sub RefreshProcessors(Processors As ltmmProcessors, List As ListBox) 
    ' refreshes the registered processor collection
    Dim Index As Integer
    Dim Selected As String
    Dim Found As Long
    
    Index = List.ListIndex
    If Index >= 0 Then
        ' save the currently selected item for later search
        Selected = Processors.Item (List.ItemData(Index)).Name
    End If
    Processors.Refresh
    BuildRegisteredList Processors, List
    If Index >= 0 Then
        ' reselect the processor
        Found = Processors.Find (Selected) 
        If Found >= 0 Then
            For i = 0 To (List.ListCount - 1) 
                If List.ItemData(i) = Found Then
                    List.Selected(i) = True
                    Exit For
                End If
            Next
        End If
    End If
End Sub
Sub ProcessorProperties(Processors As ltmmProcessors, List As ListBox) 
    ' show the selected processors properties dialog box
    Processors.Item (List.ListIndex).ShowDialog ltmmProcessor_Dlg_Properties, hWnd
End Sub

Sub RegisteredIndexChanged(Processors As ltmmProcessors, List As ListBox, cmdAdd As CommandButton) 
    ' enable buttons based on the current state of the registered processor listbox
    Dim Index As Integer
    Index = List.ListIndex
    If Index >= 0 Then
        cmdAdd.Enabled = True
    Else
        cmdAdd.Enabled = False
    End If
End Sub
Sub SelectedIndexChanged(Processors As ltmmProcessors, List As ListBox, cmdRemove As CommandButton, cmdRemoveAll As CommandButton, cmdProperties As CommandButton) 
    ' enable buttons based on the current state of the selected processor listbox
    Dim Index As Integer
    Index = List.ListIndex
    If Index >= 0 And Index < (List.ListCount - 1) Then
        cmdRemove.Enabled = True
        cmdProperties.Enabled = Processors.Item (Index).HasDialog (ltmmProcessors_Dlg_Properties) 
       
    Else
        cmdRemove.Enabled = False
        cmdProperties.Enabled = False
    End If
    cmdRemoveAll.Enabled = (List.ListCount > 1) 
End Sub

Private Sub cmdAudioAdd_Click()
    ' add audio processor
    AddProcessor ltmmPlayCtrl1.AudioProcessors, lstAudioRegistered, ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected
    SelectedIndexChanged ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected, cmdAudioRemove, cmdAudioRemoveAll, cmdAudioProperties
End Sub

Private Sub cmdAudioProperties_Click()
    ' show audio properties
    ProcessorProperties ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected
End Sub

Private Sub cmdAudioRefresh_Click()
    ' refresh audio processors
    RefreshProcessors ltmmPlayCtrl1.AudioProcessors, lstAudioRegistered
    RegisteredIndexChanged ltmmPlayCtrl1.AudioProcessors, lstAudioRegistered, cmdAudioAdd
End Sub

Private Sub cmdAudioRemove_Click()
    ' remove audio processor
    RemoveProcessor ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected
    SelectedIndexChanged ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected, cmdAudioRemove, cmdAudioRemoveAll, cmdAudioProperties
End Sub

Private Sub cmdAudioRemoveAll_Click()
    ' remove all audio processors
    RemoveAllProcessors ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected
    SelectedIndexChanged ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected, cmdAudioRemove, cmdAudioRemoveAll, cmdAudioProperties
End Sub

Private Sub cmdVideoAdd_Click()
    ' add video processor
    AddProcessor ltmmPlayCtrl1.VideoProcessors, lstVideoRegistered, ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected
    SelectedIndexChanged ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected, cmdVideoRemove, cmdVideoRemoveAll, cmdVideoProperties
End Sub

Private Sub cmdVideoProperties_Click()
    ' show video properties
    ProcessorProperties ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected
End Sub

Private Sub cmdVideoRefresh_Click()
    ' refresh video processors
    RefreshProcessors ltmmPlayCtrl1.VideoProcessors, lstVideoRegistered
    RegisteredIndexChanged ltmmPlayCtrl1.VideoProcessors, lstVideoRegistered, cmdVideoAdd
End Sub

Private Sub cmdVideoRemove_Click()
    ' remove video processor
    RemoveProcessor ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected
    SelectedIndexChanged ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected, cmdVideoRemove, cmdVideoRemoveAll, cmdVideoProperties
End Sub

Private Sub cmdVideoRemoveAll_Click()
    ' remove all video processors
    RemoveAllProcessors ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected
    SelectedIndexChanged ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected, cmdVideoRemove, cmdVideoRemoveAll, cmdVideoProperties
End Sub

Private Sub Form_Load()
    ' build audio processor lists
    BuildRegisteredList ltmmPlayCtrl1.AudioProcessors, lstAudioRegistered
    RegisteredIndexChanged ltmmPlayCtrl1.AudioProcessors, lstAudioRegistered, cmdAudioAdd
    BuildSelectedList ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected
    SelectedIndexChanged ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected, cmdAudioRemove, cmdAudioRemoveAll, cmdAudioProperties

    ' build video processor lists
    BuildRegisteredList ltmmPlayCtrl1.VideoProcessors, lstVideoRegistered
    RegisteredIndexChanged ltmmPlayCtrl1.VideoProcessors, lstVideoRegistered, cmdVideoAdd
    BuildSelectedList ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected
    SelectedIndexChanged ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected, cmdVideoRemove, cmdVideoRemoveAll, cmdVideoProperties

End Sub

Private Sub lstAudioRegistered_Click()
    ' update audio buttons
    RegisteredIndexChanged ltmmPlayCtrl1.AudioProcessors, lstAudioRegistered, cmdAudioAdd
End Sub

Private Sub lstAudioSelected_Click()
    ' update audio buttons
    SelectedIndexChanged ltmmPlayCtrl1.SelectedAudioProcessors, lstAudioSelected, cmdAudioRemove, cmdAudioRemoveAll, cmdAudioProperties
End Sub

Private Sub lstVideoRegistered_Click()
    ' update video buttons
    RegisteredIndexChanged ltmmPlayCtrl1.VideoProcessors, lstVideoRegistered, cmdVideoAdd
End Sub

Private Sub lstVideoSelected_Click()
    ' update video buttons
    SelectedIndexChanged ltmmPlayCtrl1.SelectedVideoProcessors, lstVideoSelected, cmdVideoRemove, cmdVideoRemoveAll, cmdVideoProperties
End Sub