VideoDevices Property

Gets the video device collection object.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
Public Overridable ReadOnly Property VideoDevices As VideoDevices

'Usage
 
Dim instance As CaptureCtrl
Dim value As VideoDevices
 
value = instance.VideoDevices

public virtual VideoDevices VideoDevices {get;}

public:
virtual property VideoDevices^ VideoDevices {
   VideoDevices^ get();
}

Property Value

A VideoDevices collection object.

Remarks

The VideoDevices object is used to enumerate the available video capture devices.

Example

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools
Imports Leadtools.Multimedia
Imports LeadtoolsMultimediaExamples.Fixtures

Public _result As Boolean = False
Public _form As CaptureCtrlForm = New CaptureCtrlForm()
Public _capturectrl As CaptureCtrl
Public _csbform As TestCtrlSubForm
Public Sub DevicesExample()
   ' reference the capture control
   _capturectrl = _form.CaptureCtrl

   ' input file
   Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "CaptureCtrl_Source.avi")

   Try
      ' create the sub form for devices listbox
      _csbform = New TestCtrlSubForm()

      AddHandler _csbform.Load, AddressOf Form_Load
      AddHandler _csbform.buttonRefresh.Click, AddressOf Refresh_Click
      AddHandler _csbform.List.Click, AddressOf List_Click

      ' show the devices form
      _csbform.ShowDialog()

      ' get the selected device index
      Dim selectedRenderer As Integer = _capturectrl.AudioDevices.Selection

      ' set the result to what we expect 
      _result = (Not _csbform.List.SelectedItem Is Nothing AndAlso _capturectrl.AudioDevices.Selection <> -1)
   Catch e1 As Exception
      _result = False
   End Try
End Sub

Private Sub Form_Load(ByVal sender As Object, ByVal e As EventArgs)
   '  build the audio device list
   EnumerateDevices(_capturectrl.AudioDevices, _csbform.List)
End Sub

Private Sub List_Click(ByVal sender As Object, ByVal e As EventArgs)
   '  select the audio device
   SelectRenderer(_capturectrl.AudioDevices, _csbform.List)
End Sub

Private Sub Refresh_Click(ByVal sender As Object, ByVal e As EventArgs)
   '  refresh audio devices
   RefreshDevices(_capturectrl.AudioDevices, _csbform.List)
End Sub

Private Sub EnumerateDevices(ByVal Devices As AudioDevices, ByVal List As ListBox)
   '  Build the devices list box
   Dim Selected As Integer = -1

   ' empty the list box
   List.Items.Clear()

   ' add the available audio devices to the list box
   Dim i As Integer = 0
   Do While (i <= (Devices.Count - 1))
      List.Items.Add(Devices(i))
      If Devices(i).Selected Then
         Selected = i
      End If
      i += 1
   Loop
   '  highlight the current selection
   List.SelectedIndex = Selected
End Sub

Private Sub RefreshDevices(ByVal Devices As AudioDevices, ByVal List As ListBox)
   Dim SelectedName As String = String.Empty

   '  save the currently selected device's name
   If Devices.Selection >= 0 Then
      SelectedName = Devices(Devices.Selection).FriendlyName
   End If

   '  refresh the device collection
   Devices.Reset()

   '  if there was a previously selected renderer, reselect it
   If SelectedName <> String.Empty Then
      Devices.Selection = Devices.IndexOf(SelectedName)
   End If

   '  rebuild the listbox
   EnumerateDevices(Devices, List)
End Sub

Private Sub SelectRenderer(ByVal Devices As AudioDevices, ByVal List As ListBox)
   '  select the highlighted device
   Devices.Selection = Devices.IndexOf(TryCast(List.Items(List.SelectedIndex), Device))
End Sub

Public NotInheritable Class LEAD_VARS
Public Const MediaDir As String = "C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 18\Media"
End Class

using Leadtools;
using Leadtools.Multimedia;
using LeadtoolsMultimediaExamples.Fixtures;

public bool _result = false;
public CaptureCtrlForm _form = new CaptureCtrlForm();
public CaptureCtrl _capturectrl;
public TestCtrlSubForm _csbform;
public void DevicesExample()
{
   // reference the capture control
   _capturectrl = _form.CaptureCtrl;

   // input file
   string outFile =Path.Combine(LEAD_VARS.MediaDir,"CaptureCtrl_Source.avi");

   try
   {
      // create the sub form for devices listbox
      _csbform = new TestCtrlSubForm();

      _csbform.Load += new EventHandler(Form_Load);
      _csbform.buttonRefresh.Click += new EventHandler(Refresh_Click);
      _csbform.List.Click += new EventHandler(List_Click);

      // show the devices form
      _csbform.ShowDialog();

      // get the selected device index
      int selectedRenderer = _capturectrl.AudioDevices.Selection;

      // set the result to what we expect 
      _result = (_csbform.List.SelectedItem != null && _capturectrl.AudioDevices.Selection != -1);
   }
   catch (Exception)
   {
      _result = false;
   }
}

void Form_Load(object sender, EventArgs e)
{
   //  build the audio device list
   EnumerateDevices(_capturectrl.AudioDevices, _csbform.List);
}

void List_Click(object sender, EventArgs e)
{
   //  select the audio device
   SelectRenderer(_capturectrl.AudioDevices, _csbform.List);
}

void Refresh_Click(object sender, EventArgs e)
{
   //  refresh audio devices
   RefreshDevices(_capturectrl.AudioDevices, _csbform.List);
}

void EnumerateDevices(AudioDevices Devices, ListBox List)
{
   //  Build the device's list box
   int Selected = -1;

   // empty the list box
   List.Items.Clear();

   // add the available audio devices to the list box
   for (int i = 0; (i <= (Devices.Count - 1)); i++)
   {
      List.Items.Add(Devices[i]);
      if (Devices[i].Selected)
      {
         Selected = i;
      }
   }
   //  highlight the current selection
   List.SelectedIndex = Selected;
}

void RefreshDevices(AudioDevices Devices, ListBox List)
{
   string SelectedName = string.Empty;

   //  save the currently selected device's name
   if (Devices.Selection >= 0)
      SelectedName = Devices[Devices.Selection].FriendlyName;

   //  refresh the device collection
   Devices.Reset();

   //  if there was a previously selected renderer, reselect it
   if (SelectedName != string.Empty)
      Devices.Selection = Devices.IndexOf(SelectedName);

   //  rebuild the listbox
   EnumerateDevices(Devices, List);
}

void SelectRenderer(AudioDevices Devices, ListBox List)
{
   //  select the highlighted device
   Devices.Selection = Devices.IndexOf(List.Items[List.SelectedIndex] as Device);
}

static class LEAD_VARS
{
public const string MediaDir = @"C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 18\Media";
}

Requirements

Target Platforms

Reference

CaptureCtrl Class
CaptureCtrl Members