TreeView.ImageIndex Propriedade

Definição

Namespace:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Obtém ou define o valor de índice da lista de imagens da imagem padrão exibida pelos nós da árvore.

public:
 property int ImageIndex { int get(); void set(int value); };

[System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.TreeViewImageIndexConverter))]
public int ImageIndex { get; set; }

[System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.NoneExcludedImageIndexConverter))]
[System.Windows.Forms.RelatedImageList("ImageList")]
public int ImageIndex { get; set; }

[<System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.TreeViewImageIndexConverter))>]
member this.ImageIndex : int with get, set

[<System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.NoneExcludedImageIndexConverter))>]
[<System.Windows.Forms.RelatedImageList("ImageList")>]
member this.ImageIndex : int with get, set

Public Property ImageIndex As Integer

Valor da propriedade

Int32

Um valor de índice de base zero que representa a posição de um Image em um ImageList. O padrão é zero.

Atributos

TypeConverterAttribute RelatedImageListAttribute

Exceções

ArgumentOutOfRangeException

O índice especificado é menor que 0.

Exemplos

O exemplo de código a seguir cria e atribui um ImageList a um TreeView controle e preenche o TreeView controle com TreeNode objetos. Os nós de árvore são atribuídos imagens do ImageList que são exibidos quando em um estado selecionado ou não selecionado. Este exemplo exige que você tenha um Form que contenha um TreeViewe um ArrayList que contém Customer objetos que contêm Order objetos. Supõe-se também que os objetos e os Customer Order objetos são definidos.

ref class Customer
{
public:
   ArrayList^ CustomerOrders;
   String^ CustomerName;
   Customer( String^ myName )
   {
      CustomerName = myName;
      CustomerOrders = gcnew ArrayList;
   }

};

ref class Order
{
public:
   String^ OrderID;
   Order( String^ myOrderID )
   {
      this->OrderID = myOrderID;
   }

};

   void FillTreeView()
   {
      
      // Load the images in an ImageList.
      ImageList^ myImageList = gcnew ImageList;
      myImageList->Images->Add( Image::FromFile( "Default.gif" ) );
      myImageList->Images->Add( Image::FromFile( "SelectedDefault.gif" ) );
      myImageList->Images->Add( Image::FromFile( "Root.gif" ) );
      myImageList->Images->Add( Image::FromFile( "UnselectedCustomer.gif" ) );
      myImageList->Images->Add( Image::FromFile( "SelectedCustomer.gif" ) );
      myImageList->Images->Add( Image::FromFile( "UnselectedOrder.gif" ) );
      myImageList->Images->Add( Image::FromFile( "SelectedOrder.gif" ) );
      
      // Assign the ImageList to the TreeView.
      myTreeView->ImageList = myImageList;
      
      // Set the TreeView control's default image and selected image indexes.
      myTreeView->ImageIndex = 0;
      myTreeView->SelectedImageIndex = 1;
      
      /* Set the index of image from the
        ImageList for selected and unselected tree nodes.*/
      this->rootImageIndex = 2;
      this->selectedCustomerImageIndex = 3;
      this->unselectedCustomerImageIndex = 4;
      this->selectedOrderImageIndex = 5;
      this->unselectedOrderImageIndex = 6;
      
      // Create the root tree node.
      TreeNode^ rootNode = gcnew TreeNode( "CustomerList" );
      rootNode->ImageIndex = rootImageIndex;
      rootNode->SelectedImageIndex = rootImageIndex;
      
      // Add a main root tree node.
      myTreeView->Nodes->Add( rootNode );
      
      // Add a root tree node for each Customer object in the ArrayList.
      IEnumerator^ myEnum = customerArray->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         Customer^ myCustomer = safe_cast<Customer^>(myEnum->Current);
         
         // Add a child tree node for each Order object.
         int countIndex = 0;
         array<TreeNode^>^myTreeNodeArray = gcnew array<TreeNode^>(myCustomer->CustomerOrders->Count);
         IEnumerator^ myEnum = myCustomer->CustomerOrders->GetEnumerator();
         while ( myEnum->MoveNext() )
         {
            Order^ myOrder = safe_cast<Order^>(myEnum->Current);
            
            // Add the Order tree node to the array.
            myTreeNodeArray[ countIndex ] = gcnew TreeNode( myOrder->OrderID,unselectedOrderImageIndex,selectedOrderImageIndex );
            countIndex++;
         }
         TreeNode^ customerNode = gcnew TreeNode( myCustomer->CustomerName,unselectedCustomerImageIndex,selectedCustomerImageIndex,myTreeNodeArray );
         myTreeView->Nodes[ 0 ]->Nodes->Add( customerNode );
      }
   }

public class Customer
{
   public ArrayList CustomerOrders;
   public string CustomerName;
   public Customer(string myName)
   {
      CustomerName = myName;
      CustomerOrders = new ArrayList(); 
   }
}
public class Order
{
   public string OrderID;
   public Order(string myOrderID )
   {
      this.OrderID = myOrderID;
   }
}

private void FillTreeView()
{
    // Load the images in an ImageList.
    ImageList myImageList = new ImageList();
    myImageList.Images.Add(Image.FromFile("Default.gif"));
    myImageList.Images.Add(Image.FromFile("SelectedDefault.gif"));
    myImageList.Images.Add(Image.FromFile("Root.gif"));
    myImageList.Images.Add(Image.FromFile("UnselectedCustomer.gif"));
    myImageList.Images.Add(Image.FromFile("SelectedCustomer.gif"));
    myImageList.Images.Add(Image.FromFile("UnselectedOrder.gif"));
    myImageList.Images.Add(Image.FromFile("SelectedOrder.gif"));
    
    // Assign the ImageList to the TreeView.
    myTreeView.ImageList = myImageList;
    
    // Set the TreeView control's default image and selected image indexes.
    myTreeView.ImageIndex = 0;
    myTreeView.SelectedImageIndex = 1;

    /* Set the index of image from the 
    ImageList for selected and unselected tree nodes.*/
    this.rootImageIndex = 2;
    this.selectedCustomerImageIndex = 3;
    this.unselectedCustomerImageIndex = 4;
    this.selectedOrderImageIndex = 5;
    this.unselectedOrderImageIndex = 6;
    
    // Create the root tree node.
    TreeNode rootNode = new TreeNode("CustomerList");
    rootNode.ImageIndex = rootImageIndex;
    rootNode.SelectedImageIndex = rootImageIndex;
      
    // Add a main root tree node.
    myTreeView.Nodes.Add(rootNode);

    // Add a root tree node for each Customer object in the ArrayList.
    foreach(Customer myCustomer in customerArray)
    {
        // Add a child tree node for each Order object.
        int countIndex=0;
        TreeNode[] myTreeNodeArray = new TreeNode[myCustomer.CustomerOrders.Count];
        foreach(Order myOrder in myCustomer.CustomerOrders)
        {
            // Add the Order tree node to the array.
            myTreeNodeArray[countIndex] = new TreeNode(myOrder.OrderID,
              unselectedOrderImageIndex, selectedOrderImageIndex);
            countIndex++;
        }
        // Add the Customer tree node.
        TreeNode customerNode = new TreeNode(myCustomer.CustomerName,
            unselectedCustomerImageIndex, selectedCustomerImageIndex, myTreeNodeArray);
        myTreeView.Nodes[0].Nodes.Add(customerNode);
    }
}

Public Class Customer
   Public CustomerOrders As ArrayList
   Public CustomerName As String
   
   Public Sub New(myName As String)
      CustomerName = myName
      CustomerOrders = New ArrayList()
   End Sub
End Class


Public Class Order
   Public OrderID As String
   
   Public Sub New(myOrderID As String)
      Me.OrderID = myOrderID
   End Sub
End Class

Private Sub FillTreeView()
   ' Load the images in an ImageList.
   Dim myImageList As New ImageList()
   myImageList.Images.Add(Image.FromFile("Default.gif"))
   myImageList.Images.Add(Image.FromFile("SelectedDefault.gif"))
   myImageList.Images.Add(Image.FromFile("Root.gif"))
   myImageList.Images.Add(Image.FromFile("UnselectedCustomer.gif"))
   myImageList.Images.Add(Image.FromFile("SelectedCustomer.gif"))
   myImageList.Images.Add(Image.FromFile("UnselectedOrder.gif"))
   myImageList.Images.Add(Image.FromFile("SelectedOrder.gif"))
   
   ' Assign the ImageList to the TreeView.
   myTreeView.ImageList = myImageList
   
   ' Set the TreeView control's default image and selected image indexes.
   myTreeView.ImageIndex = 0
   myTreeView.SelectedImageIndex = 1
   
   ' Set the index of image from the 
   ' ImageList for selected and unselected tree nodes.
   Me.rootImageIndex = 2
   Me.selectedCustomerImageIndex = 3
   Me.unselectedCustomerImageIndex = 4
   Me.selectedOrderImageIndex = 5
   Me.unselectedOrderImageIndex = 6
   
   ' Create the root tree node.
   Dim rootNode As New TreeNode("CustomerList")
   rootNode.ImageIndex = rootImageIndex
   rootNode.SelectedImageIndex = rootImageIndex
   
   ' Add a main root tree node.
   myTreeView.Nodes.Add(rootNode)
   
   ' Add a root tree node for each Customer object in the ArrayList.
   Dim myCustomer As Customer
   For Each myCustomer In  customerArray
      ' Add a child tree node for each Order object.
      Dim countIndex As Integer = 0
      Dim myTreeNodeArray(myCustomer.CustomerOrders.Count) As TreeNode
      Dim myOrder As Order
      For Each myOrder In  myCustomer.CustomerOrders
         ' Add the Order tree node to the array.
         myTreeNodeArray(countIndex) = New TreeNode(myOrder.OrderID, _
            unselectedOrderImageIndex, selectedOrderImageIndex)
         countIndex += 1
      Next myOrder
      ' Add the Customer tree node.
      Dim customerNode As New TreeNode(myCustomer.CustomerName, _
         unselectedCustomerImageIndex, selectedCustomerImageIndex, myTreeNodeArray)
      myTreeView.Nodes(0).Nodes.Add(customerNode)
   Next myCustomer
End Sub

Comentários

O ImageIndex valor é o índice de um Image armazenado na ImageList propriedade atribuída ImageList .

ImageKey e ImageIndex são mutuamente exclusivos, ou seja, se um for definido, o outro será definido como um valor inválido e ignorado. Se você definir a ImageKey propriedade, a ImageIndex propriedade será definida automaticamente como -1. Como alternativa, se você definir a ImageIndex propriedade, ela ImageKey será definida automaticamente como uma cadeia de caracteres vazia ("").

Observação

Ao definir a ImageIndex propriedade em tempo de execução, o TreeView identificador é recriado (consulte Control.RecreateHandle) para atualizar a aparência do controle. Isso faz com que todos os nós de árvore sejam recolhidos, com exceção do selecionado TreeNode.