IContainerControl Interface
Provides the functionality for a control to act as a parent for other controls.
For a list of all members of this type, see IContainerControl Members.
[Visual Basic] Public Interface IContainerControl [C#] public interface IContainerControl [C++] public __gc __interface IContainerControl [JScript] public interface IContainerControl
Classes that Implement IContainerControl
| Class | Description |
|---|---|
| ContainerControl | Provides focus management functionality for controls that can function as a container for other controls. |
Remarks
Notes to Implementers: Implement this interface in classes that you want to parent a collection of controls. The members of this interface allow you to activate a child control, or determine which control is currently active. When implemented in a class, ActivateControl takes a Control as a parameter and activates the specified control. The ActiveControl property activates or retrieves the control that is active.
In most common scenarios, you do not need to directly implement this interface. For example, if you create a Windows Control Library project, Visual Studio generates an initial class for you. That class inherits from the UserControl class, and UserControl implements IContainerControl for you.
Example
[Visual Basic, C#, C++] The following example inherits from the ScrollableControl class and implements the IContainerControl interface. Implementation is added to the ActiveControl property and the ActivateControl method.
[Visual Basic] Imports System Imports System.Windows.Forms Imports System.Drawing Public Class MyContainerControl Inherits ScrollableControl Implements IContainerControl Private myActiveControl As Control Public Sub New() ' Make the container control Blue so it can be distinguished on the form. Me.BackColor = Color.Blue ' Make the container scrollable. Me.AutoScroll = True End Sub ' Add implementation to the IContainerControl.ActiveControl property. Public Property ActiveControl() As Control Implements IContainerControl.ActiveControl Get Return Me.myActiveControl End Get Set ' Make sure the control is a member of the ControlCollection. If Me.Controls.Contains(value) Then Me.myActiveControl = value End If End Set End Property ' Add implementation to the IContainerControl.ActivateControl(Control) method. public Function ActivateControl(active As Control) As Boolean Implements IContainerControl.ActivateControl If Me.Controls.Contains(active) Then ' Select the control and scroll the control into view if needed. active.Select() Me.ScrollControlIntoView(active) Me.myActiveControl = active Return True End If Return False End Function End Class [C#] using System; using System.Windows.Forms; using System.Drawing; public class MyContainer : ScrollableControl, IContainerControl { private Control activeControl; public MyContainer() { // Make the container control Blue so it can be distinguished on the form. this.BackColor = Color.Blue; // Make the container scrollable. this.AutoScroll = true; } // Add implementation to the IContainerControl.ActiveControl property. public Control ActiveControl { get { return activeControl; } set { // Make sure the control is a member of the ControlCollection. if(this.Controls.Contains(value)) { activeControl = value; } } } // Add implementations to the IContainerControl.ActivateControl(Control) method. public bool ActivateControl(Control active) { if(this.Controls.Contains(active)) { // Select the control and scroll the control into view if needed. active.Select(); this.ScrollControlIntoView(active); this.activeControl = active; return true; } return false; } } [C++] using namespace System; using namespace System::Windows::Forms; using namespace System::Drawing; public __gc class MyContainer : public ScrollableControl, public IContainerControl { private: Control* activeControl; public: MyContainer() { // Make the container control Blue so it can be distinguished on the form. this->BackColor = Color::Blue; // Make the container scrollable. this->AutoScroll = true; } // Add implementation to the IContainerControl.ActiveControl property. __property Control* get_ActiveControl() { return activeControl; } __property void set_ActiveControl(Control* value) { // Make sure the control is a member of the ControlCollection. if (this->Controls->Contains(value)) { activeControl = value; } } // Add implementations to the IContainerControl.ActivateControl(Control) method. bool ActivateControl(Control* active) { if (this->Controls->Contains(active)) { // Select the control and scroll the control into view if needed. active->Select(); this->ScrollControlIntoView(active); this->activeControl = active; return true; } return false; } };
[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button
in the upper-left corner of the page.
Requirements
Namespace: System.Windows.Forms
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
See Also
IContainerControl Members | System.Windows.Forms Namespace | ContainerControl | Control