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Knowledge Base / Collapsible menu from Demo application
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Collapsible menu from Demo application

Updated on Sep 15, 2025

Environment

Date PostedProductAuthor
March 27, 2015RadCollapsiblePanel for WinFormsDesislava Yordanova

Problem

This article demonstrates how to achieve the collapsible menu from the Demo application.

collapsiblemenudemoapplication

Solution

Firstly, you should create a new project with a RadForm. Afterwards, drag a RadCollapsiblePanel and a RadPanorama from the Toolbox and drop them onto the form. You need to insert a RadListControl in the RadCollapsiblePanel.

Then, you should change the RadCollapsiblePanel.ExpandDirection to Right and customize its style by changing the header font, fore color, rotate the text etc*.*We should apply a specific image to the HeaderButtonElement for the expanded and collapsed state. We will use LightVisualElement s for the up and down arrows added to the CollapsiblePanelElement.HeaderElement.Children collection. In order to customize the RadListControl, we can use the VisualItemFormatting event.

C#
Font font = new Font("Arial", 14f);
Font itemsFont = new Font("Arial", 11f);
 
public Form1()
{
    InitializeComponent();
 
    this.BackColor = Color.White;
 
    this.radCollapsiblePanel1.Width = 250;
    this.radCollapsiblePanel1.Dock = DockStyle.Left;
    this.radCollapsiblePanel1.ExpandDirection = Telerik.WinControls.UI.RadDirection.Right;
   
    this.radPanorama1.Dock = DockStyle.Fill;
    this.radPanorama1.PanoramaElement.BackColor = Color.Transparent;
  
    this.radCollapsiblePanel1.HeaderText = "ALL CONTROLS";
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.Margin = new Padding(0, 0, -5, 0);
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderTextElement.AngleTransform = 180;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderTextElement.Font = font;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderTextElement.ForeColor = Color.White;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderTextElement.StretchHorizontally = true;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderTextElement.StretchVertically = true;
    this.radCollapsiblePanel1.CollapsiblePanelElement.ShowHeaderLine = false;
    this.radCollapsiblePanel1.ControlsContainer.PanelElement.Border.Visibility = Telerik.WinControls.ElementVisibility.Collapsed;
 
    this.radCollapsiblePanel1.Collapsed += radCollapsiblePanel1_Collapsed;
    this.radCollapsiblePanel1.Expanded += radCollapsiblePanel1_Expanded;
 
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderButtonElement.MinSize = new Size(40, 40);
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderButtonElement.Image = Properties.Resources.chevron_left;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderButtonElement.ImageLayout = ImageLayout.Zoom;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderButtonElement.Shape = null;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderButtonElement.DrawFill = false;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderButtonElement.DrawBorder = false;
     
    Color greenColor = Color.FromArgb(55, 155, 83);
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.BackColor = greenColor;
    this.radCollapsiblePanel1.PanelContainer.BackColor = greenColor;
    this.radCollapsiblePanel1.PanelContainer.Margin = new Padding(20, 0, 0, 0);
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.GradientStyle = Telerik.WinControls.GradientStyles.Solid;
 
    LightVisualElement upButton = new LightVisualElement();
    upButton.StretchVertically = false;
    upButton.MaxSize = upButton.MinSize = new System.Drawing.Size(50, 35);
    upButton.Click += upButton_Click;
    upButton.Image = Properties.Resources.arrow_up;
    upButton.MouseEnter += upButton_MouseEnter;
    upButton.MouseLeave += upButton_MouseLeave;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.Children.Add(upButton);
 
    LightVisualElement downButton = new LightVisualElement();
    downButton.StretchVertically = false;
    downButton.MaxSize = downButton.MinSize = new System.Drawing.Size(50, 35);
    downButton.Click += downButton_Click;
    downButton.Image = Properties.Resources.arrow_down;
    downButton.MouseEnter += downButton_MouseEnter;
    downButton.MouseLeave += downButton_MouseLeave;
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.Children.Add(downButton);
   
    radListControl1.ListElement.BackColor = Color.Transparent;
  
    radListControl1.ItemHeight = 40;
    radListControl1.VisualItemFormatting += listControl_VisualItemFormatting;
    radListControl1.Dock = DockStyle.Fill;
    radListControl1.ListElement.DrawBorder = false;
    for (int i = 0; i < 50; i++)
    {
        radListControl1.Items.Add("Item" + i);
    }
    radListControl1.ListElement.Scroller.ScrollState = ScrollState.AlwaysHide;
    radListControl1.SelectedIndexChanged += radListControl1_SelectedIndexChanged;
    this.radCollapsiblePanel1.PanelContainer.Controls.Add(radListControl1);
}
 
private void radListControl1_SelectedIndexChanged(object sender, Telerik.WinControls.UI.Data.PositionChangedEventArgs e)
{
    this.radPanorama1.Items.Clear();
    for (int i = 0; i < 5; i++)
    {
        RadTileElement tile = new RadTileElement();
        tile.Text = "Tile" + e.Position + "." + i;
        this.radPanorama1.Items.Add(tile);
    }
}
 
private void radCollapsiblePanel1_Expanded(object sender, EventArgs e)
{
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderButtonElement.Image = Properties.Resources.chevron_left;
}
 
private void radCollapsiblePanel1_Collapsed(object sender, EventArgs e)
{
    this.radCollapsiblePanel1.CollapsiblePanelElement.HeaderElement.HeaderButtonElement.Image = Properties.Resources.chevron_right;
}
 
private void downButton_Click(object sender, EventArgs e)
{
    DoScrollList(false);
}
 
private void upButton_Click(object sender, EventArgs e)
{
    DoScrollList(true);
}
 
public void DoScrollList(bool scrollUp)
{
    if (scrollUp)
    {
        if (this.radListControl1.ListElement.VScrollBar.Value >= this.radListControl1.ListElement.ItemHeight)
        {
            this.radListControl1.ListElement.VScrollBar.Value -= this.radListControl1.ListElement.ItemHeight;
        }
        else
        {
            this.radListControl1.ListElement.VScrollBar.Value = 0;
        }
    }
    else
    {
        if (this.radListControl1.ListElement.VScrollBar.Value < this.radListControl1.ListElement.VScrollBar.Maximum -
            this.radListControl1.ListElement.VScrollBar.LargeChange)
        {
            int p = this.radListControl1.ListElement.VScrollBar.Value + this.radListControl1.ListElement.ItemHeight;
            p = Math.Min(p, this.radListControl1.ListElement.VScrollBar.Maximum - this.radListControl1.ListElement.VScrollBar.LargeChange);
            this.radListControl1.ListElement.VScrollBar.Value = p;
        }
    }
}
 
private void listControl_VisualItemFormatting(object sender, VisualItemFormattingEventArgs args)
{
    args.VisualItem.ForeColor = Color.White;
    args.VisualItem.Font = itemsFont;
    args.VisualItem.DrawBorder = true;
    args.VisualItem.BorderBoxStyle = Telerik.WinControls.BorderBoxStyle.FourBorders;
    args.VisualItem.BorderBottomWidth = 0.5f;
    args.VisualItem.BorderBottomColor = Color.White;
    args.VisualItem.BorderTopWidth = 0;
    args.VisualItem.BorderLeftWidth = 0;
    args.VisualItem.BorderRightWidth = 0;        
    args.VisualItem.DrawFill = false;
 
    if (args.VisualItem.Selected)
    {
        args.VisualItem.Image = Properties.Resources.active_tab_arrow_menu_1;
        args.VisualItem.ImageAlignment = ContentAlignment.MiddleRight;
        args.VisualItem.TextImageRelation = TextImageRelation.TextBeforeImage;
        args.VisualItem.GradientStyle = Telerik.WinControls.GradientStyles.Linear;
        args.VisualItem.DrawFill = true;
        args.VisualItem.BackColor = Color.FromArgb(26, 155, 86);
        args.VisualItem.BackColor2 = Color.FromArgb(24, 149, 81);
        args.VisualItem.BackColor3 = Color.FromArgb(21, 143, 74);
        args.VisualItem.BackColor4 = Color.FromArgb(20, 138, 70);
    }
    else
    {
        args.VisualItem.ResetValue(LightVisualElement.ImageProperty, Telerik.WinControls.ValueResetFlags.Local);
        args.VisualItem.ResetValue(LightVisualElement.TextImageRelationProperty, Telerik.WinControls.ValueResetFlags.Local);
        args.VisualItem.ResetValue(LightVisualElement.BackColorProperty, Telerik.WinControls.ValueResetFlags.Local);
        args.VisualItem.BackColor = Color.Transparent;
        args.VisualItem.GradientStyle = Telerik.WinControls.GradientStyles.Solid;
    }
}
 
private void downButton_MouseLeave(object sender, EventArgs e)
{
    LightVisualElement btn = sender as LightVisualElement;
    btn.Image = Properties.Resources.arrow_down;
}
 
private void downButton_MouseEnter(object sender, EventArgs e)
{
    LightVisualElement btn = sender as LightVisualElement;
    btn.Image = Properties.Resources.arrow_down_hover;
}
 
private void upButton_MouseLeave(object sender, EventArgs e)
{
    LightVisualElement btn = sender as LightVisualElement;
    btn.Image = Properties.Resources.arrow_up_hover;
}
 
private void upButton_MouseEnter(object sender, EventArgs e)
{
    LightVisualElement btn = sender as LightVisualElement;
    btn.Image = Properties.Resources.arrow_up;
}

A complete solution in C# and VB.NET can be found here.

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