windowsforms-devexpress-dot-xtranavbar-dot-navbarcontrol-2a741cc1.md
Allows you to assign a custom hint size before a hint is displayed in the VSToolBoxView paint style.
Namespace : DevExpress.XtraNavBar
Assembly : DevExpress.XtraNavBar.v25.2.dll
NuGet Package : DevExpress.Win
public event NavBarCalcHintSizeEventHandler CalcHintSize
Public Event CalcHintSize As NavBarCalcHintSizeEventHandler
The CalcHintSize event's data class is NavBarCalcHintSizeEventArgs. The following properties provide information specific to this event:
| Property | Description |
|---|---|
| Group | Gets the group for which the hint is displayed. Inherited from NavBarCustomHintEventArgs. |
| HintInfo | Gets an object providing information on the NavBarControl’s element for which the hint event was fired. Inherited from NavBarCustomHintEventArgs. |
| Link | Gets the link for which the hint is displayed. Inherited from NavBarCustomHintEventArgs. |
| Size | Gets or sets hint size. |
Write a CalcHintSize event handler to perform hint size corrections before a hint is displayed in the VSToolBoxView paint style. Typically, you need to correct the hint size to perform custom painting via the NavBarControl.CustomDrawHint event.
In other paint styles, the CalcHintSize event is not in effect. To customize the hint size and custom paint hints in these styles, handle the ToolTipController.CalcSize and ToolTipController.CustomDraw events of a tooltip controller object (for instance, of the DefaultToolTipController object).
In the VSToolBoxView paint style, hints are supported only for groups. The event’s parameter allows you to determine the group on which a hint is about to be displayed.
Hint text of groups/links is specified via the NavElement.Hint property. Write a NavBarControl.GetHint event handler to assign custom text and style to a hint before it is displayed. The NavBarControl.CalcHintSize event fires for each element whose hint text is not empty.
The sample code below handles the NavBarControl.CustomDrawHint event to custom paint hints in the VSToolBoxView style. The NavBarControl.CalcHintSize event is handled to adjust the size of the hints in order to draw their outer borders.
The image below shows the result.
using System.Drawing.Drawing2D;
private void navBarControl1_CalcHintSize(object sender, NavBarCalcHintSizeEventArgs e)
{
// Enlarge the size of the hint to create space for drawing borders
Size NewSize = e.Size;
NewSize.Width += 18;
NewSize.Height += 8;
e.Size = new Size(NewSize.Width, NewSize.Height);
}
private void navBarControl1_CustomDrawHint(object sender, NavBarCustomDrawHintEventArgs e)
{
// Obtain the object used to paint.
Graphics gr = e.PaintArgs.Graphics;
// Paint borders.
LinearGradientBrush outerBrush = new LinearGradientBrush(e.Bounds,
Color.LightSkyBlue, Color.Blue, LinearGradientMode.Vertical);
gr.FillRectangle(outerBrush, e.Bounds);
outerBrush.Dispose();
// Paint the background.
// The background rectangle is reduced to make the borders visible.
Rectangle innerRect = Rectangle.Inflate(e.Bounds, -3, -3);
LinearGradientBrush innerBrush = new LinearGradientBrush(e.Bounds,
Color.Blue, Color.LightSkyBlue, LinearGradientMode.Vertical);
gr.FillRectangle(innerBrush, innerRect);
innerBrush.Dispose();
// Format the output string.
RectangleF textRect = new RectangleF(innerRect.Left, innerRect.Top,
innerRect.Width, innerRect.Height);
StringFormat outStringFormat = new StringFormat();
outStringFormat.Alignment = StringAlignment.Center;
outStringFormat.LineAlignment = StringAlignment.Center;
// Paint text.
SolidBrush textBrush = new SolidBrush(Color.White);
gr.DrawString(e.Hint, e.Appearance.Font, textBrush, textRect, outStringFormat);
textBrush.Dispose();
// Prohibit default hint painting
e.Handled = true;
}
Imports DevExpress.XtraNavBar
Imports System.Drawing.Drawing2D
Private Sub NavBarControl1_CalcHintSize(ByVal sender As System.Object, _
ByVal e As NavBarCalcHintSizeEventArgs) Handles NavBarControl1.CalcHintSize
' Enlarge the size of the hint to create space for drawing borders
Dim NewSize As Size = e.Size
NewSize.Width += 18
NewSize.Height += 8
e.Size = New Size(NewSize.Width, NewSize.Height)
End Sub
Private Sub NavBarControl1_CustomDrawHint(ByVal sender As System.Object, _
ByVal e As NavBarCustomDrawHintEventArgs) Handles NavBarControl1.CustomDrawHint
' Obtain the object used to paint.
Dim gr As Graphics = e.PaintArgs.Graphics
' Paint borders.
Dim outerBrush As LinearGradientBrush = New LinearGradientBrush(e.Bounds, _
Color.LightSkyBlue, Color.Blue, LinearGradientMode.Vertical)
gr.FillRectangle(outerBrush, e.Bounds)
outerBrush.Dispose()
' Paint the background.
' The background rectangle is reduced to make the borders visible.
Dim innerRect As Rectangle = Rectangle.Inflate(e.Bounds, -3, -3)
Dim innerBrush As LinearGradientBrush = New LinearGradientBrush(e.Bounds, _
Color.Blue, Color.LightSkyBlue, LinearGradientMode.Vertical)
gr.FillRectangle(innerBrush, innerRect)
innerBrush.Dispose()
' Format the output string.
Dim textRect As RectangleF = New RectangleF(innerRect.Left, innerRect.Top, _
innerRect.Width, innerRect.Height)
Dim outStringFormat As StringFormat = New StringFormat()
outStringFormat.Alignment = StringAlignment.Center
outStringFormat.LineAlignment = StringAlignment.Center
' Paint text.
Dim textBrush As SolidBrush = New SolidBrush(Color.White)
gr.DrawString(e.Hint, e.Appearance.Font, textBrush, textRect, outStringFormat)
textBrush.Dispose()
' Prohibit default hint painting
e.Handled = True
End Sub
See Also