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Determining Which Column the User Clicked

Background

There are times when a program needs to identify the Column associated with a mouse click. WinGrid™ provides this capability through the use of the .DisplayLayout.UIElement.ElementFromPoint method and the .GetContext method of the UIElement.

Questions

How do I determine which column the user clicked on?

Solutions

Use the .DisplayLayout.UIElement.ElementFromPoint method to find the UIElement of the mouse click and extract a reference to the Column object with the UIElement .GetContext method.

Sample Project

This sample project illustrates how to determine which column a user clicked on. When this project is run, the user can click on the cells and the column Key value displays in the text box.

Before you start writing any code, you should place using/imports directives in your code-behind so you don’t need to always type out a member’s fully qualified name.

In Visual Basic:

Imports Infragistics.Win
Imports Infragistics.Win.UltraWinGrid

In C#:

using Infragistics.Win;
using Infragistics.Win.UltraWinGrid;
determining which column the user clicked in ultragrid

The UltraWinGrid Events Region contains the following event handlers:

  • UltraGrid1.InitializeLayout - The code in the InitializeLayout event tells the grid to AutoFitStyle:

In Visual Basic:

Private Sub UltraGrid1_InitializeLayout(ByVal sender As Object, _
  ByVal e As Infragistics.Win.UltraWinGrid.InitializeLayoutEventArgs) _
  Handles UltraGrid1.InitializeLayout
	e.Layout.AutoFitStyle = AutoFitStyle.ResizeAllColumns
End Sub

In C#:

private void ultraGrid1_InitializeLayout(object sender,
  Infragistics.Win.UltraWinGrid.InitializeLayoutEventArgs e)
{
	e.Layout.AutoFitStyle = AutoFitStyle.ResizeAllColumns;
}

  • UltraGrid1.MouseUp - The code in the MouseUp event finds the UIElement from the X and Y coordinates of the event, extracts a reference to the Column with the GetContext method, and if a valid Column object reference exists it displays the Column.Key property value in the text box:

In Visual Basic:

Private Sub UltraGrid1_MouseUp(ByVal sender As Object, _
  ByVal e As System.Windows.Forms.MouseEventArgs) _
  Handles UltraGrid1.MouseUp
	' Retrieve the UIElement from the location of the MouseUp
	Dim mouseupUIElement As UIElement = _
	  Me.UltraGrid1.DisplayLayout.UIElement.ElementFromPoint(New Point(e.X, e.Y))
	' Retrieve the Column from the UIElement
	Dim mouseupColumn As UltraGridColumn = mouseupUIElement.GetContext(GetType(UltraGridColumn))
	' If there is a column object reference, display column key
	If Not mouseupColumn Is Nothing Then
		Me.UltraTextEditor1.Text += mouseupColumn.Key + vbCrLf
	End If
End Sub

In C#:

private void ultraGrid1_MouseUp(object sender,
  MouseEventArgs e)
{
	// Retrieve the UIElement from the location of the MouseUp
	UIElement mouseupUIElement =
	  this.ultraGrid1.DisplayLayout.UIElement.ElementFromPoint(new Point(e.X, e.Y));
	// Retrieve the Column from the UIElement
	UltraGridColumn mouseupColumn =
	  (UltraGridColumn)mouseupUIElement.GetContext(typeof(UltraGridColumn));
	// If there is a column object reference, display column key
	if(mouseupColumn != null)
		this.ultraTextEditor1.Text += mouseupColumn.Key + "\n";
}

Review

This project illustrates how to retrieve a Column object reference from the X and Y coordinates of a Mouse event.