Disable Cell Editors and Nodes

• Feb 19, 2024
• 2 minutes to read

If a cell is disabled, the user cannot edit and select its value.

Disable All Cells

Set the TreeList’s OptionsBehavior.Editable property to false to disable all cells.

C#

treeList1.OptionsBehavior.Editable = false;

VB.NET

treeList1.OptionsBehavior.Editable = False

Disable Cells in a Column

Set a column’s OptionsColumn.AllowEdit property to false to disable its cells.

C#

treeList1.Columns["Region"].OptionsColumn.AllowEdit = false;

VB.NET

treeList1.Columns("Region").OptionsColumn.AllowEdit = False

Enable a column’s OptionsColumn.ReadOnly setting to make its cells read-only (the OptionsColumn.AllowEdit property must be set to true). The user can invoke the cell’s editor to copy its value, but cannot edit that value.

C#

treeList1.OptionsBehavior.Editable = true;
treeList1.Columns["Region"].OptionsColumn.AllowEdit = true;
treeList1.Columns["Region"].OptionsColumn.ReadOnly = true;

VB.NET

treeList1.OptionsBehavior.Editable = True
treeList1.Columns("Region").OptionsColumn.AllowEdit = True
treeList1.Columns("Region").OptionsColumn.ReadOnly = True

Disable Specific Cells and Nodes Based on a Condition

Use one of the following options to disable specific cells or nodes based on a condition:

• Handle the ShowingEditor event and set the e.Cancel parameter to true to disable the processed cell based on a specific condition.

  The following example handles the ShowingEditor event to disable cells in the focused row if the value in the Region column is “Germany”:

  C#

  private void treeList1_ShowingEditor(object sender, CancelEventArgs e) {
      string cellValue = treeList1.GetRowCellValue(treeList1.FocusedNode, "Region").ToString();
      e.Cancel = cellValue == "Germany";
  }
  

  VB.NET

  Private Sub treeList1_ShowingEditor(ByVal sender As Object, ByVal e As CancelEventArgs)
      Dim cellValue As String = treeList1.GetRowCellValue(treeList1.FocusedNode, "Region").ToString()
      e.Cancel = cellValue = "Germany"
  End Sub
  

  The following example prevents users from editing cells in the “Region” column in child nodes (the example makes cells read-only):

  C#

  private void treeList1_ShownEditor(object sender, EventArgs e) {
      treeList1.ActiveEditor.Properties.ReadOnly = treeList1.FocusedColumn.FieldName == "Region" && treeList1.FocusedNode.Level > 0;
  }
  

  VB.NET

  Private Sub treeList1_ShownEditor(ByVal sender As Object, ByVal e As EventArgs)
      treeList1.ActiveEditor.Properties.ReadOnly = treeList1.FocusedColumn.FieldName = "Region" AndAlso treeList1.FocusedNode.Level > 0
  End Sub
  

• Use the Disabled Cell Behavior to disable cells in nodes that meet a specific condition. Disabled cells are grayed-out and cannot be edited.