Tried to add custom buttons to toolbar.
rightsButton = new RadToolBarButton();rightsButton.ToolTip = CreaSoft.CommonServices.ResourceHelpers.GetGlobalResourceObject("FileExplorerControl.DirectoryRights");rightsButton.Value = "ManageRightsFolder";rightsButton.CommandName = "ManageRightsFolder";Explorer.ToolBar.Items.Add(rightsButton);
Then I found it doesn't work as expected. Seems that icons are missing (ok, I didn't define any, but found now way how to do it), but based on html, it generates tooltip as css class :-)
Then I found some strange code in Telerik_UI_for_ASP.NET_AJAX_2018_3_910_Source\Telerik.Web.UI\FileExplorer\RadFileExplorer.cs.
private void ConfigureToolbarButtons(){ bool isClassicMode = RenderMode == UI.RenderMode.Classic; if (!isClassicMode) { _toolbar.EnableImageSprites = true; } string icn = "icn"; foreach (RadToolBarItem button in _toolbar.Items) { bool hasText = !String.IsNullOrEmpty(button.Text) && button.Text != Nbsp; string iconCssClass = String.Concat(icn, button.ToolTip); if (isClassicMode) { button.CssClass += hasText ? string.Empty : " rtbIconOnly "; button.CssClass += iconCssClass; } else { button.ShowText = hasText ? ToolBarShowPosition.Toolbar : ToolBarShowPosition.OverFlow; button.SpriteCssClass = iconCssClass; } }}
So it seems to be a bug in this method. Css class should not be generated from Tooltip :-)
Please see attachments.

