This method resizes the row header area so that the row headers and row header graphics can be completely displayed without being truncated or clipped. The RowHeaders.OptimalWidth method can be used to calculate the row header area's optimal width without resizing the row header area. The row header width can be changed using the RowHeaders.Width property.
By changing tree control properties, the optimal row header width may change. Adding items, setting new row header graphics and changing row header text are a few of the actions that can affect the optimal row header width. The row header width may have to be set again to allow items to be completely visible. The tree control does not automatically adjust the row header width.
Calculating the optimal row header width can be a time consuming operation, particularly if many items have been added to the tree control. RowHeaders.OptimalWidth scans all items to determine the best row header width, but can be limited to a specific number of items using the Items.CalcLimit property. This reduces the time spent to calculate the optimal width, but may still leave some items clipped.