Working with Trees > Classes > TreeList > TreeList.ColumnVisibilityChanging
ColumnVisibilityChanging: function (sender, args);
sender. Event source.
args. Event information. Available arguments: Column - index of the column, which visibility was changed; Visibility - column visibility: true - column is displayed, false - column is hidden; Cancel- indicates whether checkbox is selected/deselected to change column visibility: true - operation is canceled, false (default value) - operation is not canceled.
The ColumnVisibilityChanging event occurs on changing visibility of a tree column.
Layout of column headings is available if the TreeList.CaptionVisible property is set to true.
To display or hide tree column, click the 
button in the top right corner and in the drop-down menu select or deselect checkboxes for columns to display or hide.
The example of use is given in the TreeList.ColumnVisibilityChanged event description.
See also:
