/// <summary>
/// Adds an existing ColumnHeader to the collection.
/// </summary>
/// <param name="column">The ColumnHeader to
/// add to the collection. </param>
/// <returns>The zero-based index into the collection
/// where the item was added.</returns>
public int Add(ColumnHeaderEx column)
{
// Add the column to the base
int retValue = base.Add (column);
// Keep a refrence in columnList
columnList.Add(column.ColumnID, column);
// Add the its menu to main menu
ContextMenu.MenuItems.Add(column.ColumnMenuItem);
// Subscribe to the visiblity change event of the column
column.VisibleChanged += new EventHandler(ColumnVisibleChanged);
return retValue;
}
/// <summary>
/// This method is used to find the first visible column
/// which is present in front of the column specified
/// </summary>
/// <param name="column">refrence columns for search</param>
/// <returns>null if no visible colums are in front of
/// the column specified, else previous columns returned</returns>
private ColumnHeaderEx FindPreviousVisibleColumn(ColumnHeaderEx column)
{
// Get the position of the search column
int index = columnList.IndexOfKey(column.ColumnID);
if(index > 0) {
// Start a recursive search for a visible column
ColumnHeaderEx prevColumn = (ColumnHeaderEx)columnList.GetByIndex(index - 1);
if((prevColumn != null) && (prevColumn.Visible == false)) {
prevColumn = FindPreviousVisibleColumn(prevColumn);
}
return prevColumn;
}
// No visible columns found in font of specified column
return null;
}
/// <summary>
/// Method adds a single column header to the collection.
/// </summary>
/// <param name="str">Text to display</param>
/// <param name="width">Width of column</param>
/// <param name="textAlign">Alignment</param>
/// <returns>new ColumnHeaderEx added</returns>
public override ColumnHeader Add(string str, int width, HorizontalAlignment textAlign)
{
ColumnHeaderEx column = new ColumnHeaderEx(str, width, textAlign);
this.Add (column);
return column;
}
