/// <summary>
/// Adds some columnsItem to the aggregation {@link #getColumnsItems columnsItems}.
/// </summary>
/// <param name="oColumnsItem">The columnsItem to add; if empty, nothing is inserted</param>
/// <returns>Reference to <code>this</code> in order to allow method chaining</returns>
public extern virtual sap.m.P13nColumnsPanel addColumnsItem(sap.m.P13nColumnsItem oColumnsItem);
/// <summary>
/// Checks for the provided <code>sap.m.P13nColumnsItem</code> in the aggregation {@link #getColumnsItems columnsItems}. and returns its index if found or -1 otherwise.
/// </summary>
/// <param name="oColumnsItem">The columnsItem whose index is looked for</param>
/// <returns>The index of the provided control in the aggregation if found, or -1 otherwise</returns>
public extern virtual int indexOfColumnsItem(sap.m.P13nColumnsItem oColumnsItem);
/// <summary>
/// Inserts a columnsItem into the aggregation {@link #getColumnsItems columnsItems}.
/// </summary>
/// <param name="oColumnsItem">The columnsItem to insert; if empty, nothing is inserted</param>
/// <param name="iIndex">The <code>0</code>-based index the columnsItem should be inserted at; for a negative value of <code>iIndex</code>, the columnsItem is inserted at position 0; for a value greater than the current size of the aggregation, the columnsItem is inserted at the last position</param>
/// <returns>Reference to <code>this</code> in order to allow method chaining</returns>
public extern virtual sap.m.P13nColumnsPanel insertColumnsItem(sap.m.P13nColumnsItem oColumnsItem, int iIndex);