setColumn method

@override void setColumn(int index)

Sets the active column for subsequent operations.

This method is called before getLength and buildItem to specify which column is being processed. The index is typically 0-based.

Parameters:

• index - The column index to activate

Implementation

@override
void setColumn(int index) {
  if (index != -1 && _col == index + 1) return;
  _col = index + 1;
  if (_col >= data.length) {
    cur = null;
  } else {
    cur = data[_col];
  }
}