public boolean removeColumn(int i) {
    if (getColumn(i) == null)
      return false;
    this.mColumns.remove(i);
    return true;
  }
public boolean removeColumn ( int i ) { if ( getColumn ( i ) == null ) return false ; this . mColumns . remove ( i ) ; return true ; }
Remove a column by its index

@param i Column index
@return true if succeed