The R13B03 release.OTP_R13B03

1 files changed, 1939 insertions, 0 deletions

diff --git a/lib/tv/src/tv_pg_gridfcns.erl b/lib/tv/src/tv_pg_gridfcns.erl
new file mode 100644
index 0000000000..809403fd96
--- /dev/null
+++ b/lib/tv/src/tv_pg_gridfcns.erl
@@ -0,0 +1,1939 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 1997-2009. All Rights Reserved.
+%% 
+%% The contents of this file are subject to the Erlang Public License,
+%% Version 1.1, (the "License"); you may not use this file except in
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%% 
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%% 
+%% %CopyrightEnd%
+-module(tv_pg_gridfcns).
+
+
+
+
+-export([init_grid/8, 
+	 resize_grid/3, 
+	 resize_grid_column/4, 
+	 update_grid_data/3,
+	 scroll_grid_horizontally/2, 
+	 mark_cell_and_notify/4, 
+	 remove_marks/1,
+	 mark_col/2, 
+	 mark_row/2,
+	 handle_list_info/2
+	]).
+
+
+
+
+
+-include("tv_pd_int_msg.hrl").
+-include("tv_pg_int_def.hrl").
+
+
+
+
+
+
+
+%%%*********************************************************************
+%%% EXTERNAL FUNCTIONS
+%%%*********************************************************************
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+init_grid(GridParentId, GridWidth, 
+	  GridHeight, GridXpos, GridYpos, NofRows, RowHeight, ProcVars) ->
+
+       % Get the size and ID of the grid-parent frame, i.e., the
+       % grid-frame! Do not confuse the base-frames below with 
+       % the grid-frame!
+
+    #process_variables{parent_pid  = ParentPid,
+		       grid_params = GridP}   = ProcVars,
+    
+    #grid_params{fg_color        = GridFgColor,
+		 nof_cols        = NofCols,
+		 col_width       = DefaultColWidth,
+		 first_col_shown = FirstColShown,
+		 col_widths      = ColWidths} = GridP,
+    
+       % Create the two frames the column frames are placed on!
+       % These two frames defines the size of the grid.
+    BgFrame = create_base_frame(GridParentId, GridWidth, GridHeight, 
+				 GridXpos, GridYpos, GridFgColor),
+    FgFrame = create_base_frame(BgFrame, GridWidth - 1, GridHeight - 1, 
+			    0, 0, GridFgColor),
+
+       % Compute the the colwidths necessary to cover the grid.
+    ColsShown = compute_cols_shown(FirstColShown, ColWidths, GridWidth, NofCols, 
+				   DefaultColWidth),
+    NofRowsShown = compute_rows_shown(GridHeight, RowHeight),
+
+       % Tell parent about the width of columns shown!
+    ParentPid ! #pg_col_info{sender              = self(),
+			     first_col_shown     = FirstColShown,
+			     width_of_cols_shown = ColsShown,
+			     nof_rows_shown      = NofRowsShown
+			    },
+
+    NewNofCols = max(length(ColsShown), NofCols),
+
+       % The GridColWidths list shall contain the current width of each frame.
+    NewColWidths = update_col_widths(ColsShown, ColWidths, FirstColShown, 
+				     DefaultColWidth),
+    
+       % Create column frames, one for each column, and rows (labels) on each frame.
+    {FrameIdList, ColLabelList} = create_col_frames(NewNofCols, NofRows, RowHeight,
+						    FgFrame, GridP, [], []),
+
+       % Get lists of label-ID's for each row. (When we created the column frames,
+       % we got the id's of labels placed on each column, i.e., vertically. 
+       % However, most often we want the id's for one row, i.e., label id's
+       % horisontally.)
+    RowIdList    = get_row_ids(NofRows, ColLabelList, []),
+    
+       % Update the grid_params record with the new values!
+    NewGridP = GridP#grid_params{bg_frame       = BgFrame,
+				 fg_frame       = FgFrame,
+				 grid_width     = GridWidth,
+				 grid_height    = GridHeight,
+				 grid_xpos      = GridXpos,
+				 grid_ypos      = GridYpos,
+				 nof_cols       = NewNofCols,
+				 col_widths     = NewColWidths,
+				 cols_shown     = ColsShown,
+				 nof_rows       = NofRows,
+				 row_height     = RowHeight,
+				 nof_rows_shown = NofRowsShown,
+				 col_frame_ids  = FrameIdList,
+				 col_ids        = ColLabelList,
+				 row_ids        = RowIdList,
+				 row_data_list  = lists:duplicate(NofRows, notext)
+				},
+    
+    ProcVars#process_variables{grid_parent_id = GridParentId, 
+			       grid_params    = NewGridP}.
+
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+resize_grid(NewWidth, NewHeight, ProcVars) ->
+    #process_variables{parent_pid  = ParentPid,
+		       grid_params = GridP,
+		       mark_params  = MarkP}   = ProcVars,
+    
+    #grid_params{bg_frame         = BgFrame,
+		 fg_frame         = FgFrame,
+		 nof_cols         = NofCols,
+		 nof_rows         = NofRows,
+		 col_width        = DefaultColWidth,
+		 first_col_shown  = FirstColShown,
+		 col_widths       = ColWidths,
+		 row_height       = RowHeight,
+		 col_frame_ids    = ColFrameIds,
+		 col_ids          = ColIds,
+		 row_ids          = RowIds,
+		 bg_color         = BgColor,
+		 fg_color         = FgColor,
+		 row_data_list    = RowDataList,
+		 lists_as_strings = ListAsStr}  = GridP,
+    
+    gs:config(BgFrame, [{width, NewWidth},
+			{height, NewHeight}
+		       ]),
+    gs:config(FgFrame, [{width, NewWidth - 1},
+			{height, NewHeight - 1}
+		       ]),
+
+    ColsShown    = compute_cols_shown(FirstColShown, ColWidths, NewWidth, NofCols, 
+				      DefaultColWidth),
+
+    NofRowsShown = compute_rows_shown(NewHeight, RowHeight),
+
+
+       % Tell parent about the width of columns shown!
+    ParentPid ! #pg_col_info{sender              = self(),
+			     first_col_shown     = FirstColShown,
+			     width_of_cols_shown = ColsShown,
+			     nof_rows_shown      = NofRowsShown
+			    },
+
+    NewColWidths = update_col_widths(ColsShown, ColWidths, FirstColShown, 
+				     DefaultColWidth),
+    
+    NofColsShown = length(ColsShown),
+    {NewNofCols, NewColFrameIds, NewColIds, NewRowIds} = 
+	check_nof_cols(ColsShown, (NofColsShown - NofCols), ColFrameIds, ColIds, 
+		       RowIds, NofRows, RowHeight, FgColor, BgColor ),
+
+    clear_fields(lists:nthtail(NofColsShown, NewColIds), 
+		 lists:nthtail(NofRowsShown, NewRowIds)),
+
+    RowsToUpdate = lists:sublist(NewRowIds, NofRowsShown),
+
+    refresh_visible_rows(RowsToUpdate, FirstColShown, NofColsShown, RowDataList, ListAsStr),
+    
+    NewGridP = GridP#grid_params{grid_width     = NewWidth,
+				 grid_height    = NewHeight,
+				 nof_cols       = NewNofCols,
+				 nof_rows_shown = NofRowsShown,
+				 cols_shown     = ColsShown,
+				 col_widths     = NewColWidths,
+				 col_frame_ids  = NewColFrameIds,
+				 col_ids        = NewColIds,
+				 row_ids        = NewRowIds
+				},
+
+    refresh_marks(NewGridP, MarkP),
+
+    ProcVars#process_variables{grid_params = NewGridP}.
+    
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+resize_grid_column(RealCol, VirtualCol, Xdiff, ProcVars) ->
+    #process_variables{parent_pid  = ParentPid,
+		       grid_params = GridP,
+		       mark_params = MarkP}   = ProcVars,
+    
+    #grid_params{grid_width       = GridWidth,
+		 first_col_shown  = FirstColShown,
+		 nof_cols         = NofCols,
+		 col_widths       = ColWidths,
+		 col_frame_ids    = ColFrameIds,
+		 col_ids          = ColIds,
+		 col_width        = DefaultColWidth,
+		 row_ids          = RowIds,
+		 max_col_width    = MaxColWidth,
+		 min_col_width    = MinColWidth,
+		 nof_rows         = NofRows,
+		 nof_rows_shown   = NofRowsShown,
+		 row_height       = RowHeight,
+		 bg_color         = BgColor,
+		 fg_color         = FgColor,
+		 row_data_list    = RowDataList,
+		 lists_as_strings = ListAsStr}  = GridP,
+    
+       % Get new width!
+    Width = min(MaxColWidth, max((lists:nth(VirtualCol, ColWidths) + Xdiff),
+				 MinColWidth)),
+
+       % Resize the column.
+    NewWidthOfCol = resize_one_column(RealCol, Width, ColFrameIds, MaxColWidth, 
+				      MinColWidth),
+
+       % Update the ColWidths list.
+    TempColWidths = lists:sublist(ColWidths, VirtualCol - 1) ++ 
+	[NewWidthOfCol | lists:nthtail(VirtualCol, ColWidths)],
+    
+       % Check the other columns, whether a new column has to be created.
+    ColsShown    = compute_cols_shown(FirstColShown, TempColWidths, GridWidth, 
+				      NofCols, DefaultColWidth),
+
+       % Get the final ColWidths list, after all updates!
+    NewColWidths = update_col_widths(ColsShown, TempColWidths, FirstColShown, 
+				     DefaultColWidth),
+
+       % Tell parent about the width of columns shown!
+    ParentPid ! #pg_col_info{sender              = self(),
+			     first_col_shown     = FirstColShown,
+			     width_of_cols_shown = ColsShown,
+			     nof_rows_shown      = NofRowsShown
+			    },
+
+       % Get the new number of columns (may have changed).
+    NofColsShown = length(ColsShown),
+    {NewNofCols, NewColFrameIds, NewColIds, NewRowIds} = 
+	check_nof_cols(ColsShown, (NofColsShown - NofCols), ColFrameIds, ColIds, 
+		       RowIds, NofRows, RowHeight, FgColor, BgColor ),
+
+    RowsToUpdate = lists:sublist(NewRowIds, NofRowsShown),
+    refresh_visible_rows(RowsToUpdate, FirstColShown, NofColsShown, RowDataList, ListAsStr),
+    
+    NewGridP = GridP#grid_params{nof_cols       = NewNofCols,
+				 cols_shown     = ColsShown,
+				 col_widths     = NewColWidths,
+				 col_frame_ids  = NewColFrameIds,
+				 col_ids        = NewColIds,
+				 row_ids        = NewRowIds
+				},
+
+    refresh_marks(NewGridP, MarkP),
+
+    ProcVars#process_variables{grid_params = NewGridP}.
+    
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+handle_list_info(ListAsStr, ProcVars) ->
+    #process_variables{grid_params = GridP}   = ProcVars,
+    
+    #grid_params{first_col_shown  = FirstColShown,
+		 cols_shown       = ColsShown,
+		 nof_rows_shown   = NofRowsShown,
+		 row_data_list    = RowDataList,
+		 row_ids          = RowIds,
+		 lists_as_strings = OldListAsStr}  = GridP,
+
+    case ListAsStr of
+	OldListAsStr ->
+	    ProcVars;
+	_NewValue ->
+	    NofColsShown = length(ColsShown),
+	    RowsToUpdate = lists:sublist(RowIds, NofRowsShown),
+	    refresh_visible_rows(RowsToUpdate, FirstColShown, NofColsShown, 
+				 RowDataList, ListAsStr),
+	    NewGridP = GridP#grid_params{lists_as_strings = ListAsStr},
+	    ProcVars#process_variables{grid_params = NewGridP}
+    end.
+    
+
+
+
+update_grid_data(Data, FirstRowShown, ProcVars) ->
+    #process_variables{grid_params = GridP,
+		       mark_params = MarkP}   = ProcVars,
+    
+    #grid_params{first_col_shown  = FirstColShown,
+		 cols_shown       = ColsShown,
+		 nof_rows         = NofRows,
+		 nof_rows_shown   = NofRowsShown,
+		 row_ids          = RowIds,
+		 lists_as_strings = ListAsStr}  = GridP,
+    
+    NofColsShown = length(ColsShown),
+    RowsToUpdate = lists:sublist(RowIds, NofRowsShown),
+
+    NewMarkP = move_marks(FirstColShown, FirstRowShown, GridP, MarkP),
+
+    update_visible_rows(RowsToUpdate, FirstColShown, NofColsShown, Data, ListAsStr),
+    NewRowDataList = make_row_data_list(1, NofRows, Data),
+    
+    NewGridP = GridP#grid_params{first_row_shown = FirstRowShown,
+				 row_data_list   = NewRowDataList},
+
+    ProcVars#process_variables{grid_params = NewGridP,
+			       mark_params = NewMarkP}.
+    
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+scroll_grid_horizontally(NewFirstColShown, ProcVars) ->
+    #process_variables{parent_pid  = ParentPid,
+		       grid_params = GridP,
+		       mark_params = MarkP}   = ProcVars,
+    
+    #grid_params{grid_width       = Width,
+		 nof_cols         = NofCols,
+		 nof_rows         = NofRows,
+		 nof_rows_shown   = NofRowsShown,
+		 first_row_shown  = FirstRowShown,
+		 col_width        = DefaultColWidth,
+		 max_col_width    = MaxColWidth,
+		 min_col_width    = MinColWidth,
+		 col_widths       = ColWidths,
+		 row_height       = RowHeight,
+		 col_frame_ids    = ColFrameIds,
+		 col_ids          = ColIds,
+		 row_ids          = RowIds,
+		 bg_color         = BgColor,
+		 fg_color         = FgColor,
+		 row_data_list    = RowDataList,
+		 lists_as_strings = ListAsStr}  = GridP,
+    
+       % Probably it is unnecessary to check whether any new columns shall be 
+       % created or not, but what the heck, we don't want to crash...
+    ColsShown    = compute_cols_shown(NewFirstColShown, ColWidths, Width, NofCols,
+				      DefaultColWidth),
+    NofColsShown = length(ColsShown),
+
+    ParentPid ! #pg_col_info{sender              = self(),
+			     first_col_shown     = NewFirstColShown,
+			     width_of_cols_shown = ColsShown,
+			     nof_rows_shown      = NofRowsShown
+			    },
+
+    NewMarkP = move_marks(NewFirstColShown, FirstRowShown, GridP, MarkP),
+
+    NewColWidths = update_col_widths(ColsShown, ColWidths, NewFirstColShown, 
+				     DefaultColWidth),
+    
+    {NewNofCols, NewColFrameIds, NewColIds, NewRowIds} = 
+	check_nof_cols(ColsShown, (NofColsShown - NofCols), ColFrameIds, ColIds, 
+		       RowIds, NofRows, RowHeight, FgColor, BgColor ),
+    
+
+    RowsToUpdate = lists:sublist(NewRowIds, NofRowsShown),
+    resize_all_grid_columns(1, ColsShown, NewColFrameIds, MaxColWidth, MinColWidth),
+
+    refresh_visible_rows(RowsToUpdate, NewFirstColShown, NofColsShown, RowDataList, ListAsStr),
+
+       % Clear fields currently not visible.
+    clear_fields(lists:nthtail(NofColsShown, NewColIds), 
+		 lists:nthtail(NofRowsShown, NewRowIds)),
+
+    
+    NewGridP = GridP#grid_params{nof_cols        = NewNofCols,
+				 cols_shown      = ColsShown,
+				 col_widths      = NewColWidths,
+				 col_frame_ids   = NewColFrameIds,
+				 col_ids         = NewColIds,
+				 row_ids         = NewRowIds,
+				 first_col_shown = NewFirstColShown
+				},
+
+    ProcVars#process_variables{grid_params = NewGridP,
+			       mark_params = NewMarkP}.
+    
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+mark_row(VirtualRow, ProcVars) ->
+    #process_variables{grid_params = GridP,
+		       mark_params = MarkP} = ProcVars,
+    
+    #grid_params{first_row_shown = FirstRowShown,
+		 nof_rows_shown  = NofRowsShown,
+		 row_ids         = RowIds}  = GridP,
+    
+    mark_row(VirtualRow, FirstRowShown, FirstRowShown + NofRowsShown - 1, RowIds,
+	     ?GRID_MARK_COLOR),
+
+    NewMarkP = MarkP#mark_params{cell_id     = undefined,
+				 virtual_col = undefined,
+				 virtual_row = VirtualRow
+				},
+
+    ProcVars#process_variables{mark_params = NewMarkP}.
+
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+mark_col(VirtualCol, ProcVars) ->
+    #process_variables{grid_params = GridP,
+		       mark_params = MarkP} = ProcVars,
+    
+    #grid_params{first_col_shown = FirstColShown,
+		 cols_shown      = ColsShown,
+		 col_ids         = ColIds}  = GridP,
+    
+    NofColsShown = length(ColsShown),
+    mark_col(VirtualCol, FirstColShown, FirstColShown + NofColsShown - 1, ColIds,
+	     ?GRID_MARK_COLOR),
+
+    NewMarkP = MarkP#mark_params{cell_id     = undefined,
+				 virtual_col = VirtualCol,
+				 virtual_row = undefined
+				},
+
+    ProcVars#process_variables{mark_params = NewMarkP}.
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+mark_cell_and_notify(CellId, RealCol, RealRow, ProcVars) ->
+    #process_variables{parent_pid  = ParentPid,
+		       grid_params = GridP,
+		       mark_params = MarkP} = ProcVars,
+    
+    #grid_params{first_col_shown = FirstColShown,
+		 first_row_shown = FirstRowShown} = GridP,
+
+    OldCellId = MarkP#mark_params.cell_id,
+
+    VirtualCol = FirstColShown + RealCol - 1,
+    VirtualRow = FirstRowShown + RealRow - 1,
+
+    %% Right now, when the table tool only is passive, i.e., we cannot edit
+    %% the table content, we don't want to be able to mark empty cells.
+    
+    {text, CellText} = gs:read(CellId, label),
+
+    CellMarked = case CellText of
+		     "" -> false;
+		     _AnyText when CellId=:=OldCellId -> false;
+		     _AnyText -> true
+		 end,
+
+    remove_marks(ProcVars),
+    update_marked_cells(CellId, OldCellId, CellMarked),
+
+    notify_about_cell_marked(ParentPid, CellMarked, RealCol, RealRow, 
+			     VirtualCol, VirtualRow, CellText),
+    
+    NewMarkP = case CellMarked of
+		   true ->
+		       MarkP#mark_params{cell_id     = CellId,
+					 virtual_col = VirtualCol,
+					 virtual_row = VirtualRow
+					};
+		   false ->
+		       MarkP#mark_params{cell_id     = undefined,
+					 virtual_col = 0,
+					 virtual_row = undefined
+					}
+	       end,
+    
+    ProcVars#process_variables{mark_params = NewMarkP}.
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+remove_marks(ProcVars) ->
+    #process_variables{mark_params = MarkP,
+		       grid_params = GridP} = ProcVars,
+
+    #grid_params{first_col_shown = FirstColShown,
+		 cols_shown      = ColsShown,
+		 col_ids         = ColIds,
+		 first_row_shown = FirstRowShown,
+		 nof_rows_shown  = NofRowsShown,
+		 row_ids         = RowIds}  = GridP,
+
+
+    #mark_params{cell_id     = CellId,
+		 virtual_col = VirtualCol,
+		 virtual_row = VirtualRow} = MarkP,
+
+    case {VirtualCol, VirtualRow} of
+	{undefined, undefined} ->
+	    update_marked_cells(CellId, CellId, false);
+	{_AnyCol, undefined} ->
+	    NofColsShown = length(ColsShown),
+	    unmark_col(VirtualCol, FirstColShown, FirstColShown + NofColsShown - 1, 
+		       ColIds);
+	{undefined, _AnyRow} ->
+	    unmark_row(VirtualRow, FirstRowShown, FirstRowShown + NofRowsShown - 1, 
+		       RowIds);
+	_Other ->
+	    update_marked_cells(CellId, CellId, false)
+    end,
+    
+    NewMarkP = MarkP#mark_params{cell_id     = undefined,
+				 virtual_col = 0,
+				 virtual_row = undefined
+				},
+    ProcVars#process_variables{mark_params = NewMarkP}.
+    
+		 
+
+
+
+
+
+
+
+%%%*********************************************************************
+%%% INTERNAL FUNCTIONS
+%%%*********************************************************************
+
+    
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+move_marks(FirstCol, FirstRow, GridP, MarkP) ->
+    #grid_params{first_col_shown = OldFirstCol,
+		 cols_shown      = ColsShown,
+		 first_row_shown = OldFirstRow,
+		 nof_rows_shown  = NofRowsShown,
+		 col_ids         = ColIds,
+		 row_ids         = RowIds}  = GridP,
+
+    #mark_params{virtual_col = VirtualCol,
+		 virtual_row = VirtualRow} = MarkP,
+
+
+    case {VirtualCol, VirtualRow} of
+	{undefined, undefined} ->
+	    NofColsShown = length(ColsShown),
+	    move_marked_cell(FirstCol, FirstRow, NofColsShown, 
+			     NofRowsShown, RowIds, MarkP);
+	{_AnyCol, undefined} ->
+	    NofColsShown = length(ColsShown),
+	    OldLastCol = OldFirstCol + NofColsShown - 1,
+	    LastCol    = FirstCol + NofColsShown - 1,
+	    move_marked_col(VirtualCol, OldFirstCol, OldLastCol, 
+			    FirstCol, LastCol, ColIds, MarkP);
+	{undefined, _AnyRow} ->
+	    OldLastRow = OldFirstRow + NofRowsShown - 1,
+	    LastRow    = FirstRow + NofRowsShown - 1,
+	    move_marked_row(VirtualRow, OldFirstRow, OldLastRow, 
+			    FirstRow, LastRow, RowIds, MarkP);
+	{_CellCol, _CellRow} ->
+	    NofColsShown = length(ColsShown),
+	    move_marked_cell(FirstCol, FirstRow, NofColsShown, 
+			     NofRowsShown, RowIds, MarkP)
+    end.
+    
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+refresh_marks(GridP, MarkP) ->
+    #grid_params{first_col_shown = FirstCol,
+		 cols_shown      = ColsShown,
+		 first_row_shown = FirstRow,
+		 nof_rows_shown  = NofRowsShown,
+		 col_ids         = ColIds,
+		 row_ids         = RowIds}  = GridP,
+
+    #mark_params{virtual_col = VirtualCol,
+		 virtual_row = VirtualRow} = MarkP,
+
+
+    case {VirtualCol, VirtualRow} of
+	{undefined, undefined} ->
+	    NofColsShown = length(ColsShown),
+	    move_marked_cell(FirstCol, FirstRow, NofColsShown, NofRowsShown, 
+			     RowIds, MarkP);
+	{_AnyCol, undefined} ->
+	    NofColsShown = length(ColsShown),
+	    LastCol    = FirstCol + NofColsShown - 1,
+	    mark_col(VirtualCol, FirstCol, LastCol, ColIds, ?GRID_MARK_COLOR);
+	{undefined, _AnyRow} ->
+	    LastRow    = FirstRow + NofRowsShown - 1,
+	    mark_row(VirtualRow, FirstRow, LastRow, RowIds, ?GRID_MARK_COLOR);
+	{_CellCol, _CellRow} ->
+	    NofColsShown = length(ColsShown),
+	    move_marked_cell(FirstCol, FirstRow, NofColsShown, NofRowsShown, 
+			     RowIds, MarkP)
+    end.
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+move_marked_col(VirtualCol, 
+		OldFirstCol, OldLastCol, FirstCol, LastCol, ColIds, MarkP) ->
+    unmark_col(VirtualCol, OldFirstCol, OldLastCol, ColIds),
+    mark_col(VirtualCol, FirstCol, LastCol, ColIds, ?GRID_MARK_COLOR),
+    MarkP#mark_params{cell_id = undefined}.
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+mark_col(VirtualCol, FirstCol, _LastCol, _ColIds, _Color) when VirtualCol < FirstCol ->
+    done;
+mark_col(VirtualCol, _FirstCol, LastCol, _ColIds, _Color) when VirtualCol > LastCol ->
+    done;
+mark_col(VirtualCol, FirstCol, _LastCol, ColIds, Color) ->
+    RealCol = VirtualCol - FirstCol + 1,
+    MarkedColIds = lists:nth(RealCol, ColIds),
+    mark_all_cells(MarkedColIds, Color).
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+unmark_col(VirtualCol, FirstCol, LastCol, ColIds) ->
+    mark_col(VirtualCol, FirstCol, LastCol, ColIds, ?DEFAULT_GRID_BGCOLOR).
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+mark_all_cells([], _Color) ->
+    done;
+mark_all_cells([CellId | T], Color) ->
+    gs:config(CellId, [{bg, Color}]),
+    mark_all_cells(T, Color).
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+mark_row(VirtualRow, FirstRow, _LastRow, _RowIds, _Color) when VirtualRow < FirstRow ->
+    done;
+mark_row(VirtualRow, _FirstRow, LastRow, _RowIds, _Color) when VirtualRow > LastRow ->
+    done;
+mark_row(VirtualRow, FirstRow, _LastRow, RowIds, Color) ->
+    RealRow      = VirtualRow - FirstRow + 1,
+    MarkedRowIds = lists:nth(RealRow, RowIds),
+    mark_all_cells(MarkedRowIds, Color).
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+unmark_row(VirtualRow, FirstRow, LastRow, RowIds) ->
+    mark_row(VirtualRow, FirstRow, LastRow, RowIds, ?DEFAULT_GRID_BGCOLOR).
+
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+move_marked_row(VirtualRow, 
+		OldFirstRow, OldLastRow, FirstRow, LastRow, RowIds, MarkP) ->
+    unmark_row(VirtualRow, OldFirstRow, OldLastRow, RowIds),
+    mark_row(VirtualRow, FirstRow, LastRow, RowIds, ?GRID_MARK_COLOR),
+    MarkP#mark_params{cell_id = undefined}.
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+move_marked_cell(FirstColShown, 
+		 FirstRowShown, NofColsShown, NofRowsShown, RowIds, MarkP) ->
+    #mark_params{cell_id     = OldCellId,
+		 virtual_col = VirtualCol,
+		 virtual_row = VirtualRow} = MarkP,
+    
+    case OldCellId of
+	undefined ->
+	    MarkP;
+	_OtherId ->
+	    NewRealCol = VirtualCol - FirstColShown + 1,
+	    NewRealRow = VirtualRow - FirstRowShown + 1,
+	    update_marked_cells(undefined, OldCellId, false),
+	    case check_if_new_mark_visible(NewRealCol, NewRealRow, 
+					   NofColsShown, NofRowsShown) of
+		false ->
+		    MarkP;
+		true ->
+		    NewCellId = lists:nth(NewRealCol, 
+					  lists:nth(NewRealRow, RowIds)),
+		    update_marked_cells(NewCellId, undefined, true),
+		    MarkP#mark_params{cell_id  = NewCellId}
+	    end
+    end.
+		    
+					      
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+check_if_new_mark_visible(Col, _Row, NofCols, _NofRows) when Col > NofCols ->
+    false;
+check_if_new_mark_visible(Col, _Row, _NofCols, _NofRows) when Col =< 0 ->
+    false;
+check_if_new_mark_visible(_Col, Row, _NofCols, NofRows) when Row > NofRows ->
+    false;
+check_if_new_mark_visible(_Col, Row, _NofCols, _NofRows) when Row =< 0 ->
+    false;
+check_if_new_mark_visible(_Col, _Row, _NofCols, _NofRows) ->
+    true.
+    
+
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+update_marked_cells(CellId, OldCellId, _MarkedCell) when CellId =:= OldCellId ->
+    gs:config(CellId, [{bg, ?DEFAULT_GRID_BGCOLOR}]);
+update_marked_cells(_CellId, undefined, false) ->
+    done;
+update_marked_cells(CellId, undefined, true) ->
+    gs:config(CellId, [{bg, ?GRID_MARK_COLOR}]);
+update_marked_cells(CellId, OldCellId, true) ->
+    gs:config(OldCellId, [{bg, ?DEFAULT_GRID_BGCOLOR}]),
+    gs:config(CellId, [{bg, ?GRID_MARK_COLOR}]);
+update_marked_cells(_CellId, OldCellId, false) ->
+    gs:config(OldCellId, [{bg, ?DEFAULT_GRID_BGCOLOR}]).
+
+    
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+notify_about_cell_marked(Pid, Marked, RealCol, RealRow, VirtCol, VirtRow, Text) ->
+    Pid ! #pg_cell_marked{sender      = self(),
+			  cell_marked = Marked,
+			  real_col    = RealCol,
+			  real_row    = RealRow,
+			  virtual_col = VirtCol,
+			  virtual_row = VirtRow,
+			  cell_text   = Text
+			 }.
+    
+
+
+
+
+
+
+
+%%%---------------------------------------------------------------------
+%%% START of functions used to print data in the grid fields.
+%%%---------------------------------------------------------------------
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+refresh_visible_rows([], _FirstColShown, _NofColsShown, _DataList, _ListAsStr) ->
+    done;
+refresh_visible_rows(RowIds, _FirstColShown, _NofColsShown, [], _ListAsStr) ->
+    clear_cols_or_rows(RowIds);
+refresh_visible_rows([OneRowIds | RemRowIds], FirstColShown, NofColsShown,
+		    [DataItemList | RemDataItemLists], ListAsStr) ->
+    NewDataItemList = get_data_sublist(DataItemList, FirstColShown, NofColsShown),
+    update_one_row(lists:sublist(OneRowIds, NofColsShown), NewDataItemList, ListAsStr),
+    refresh_visible_rows(RemRowIds, FirstColShown, NofColsShown, RemDataItemLists, ListAsStr).
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+update_visible_rows([], _FirstColShown, _NofColsShown, _DataList, _ListAsStr) ->
+    done;
+update_visible_rows(RowIds, _FirstColShown, _NofColsShown, [], _ListAsStr) ->
+    clear_cols_or_rows(RowIds);
+update_visible_rows([OneRowIds | RemRowIds], FirstColShown, NofColsShown,
+		    [DataItem | RemData], ListAsStr) ->
+       % We convert the received item to a list! This way we know that 
+       % '[notext]' shall be printed as 'notext', while 'notext' shall
+       % be printed as ''.
+    TempDataItemList = item_to_list(DataItem),
+    DataItemList = get_data_sublist(TempDataItemList, FirstColShown, 
+				    NofColsShown),
+    update_one_row(lists:sublist(OneRowIds, NofColsShown), DataItemList, ListAsStr),
+    update_visible_rows(RemRowIds, FirstColShown, NofColsShown, RemData, ListAsStr).
+
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+update_one_row(OneRowIds, [], _ListAsStr) ->
+    clear_one_col_or_row(OneRowIds);
+update_one_row([], _DataItemList, _ListAsStr) ->
+    done;
+update_one_row([LabelId | RemLabelIds], [notext | T], ListAsStr) ->
+    gs:config(LabelId, [{label, {text, ""}}
+		       ]),
+    update_one_row(RemLabelIds, T, ListAsStr);
+update_one_row([LabelId | RemLabelIds], [DataElem | T], ListAsStr) ->
+    Str = case ListAsStr of
+	      true ->
+		  tv_io_lib:format(" ~p", [DataElem]);
+	      false ->
+		  " " ++ lists:flatten(tv_io_lib:write(DataElem))
+	  end,
+    gs:config(LabelId, [{label, {text, Str}}
+		       ]),
+    update_one_row(RemLabelIds, T, ListAsStr).
+    
+		      
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+make_row_data_list(N, NofRows, []) when N > NofRows ->
+    [];
+make_row_data_list(N, NofRows, []) ->
+       % If NofRows == N, we get the empty list here!
+    lists:duplicate(NofRows- N, notext);
+make_row_data_list(N, NofRows, [_DataItem | _RemData]) when N > NofRows ->
+    [];
+make_row_data_list(N, NofRows, [DataItem | RemData]) ->
+       % We convert the received item to a list! This way we know that 
+       % '[notext]' shall be printed as 'notext', while 'notext' shall
+       % be printed as ''.
+    [item_to_list(DataItem) | make_row_data_list(N + 1, NofRows, RemData)].
+    
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+item_to_list(Item) when is_tuple(Item) ->
+    tuple_to_list(Item);
+item_to_list(Item) ->
+    [Item].
+
+    
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+get_data_sublist(DataList, StartPos, Length) ->
+    case catch lists:sublist(DataList, StartPos, Length) of
+	{'EXIT', _Reason} ->
+	    [];
+	Sublist ->
+	    Sublist
+    end.
+
+
+
+
+
+
+
+%%%---------------------------------------------------------------------
+%%% END of functions used to print data in the grid fields.
+%%%---------------------------------------------------------------------
+
+
+
+
+
+%%%---------------------------------------------------------------------
+%%% START of functions used to resize the grid columns.
+%%%---------------------------------------------------------------------
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+resize_all_grid_columns(_RealCol, [], _ColFrameIds, _MaxColWidth, _MinColWidth) ->
+    done;
+resize_all_grid_columns(RealCol, [ColWidth | Tail], ColFrameIds, MaxColWidth, MinColWidth) ->
+
+    resize_one_column(RealCol, ColWidth, ColFrameIds, MaxColWidth, MinColWidth),
+    resize_all_grid_columns(RealCol + 1, Tail, ColFrameIds, MaxColWidth, 
+			    MinColWidth). 
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+resize_one_column(RealCol, Width, ColFrameIds, MaxW, MinW) ->
+    NewWidthOfCol = min(MaxW, max(Width, MinW)),
+    case length(ColFrameIds) of
+	RealCol ->
+	    done;
+	_Other ->
+	    FrameId = lists:nth(RealCol + 1, ColFrameIds), 
+	    gs:config(FrameId, [{x, NewWidthOfCol + 1}])
+    end,
+    NewWidthOfCol.
+
+
+
+
+%%%---------------------------------------------------------------------
+%%% END of functions used to resize the grid columns.
+%%%---------------------------------------------------------------------
+
+
+
+
+
+
+%%%---------------------------------------------------------------------
+%%% START of functions used to update the grid. 
+%%%---------------------------------------------------------------------
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+clear_fields(ColIds, RowIds) ->
+    clear_cols_or_rows(ColIds),
+    clear_cols_or_rows(RowIds).
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+clear_cols_or_rows([]) ->
+    done;
+clear_cols_or_rows([IdList | RemIdLists]) ->
+    clear_one_col_or_row(IdList),
+    clear_cols_or_rows(RemIdLists).
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+clear_one_col_or_row([]) ->
+    done;
+clear_one_col_or_row([LabelId | RemLabelIds]) ->
+    gs:config(LabelId, [{label, {text, ""}}
+		       ]),
+    clear_one_col_or_row(RemLabelIds).
+    
+
+
+
+
+%%%---------------------------------------------------------------------
+%%% END of functions used to update the grid. 
+%%%---------------------------------------------------------------------
+
+
+
+
+
+
+%%%---------------------------------------------------------------------
+%%% START of functions used to compute the part of the grid that has to 
+%%% be updated, as well as deciding whether a new column has to be added.
+%%% Old columns (i.e., columns not visible) are not removed, but they 
+%%% shall not be updated until they once again becomes visible.
+%%%---------------------------------------------------------------------
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+check_nof_cols(_ColsShown, NofNewCols, ColFrameIds, ColIds, RowIds, 
+	       _NofRows, _RowHeight, _FgColor, _BgColor) when NofNewCols =< 0 ->
+    {length(ColFrameIds), ColFrameIds, ColIds, RowIds};
+check_nof_cols(ColsShown, NofNewCols, ColFrameIds, ColIds, 
+	       RowIds, NofRows, RowHeight, FgColor, BgColor) ->
+    NewColNo = length(ColFrameIds) + 1,
+       % We don't care about the pathological case where no columns have been
+       % created. If the gridwidth, or the columnwidth, was set to =< 0 during
+       % initialisation, then no columns will have been created. The program 
+       % will probably also have crashed. If any smart jackass has set invalid
+       % values on these important parameters, then he can only blame himself.
+    ParentId = lists:nth((NewColNo - 1), ColFrameIds),
+    ParentColWidth = lists:nth((NewColNo - 1), ColsShown),
+    Xpos = ParentColWidth + 1,
+
+    {ColFrameId, LabelIds} = add_one_col_frame(ParentId, NewColNo, Xpos, FgColor, 
+					       BgColor, NofRows, RowHeight),
+
+    NewColFrameIds = ColFrameIds ++ [ColFrameId],
+    NewColIds      = ColIds ++ [LabelIds],
+    NewRowIds      = update_row_ids(RowIds, LabelIds),
+    
+    check_nof_cols(ColsShown, NofNewCols - 1, NewColFrameIds, NewColIds, NewRowIds,
+		   NofRows, RowHeight, FgColor, BgColor).
+
+
+    
+    
+    
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+update_row_ids([], _LabelIds) ->
+    [];
+update_row_ids([OneRowIds | RemainingRows], [NewElemId | RemainingElemIds]) ->
+    [OneRowIds ++ [NewElemId] | update_row_ids(RemainingRows, RemainingElemIds)].
+
+
+
+
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+update_col_widths(ColsShown, ColWidths, FirstColShown, DefaultColWidth) ->
+       % What we do here is that we first (if necessary) add default 
+       % column widths to the ColWidth list until it reaches to where 
+       % ColsShown starts (vitually seen). 
+       % In the second step we take the appropriate elements from the
+       % ColsShown list and add them to the ColWidths list, until it is
+       % of sufficient length. 
+       % Of course this may seem unnecessary - it would suffice to just
+       % add default widths to the ColWidths list until it is long enough,
+       % since the compute_cols_shown function  right now just adds default 
+       % width columns to the ColsShown list, when the ColWidths list is empty.
+       % However, this could change (maybe we some other time want the last
+       % column to carry all remaining width, instead of adding new columns).
+       % Besides, we don't like hidden dependencies between functions!!!
+
+    NofColsShown   = length(ColsShown),
+    NewColWidths   = set_necessary_col_widths_length(FirstColShown, ColWidths, 
+						 DefaultColWidth),
+       % Now NofVirtualCols will always be equal to, or greater 
+       % than, FirstColShown - 1.
+    
+    NofVirtualCols          = length(NewColWidths),
+    NecessaryNofVirtualCols = FirstColShown + (NofColsShown - 1),
+    if 
+	NecessaryNofVirtualCols > NofVirtualCols ->
+	    TailNo = NofVirtualCols - FirstColShown + 1,   % Always >= 0 !!!
+	    NewColWidths ++ lists:nthtail(TailNo, ColsShown);
+	true ->
+	    NewColWidths
+    end.
+
+
+
+					  
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+set_necessary_col_widths_length(FirstColShown, ColWidths, DefaultColWidth) ->
+       % First check that (length(ColWidths) - FirstColShown) >= -1.
+       % If not, add elements so the relation holds true!
+    MissingDefaultWidthElems = FirstColShown - length(ColWidths),
+    if 
+	MissingDefaultWidthElems > 1 ->
+	    ColWidths ++ lists:duplicate(MissingDefaultWidthElems - 1, 
+					 DefaultColWidth);
+	true ->
+	    ColWidths
+    end.
+
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+compute_rows_shown(GridHeight, RowHeight) ->
+    (GridHeight div RowHeight) + 1.
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+compute_cols_shown(FirstColShown, ColWidths, GridWidth, _NofCols, DefaultColWidth) ->
+    ColWidthsLength = length(ColWidths),
+       % Normally ColWidths shall be long enough, but just to make sure...
+       % (We could have chosen to update ColWidths here to, but right now
+       % we do it instead explicitly when resizeing the grid, changing the 
+       % column size(s), and scrolling horizontally.)
+    UsedColWidths = if
+			ColWidthsLength < FirstColShown ->
+			    [];
+			true ->
+			    lists:nthtail(FirstColShown - 1, ColWidths)
+		    end,
+    compute_cols_shown(UsedColWidths, GridWidth, DefaultColWidth).
+
+
+
+
+
+
+compute_cols_shown(_ColWidths, RemainingWidth, _DefColW) when RemainingWidth =< 0 ->
+    [];
+compute_cols_shown([], RemainingWidth, DefaultColWidth) ->
+    [DefaultColWidth | compute_cols_shown([], RemainingWidth - DefaultColWidth, 
+					  DefaultColWidth)];
+compute_cols_shown([VirtualColWidth | T], RemainingWidth, DefaultColWidth) ->
+    [VirtualColWidth | compute_cols_shown(T, RemainingWidth - VirtualColWidth,
+					 DefaultColWidth)].
+
+
+    
+    
+
+%%%---------------------------------------------------------------------
+%%% END of functions used to compute the part of the grid that has to 
+%%% be updated, as well as deciding whether a new column has to be added.
+%%%---------------------------------------------------------------------
+
+
+
+
+
+
+
+%%%---------------------------------------------------------------------
+%%% START of functions used to create the grid (baseframes, columns 
+%%% and rows), as well as sorting the ID's appropriately.
+%%%---------------------------------------------------------------------
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+create_base_frame(ParentId, Width, Height, Xpos, Ypos, BgColor) ->
+    gs:frame(ParentId, [{width, Width},
+			{height, Height},
+			{x, Xpos},
+			{y, Ypos},
+			{bg, BgColor}
+		       ]).
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+create_col_frames(0, _NofRows, _RowHeight, _ParentId, _GridP, ColFrameAcc, LabelAcc) ->
+    {lists:reverse(ColFrameAcc), lists:reverse(LabelAcc)};
+create_col_frames(N, NofRows, RowHeight, ParentId, GridP, ColFrameAcc, LabelAcc) ->
+       % Yes, it *IS* inefficient to copy GridP for each loop.
+       % However, it is only done once, and for a limited number of times,
+       % and we avoid having a lot of parameters!
+    #grid_params{bg_color   = BgColor,
+		 fg_color   = FgColor,
+		 nof_cols   = NofCols,
+		 col_width  = ColWidth} = GridP,
+    Xpos = if
+	       N =:= NofCols ->
+		   0;
+	       true ->
+		   ColWidth + 1
+	   end,
+    
+    ColNo = NofCols - N + 1,
+    {ColFrameId, LabelIds} = add_one_col_frame(ParentId, ColNo, Xpos, FgColor, 
+					       BgColor, NofRows, RowHeight),
+    create_col_frames(N - 1, NofRows, RowHeight, ColFrameId, GridP, 
+		      [ColFrameId | ColFrameAcc], [LabelIds | LabelAcc]).
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+add_one_col_frame(ParentId, ColNo, Xpos, FgColor, BgColor, NofRows, RowHeight) ->
+    ColFrameId   = create_one_col_frame(ParentId, Xpos, FgColor),
+    FirstRowYpos = 1, 
+    FirstRowNo   = 1,
+    LabelIds     = create_rows_on_frame(ColFrameId, FirstRowNo, NofRows, RowHeight,
+					FirstRowYpos, FgColor, BgColor, ColNo, []), 
+    {ColFrameId, LabelIds}.
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+create_one_col_frame(ParentId, Xpos, BgColor) ->
+    ColFrameWidth     = 1200,
+    ColFrameHeight    = 900,
+    Ypos = 0,
+    gs:frame(ParentId, [{width, ColFrameWidth},
+			{height, ColFrameHeight},
+			{x, Xpos},
+			{y, Ypos},
+			{bg, BgColor}
+		       ]).
+    
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+create_rows_on_frame(_FrameId, RowNo, NofRows, _H, _Y, _Fg, _Bg, _ColNo, Acc) when RowNo > NofRows -> 
+    lists:reverse(Acc);
+create_rows_on_frame(FrameId, RowNo, NofRows, H, Y, Fg, Bg, ColNo, RAcc) -> 
+    Width = 1200, 
+    R = gs:label(FrameId, [{width, Width},
+			   {height, H},
+			   {x, 1},
+			   {y, Y},
+			   {bg, Bg},
+			   {fg, Fg},
+			   {align, w},
+			   {buttonpress, true},
+			   {data, {gridcell, ColNo, RowNo, FrameId}}
+			  ]),
+    NextRowNo = RowNo + 1,
+    NextY = Y + H +1,
+    create_rows_on_frame(FrameId, NextRowNo, NofRows, H, NextY, Fg, Bg, ColNo, 
+			     [R | RAcc]).
+
+
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+get_row_ids(0, _Cols, RowAcc) ->
+    RowAcc;
+get_row_ids(RowNo, Cols, RowAcc) ->
+    Row = extract_ids_for_one_row(RowNo, Cols),
+    get_row_ids(RowNo - 1, Cols, [Row | RowAcc]).
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+extract_ids_for_one_row(_N, []) ->
+    [];
+extract_ids_for_one_row(N, [ColIds | Tail]) ->
+    [lists:nth(N, ColIds) | extract_ids_for_one_row(N, Tail)].
+
+
+
+%%%---------------------------------------------------------------------
+%%% END of functions used to create the grid.
+%%%---------------------------------------------------------------------
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+max(A, B) when A > B ->
+    A;
+max(_, B) ->
+    B.
+
+
+
+
+
+
+
+%%======================================================================
+%% Function:      
+%%
+%% Return Value:  
+%%
+%% Description:   
+%%
+%% Parameters:    
+%%======================================================================
+
+
+min(A, B) when A < B ->
+    A;
+min(_, B) ->
+    B.
+