From dcbbb0c0a13af29692b1d0c62eeb6fb6daccf64e Mon Sep 17 00:00:00 2001
From: wp_xxyyzz <wp_xxyyzz@8e941d3f-bd1b-0410-a28a-d453659cc2b4>
Date: Wed, 24 Sep 2014 13:59:51 +0000
Subject: [PATCH] fpspreadsheet: Cells for which the OnWriteCellData event
 handler returns null are skipped in virtual mode if they don't carry a
 format.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@3603 8e941d3f-bd1b-0410-a28a-d453659cc2b4
---
 .../examples/other/demo_virtualmode_write.lpr |  3 +++
 components/fpspreadsheet/xlscommon.pas        | 27 ++++++++++++-------
 components/fpspreadsheet/xlsxooxml.pas        | 20 +++++++++-----
 3 files changed, 34 insertions(+), 16 deletions(-)

diff --git a/components/fpspreadsheet/examples/other/demo_virtualmode_write.lpr b/components/fpspreadsheet/examples/other/demo_virtualmode_write.lpr
index ca5e30d1e..3608f0606 100644
--- a/components/fpspreadsheet/examples/other/demo_virtualmode_write.lpr
+++ b/components/fpspreadsheet/examples/other/demo_virtualmode_write.lpr
@@ -44,6 +44,9 @@ var
       // formatting of all virtual cells in row 0.
       // Important: The template cell must be an existing cell in the worksheet.
     end else
+    if (ACol = 0) then
+      AData := NULL     // Let's skip the column #0
+    else
     if odd(random(10)) then begin
       AData := Format('R=%d-C=%d', [ARow, ACol]);
     end else
diff --git a/components/fpspreadsheet/xlscommon.pas b/components/fpspreadsheet/xlscommon.pas
index 3c4db063e..9c89b005f 100644
--- a/components/fpspreadsheet/xlscommon.pas
+++ b/components/fpspreadsheet/xlscommon.pas
@@ -2869,10 +2869,10 @@ var
   lCell: TCell;
   value: variant;
   styleCell: PCell;
-
 begin
-  for r := 0 to Workbook.VirtualRowCount-1 do begin
-    for c := 0 to Workbook.VirtualColCount-1 do begin
+  for r := 0 to Workbook.VirtualRowCount-1 do
+    for c := 0 to Workbook.VirtualColCount-1 do
+    begin
       InitCell(lCell);
       value := varNull;
       styleCell := nil;
@@ -2881,21 +2881,29 @@ begin
       lCell.Row := r;
       lCell.Col := c;
       if VarIsNull(value) then
-        lCell.ContentType := cctEmpty
-      else
-      if VarIsNumeric(value) then begin
+      begin         // ignore empty cells that don't have a format
+        if styleCell <> nil then
+          lCell.ContentType := cctEmpty
+        else
+          Continue;
+      end else
+      if VarIsNumeric(value) then
+      begin
         lCell.ContentType := cctNumber;
         lCell.NumberValue := value;
       end else
-      if VarType(value) = varDate then begin
+      if VarType(value) = varDate then
+      begin
         lCell.ContentType := cctDateTime;
         lCell.DateTimeValue := StrToDateTime(VarToStr(value), Workbook.FormatSettings);
       end else
-      if VarIsStr(value) then begin
+      if VarIsStr(value) then
+      begin
         lCell.ContentType := cctUTF8String;
         lCell.UTF8StringValue := VarToStrDef(value, '');
       end else
-      if VarIsBool(value) then begin
+      if VarIsBool(value) then
+      begin
         lCell.ContentType := cctBool;
         lCell.BoolValue := value <> 0;
       end else
@@ -2903,7 +2911,6 @@ begin
       WriteCellCallback(@lCell, AStream);
       value := varNULL;
     end;
-  end;
 end;
 
 { Writes an Excel 5/8 WINDOW1 record
diff --git a/components/fpspreadsheet/xlsxooxml.pas b/components/fpspreadsheet/xlsxooxml.pas
index 772e2be41..90f3a7485 100755
--- a/components/fpspreadsheet/xlsxooxml.pas
+++ b/components/fpspreadsheet/xlsxooxml.pas
@@ -2010,21 +2010,29 @@ begin
         lCell.Row := r;
         lCell.Col := c;
         if VarIsNull(value) then
-          lCell.ContentType := cctEmpty
-        else
-        if VarIsNumeric(value) then begin
+        begin
+          if styleCell <> nil then
+            lCell.ContentType := cctEmpty
+          else
+            Continue;
+        end else
+        if VarIsNumeric(value) then
+        begin
           lCell.ContentType := cctNumber;
           lCell.NumberValue := value;
         end else
-        if VarType(value) = varDate then begin
+        if VarType(value) = varDate then
+        begin
           lCell.ContentType := cctDateTime;
           lCell.DateTimeValue := StrToDate(VarToStr(value), Workbook.FormatSettings);
         end else
-        if VarIsStr(value) then begin
+        if VarIsStr(value) then
+        begin
           lCell.ContentType := cctUTF8String;
           lCell.UTF8StringValue := VarToStrDef(value, '');
         end else
-        if VarIsBool(value) then begin
+        if VarIsBool(value) then
+        begin
           lCell.ContentType := cctBool;
           lCell.BoolValue := value <> 0;
         end;