handle the cell without r attribute in a row element

rows.go

@@ -593,6 +593,22 @@ func checkRow(xlsx *xlsxWorksheet) error {
 		if colCount == 0 {
 			continue
 		}
+		// check and fill the cell without r attribute in a row element
+		rCount := 0
+		for idx, cell := range rowData.C {
+			rCount++
+			if cell.R != "" {
+				lastR, _, err := CellNameToCoordinates(cell.R)
+				if err != nil {
+					return err
+				}
+				if lastR > rCount {
+					rCount = lastR
+				}
+				continue
+			}
+			rowData.C[idx].R, _ = CoordinatesToCellName(rCount, rowIdx+1)
+		}
 		lastCol, _, err := CellNameToCoordinates(rowData.C[colCount-1].R)
 		if err != nil {
 			return err

rows_test.go

@@ -831,6 +831,17 @@ func TestErrSheetNotExistError(t *testing.T) {
 	assert.EqualValues(t, err.Error(), "sheet Sheet1 is not exist")
 }
 
+func TestCheckRow(t *testing.T) {
+	f := NewFile()
+	f.XLSX["xl/worksheets/sheet1.xml"] = []byte(`<?xml version="1.0" encoding="UTF-8" standalone="yes"?><worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" ><sheetData><row r="2"><c><v>1</v></c><c r="F2"><v>2</v></c><c><v>3</v></c><c><v>4</v></c><c r="M2"><v>5</v></c></row></sheetData></worksheet>`)
+	_, err := f.GetRows("Sheet1")
+	assert.NoError(t, err)
+	assert.NoError(t, f.SetCellValue("Sheet1", "A1", false))
+	f = NewFile()
+	f.XLSX["xl/worksheets/sheet1.xml"] = []byte(`<?xml version="1.0" encoding="UTF-8" standalone="yes"?><worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" ><sheetData><row r="2"><c><v>1</v></c><c r="-"><v>2</v></c><c><v>3</v></c><c><v>4</v></c><c r="M2"><v>5</v></c></row></sheetData></worksheet>`)
+	assert.EqualError(t, f.SetCellValue("Sheet1", "A1", false), `cannot convert cell "-" to coordinates: invalid cell name "-"`)
+}
+
 func BenchmarkRows(b *testing.B) {
 	f, _ := OpenFile(filepath.Join("test", "Book1.xlsx"))
 	for i := 0; i < b.N; i++ {

sheet.go

@@ -237,7 +237,7 @@ func (f *File) SetActiveSheet(index int) {
 	for idx, name := range f.GetSheetList() {
 		xlsx, err := f.workSheetReader(name)
 		if err != nil {
-			// Chartsheet
+			// Chartsheet or dialogsheet
 			return
 		}
 		if xlsx.SheetViews == nil {
@@ -365,8 +365,8 @@ func (f *File) GetSheetIndex(name string) int {
 	return idx
 }
 
-// GetSheetMap provides a function to get worksheet and chartsheet name and
+// GetSheetMap provides a function to get worksheet, chartsheet and
-// ID map of XLSX. For example:
+// dialogsheet ID and name map of XLSX. For example:
 //
 //    f, err := excelize.OpenFile("Book1.xlsx")
 //    if err != nil {
@@ -387,8 +387,8 @@ func (f *File) GetSheetMap() map[int]string {
 	return sheetMap
 }
 
-// GetSheetList provides a function to get worksheet and chartsheet name list
+// GetSheetList provides a function to get worksheet, chartsheet and
-// of workbook.
+// dialogsheet name list of workbook.
 func (f *File) GetSheetList() (list []string) {
 	wb := f.workbookReader()
 	if wb != nil {

xmlDrawing.go

@@ -23,6 +23,7 @@ const (
 	SourceRelationshipHyperLink                  = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink"
 	SourceRelationshipWorkSheet                  = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/worksheet"
 	SourceRelationshipChartsheet                 = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/chartsheet"
+	SourceRelationshipDialogsheet                = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/dialogsheet"
 	SourceRelationshipPivotTable                 = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotTable"
 	SourceRelationshipPivotCache                 = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotCacheDefinition"
 	SourceRelationshipSharedStrings              = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/sharedStrings"