Adding a picture to excel sheet doesn't work in the slightest and hasn't across last 2 (major) versions at least.

[sidetraxaudio]

Bug description

final image = File(p.join(Directory.current.path, 'map.png')).readAsBytesSync();
sheet.pictures.addStream(15, 1, image)

^Results in late initialization exception on lastColOffset.

final image = File(p.join(Directory.current.path, 'map.png')).readAsBytesSync();
sheet.pictures.addStream(15, 1, image)..lastColOffset = 0..lastRowOffset = 0;
final fileName = _createFilename(taEntry);
final bytes = newExcel.saveAsStream();
final File saveFile = File(p.join(exportDirectory.path, fileName));
saveFile.writeAsBytesSync(bytes);

^Results in a corrupted excel file with seemingly incorrect or malformed drawing1.xml and excel reporting:
"We found a problem with some content in [file] Do you want us to recover?"
-> Click Yes and reports:
"Repaired Records: Drawing from /xl/drawings/drawing1.xml part (Drawing shape)"
Result:
Image is located in media folder fine but is not present within the sheet and drawing xml seems to be malformed or incorrect.

Steps to reproduce

As above

Code sample

Code sample

AS ABOVE

Screenshots or Video

Screenshots / Video demonstration

[Upload media here]

Stack Traces

Stack Traces

[ERROR:flutter/runtime/dart_vm_initializer.cc(40)] Unhandled Exception: LateInitializationError: Field 'lastColOffset' has not been initialized.
#0      Picture.lastColOffset (package:syncfusion_flutter_xlsio/src/xlsio/images/picture.dart)
#1      SerializeWorkbook._saveDrawings.<anonymous closure>.<anonymous closure>.<anonymous closure> (package:syncfusion_flutter_xlsio/src/xlsio/general/serialize_workbook.dart:1851:33)
serialize_workbook.dart:1851
#2      XmlBuilder._insert (package:xml/src/xml/builder.dart:326:12)
builder.dart:326
#3      XmlBuilder.element (package:xml/src/xml/builder.dart:178:9)
builder.dart:178
#4      SerializeWorkbook._saveDrawings.<anonymous closure>.<anonymous closure> (package:syncfusion_flutter_xlsio/src/xlsio/general/serialize_workbook.dart:1848:21)
serialize_workbook.dart:1848
#5      XmlBuilder._insert (package:xml/src/xml/builder.dart:326:12)
builder.dart:326
#6      XmlBuilder.element (package:xml/src/xml/builder.dart:178:9)
builder.dart:178
#7      SerializeWorkbook._saveDrawings.<anonymous closure> (package:syncfusion_flutter_xlsio/src/xlsio/general/serialize_workbook.dart:1839:19)
serialize_workbook.dart:1839
#8      XmlBuilder._insert (package:xml/src/xml/builder.dart:326:12)
builder.dart:326
#9      XmlBuilder.element (package:xml/src/xml/builder.dart:178:9)
builder.dart:178
#10     SerializeWorkbook._saveDrawings (package:syncfusion_flutter_xlsio/src/xlsio/general/serialize_workbook.dart:1809:13)
serialize_workbook.dart:1809
#11     SerializeWorkbook._saveWorksheet.<anonymous closure> (package:syncfusion_flutter_xlsio/src/xlsio/general/serialize_workbook.dart:714:9)
serialize_workbook.dart:714
#12     XmlBuilder._insert (package:xml/src/xml/builder.dart:326:12)
builder.dart:326
#13     XmlBuilder.element (package:xml/src/xml/builder.dart:178:9)
builder.dart:178
#14     SerializeWorkbook._saveWorksheet (package:syncfusion_flutter_xlsio/src/xlsio/general/serialize_workbook.dart:453:13)
serialize_workbook.dart:453
#15     SerializeWorkbook._saveWorksheets (package:syncfusion_flutter_xlsio/src/xlsio/general/serialize_workbook.dart:390:7)
serialize_workbook.dart:390
#16     SerializeWorkbook.saveInternal (package:syncfusion_flutter_xlsio/src/xlsio/general/serialize_workbook.dart:110:5)
serialize_workbook.dart:110
#17     Workbook.saveAsStream (package:syncfusion_flutter_xlsio/src/xlsio/general/workbook.dart:6221:16)
</details>


### On which target platforms have you observed this bug?

Windows

### Flutter Doctor output

<details open><summary>Doctor output</summary>

```console
flutter doctor -v
[√] Flutter (Channel beta, 3.27.0-0.2.pre, on Microsoft Windows [Version 10.0.26100.2454], locale en-AU)
    • Flutter version 3.27.0-0.2.pre on channel beta at C:\flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision fc011960a2 (2 weeks ago), 2024-11-14 12:19:18 -0800
    • Engine revision 397deba30f
    • Dart version 3.6.0 (build 3.6.0-334.4.beta)
    • DevTools version 2.40.1

[√] Windows Version (Installed version of Windows is version 10 or higher)

[√] Android toolchain - develop for Android devices (Android SDK version 34.0.0)
    • Android SDK at *
    • Platform android-34, build-tools 34.0.0
    • Java binary at: C:\Program Files\Android\Android Studio2\jbr\bin\java
    • Java version OpenJDK Runtime Environment (build 21.0.3+-12282718-b509.11)
    • All Android licenses accepted.

[√] Chrome - develop for the web
    • Chrome at C:\Program Files\Google\Chrome\Application\chrome.exe

[√] Visual Studio - develop Windows apps (Visual Studio Professional 2022 17.10.8)
    • Visual Studio at C:\Program Files\Microsoft Visual Studio\2022\Professional
    • Visual Studio Professional 2022 version 17.10.35326.205
    • Windows 10 SDK version 10.0.22621.0

[!] Android Studio (version 2023.3)
    • Android Studio at C:\Program Files\Android\Android Studio
    • Flutter plugin can be installed from:
       https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
       https://plugins.jetbrains.com/plugin/6351-dart
    X Unable to determine bundled Java version.
    • Try updating or re-installing Android Studio.

[!] Android Studio (version 2024.1)
    • Android Studio at C:\Program Files\Android\Android Studio1
    • Flutter plugin can be installed from:
       https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
       https://plugins.jetbrains.com/plugin/6351-dart
    X Unable to determine bundled Java version.
    • Try updating or re-installing Android Studio.

[√] Android Studio (version 2024.2)
    • Android Studio at C:\Program Files\Android\Android Studio2
    • Flutter plugin can be installed from:
       https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
       https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 21.0.3+-12282718-b509.11)

[√] VS Code (version 1.95.3)
    • VS Code at *
    • Flutter extension version 3.101.20241031

[√] Connected device (3 available)
    • Windows (desktop) • windows • windows-x64    • Microsoft Windows [Version 10.0.26100.2454]
    • Chrome (web)      • chrome  • web-javascript • Google Chrome 131.0.6778.86
    • Edge (web)        • edge    • web-javascript • Microsoft Edge 131.0.2903.70

[√] Network resources
    • All expected network resources are available.

! Doctor found issues in 2 categories.

[PandikumarSF2691]

Hi @sidetraxaudio ,

We have created a sample using Syncfusion Flutter XlsIO to generate an Excel file and add an image, and the results come out as expected. Please review it and let us know if you are still encountering the issue.

Code snippet:
// Create a new Excel workbook
final Workbook workbook = Workbook();
final Worksheet sheet = workbook.worksheets[0];

// Load image from assets
final ByteData imageData = await rootBundle.load('logo.png');
final List imageBytes = imageData.buffer.asUint8List();

// Add the image to the worksheet at cell A1
sheet.pictures.addStream(1, 2, imageBytes);

// Save workbook to bytes
final List bytes = workbook.saveAsStream();
workbook.dispose();

// Save and launch the file
await saveAndLaunchFile(bytes, 'ExcelWithImage.xlsx');

Regards,
Pandi kumar D.