saveFile() incomplete documentation

[timoxd7]

Describe the bug
On iOS, the saveFile method returns a String. The file then needs to be saved to the path described by this string. The "bytes" parameter has no effect.
On Android however, the Data is given by the "bytes" parameter and this given data is saved instead.

Platform

• Android
• iOS
• Web
• Desktop

Platform OS version
iOS 17.5
Android ?

How are you picking?

outputFile = await FilePicker.platform.saveFile(
  dialogTitle: 'Please select an output file:',
  fileName: 'log.txt',
  type: FileType.any,
  bytes: currentLogBytes,
);

if (Platform.isIOS) File(outputFile).write(currentLogBytes);

Details to reproduce the issue
Use Code above.

Flutter Version details
[✓] Flutter (Channel stable, 3.22.1, on macOS 14.5 23F79 darwin-arm64, locale de-DE)
• Flutter version 3.22.1 on channel stable at /Users/timo/sdk/flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision a14f74ff3a (13 days ago), 2024-05-22 11:08:21 -0500
• Engine revision 55eae6864b
• Dart version 3.4.1
• DevTools version 2.34.3

Additional context
file_picker 8.0.3

[navaronbracke]

I think this issue points to a bit of the API that can definitely improve. At the very least, we could do the saving of the file on iOS for you.

[kaciula]

This also happens for MacOS and Windows. You need to save the file once you get the output path.

[jahertor]

Thanks for your solution, I was going crazy. Could this be a good approach for all platforms?

final file = File(outputFile);
if (!file.existsSync()) {
    file.writeAsBytes(bytes);
}

Because file.isBlank returns false, I don't know why.