Found some strange dart interface

[HaloWang]

I'm coping some cpp codes into dart

this is the source cpp codes:

BYTE* lp = r.lpbitmap;

InMemoryRandomAccessStream stream;
DataWriter dataWriter{stream};

dataWriter.WriteBytes(array_view<byte>(lp, r.dwBmpSize));
auto buffer = dataWriter.DetachBuffer();

this is what I write using dartwinrt

final List<int> bytes = ...;
final stream = InMemoryRandomAccessStream();
final DataWriter dataWriter = DataWriter.createDataWriter(stream);
dataWriter.writeBytes(bytes);
final buffer = dataWriter.detachBuffer();

I wonder could I use something like Pointer<List<int>> to write to dataWriter on the dart-side?

And why DataWriter in dart hasn't method matching WriteBytes(array_view<uint8_t const> value) on the cpp-side?

[halildurmus]

...
I wonder could I use something like Pointer<List<int>> to write to dataWriter on the dart-side?

No, you can't (and you likely meant Pointer<Uint8> instead of Pointer<List<int>>, as the latter is not a valid Dart type).

And why DataWriter in dart hasn't method matching WriteBytes(array_view<uint8_t const> value) on the cpp-side?

This project is designed to provide an idiomatic Dart projection of the WinRT APIs, which involves substantial wrapping. For the sake of idiomatic usage, the method doesn't take a parameter like Pointer<Uint8>; instead, it accepts List<int>, which serves as the equivalent counterpart.

[HaloWang]

OK, and I find I can directly use Pointer<Uint8>.asTypedList provided by dart:ffi.

This function can easily convert Pointer<Uint8> to Uint8List, which implements List<int>

final dwBmpSize = 1000;
final Pointer<Uint8> lpBitmap = arena<Uint8>(dwBmpSize);
final Uint8List bytes = lpBitmap.asTypedList(dwBmpSize);
// ...
dataWriter.writeBytes(bytes);

[halildurmus]

Nice!