Streaming Support

Streaming allows Flash content to be loaded asynchronously. This is useful for large movies or when resources such as SWF, FLV, JPG, MP3, or XML files must be provided progressively. Instead of waiting until the entire file is available, the content can be written into a stream in parts while playback continues.

Key Notes

To load movies or resources, use a stream (TStream). Provide content by writing to the stream.
If data is written from a separate thread, use Synchronize when calling Write.
If Write returns 0, loading was canceled (for example, another movie is being loaded).
Free the stream after loading is complete, even if canceled.

Use Cases

Loading a Movie Asynchronously

Use LoadMovieUsingStream or PutMovieUsingStream to begin asynchronous loading.

Delphi Example:

var  
   MovieStream: TStream;  
begin  
   FlashPlayerControl1.LoadMovieUsingStream(0, MovieStream);  
   ContentProviderThread := TContentProviderThread.Create(MovieStream);  
end;  
 
procedure TContentProviderThread.Execute;  
begin  
   while not FStop do  
   begin  
      PrepareBuffer;  
      if FBuffer.Size > 0 then  
         DoWrite;  
   end;  
   FMovieStream.Free;  
end;

C++Builder Example:

TStream* MovieStream;  
FlashPlayerControl1->LoadMovieUsingStream(0, MovieStream);  
TContentProviderThread* ContentProviderThread = new TContentProviderThread(MovieStream);
 
void __fastcall TContentProviderThread::Execute()  
{  
   while (!FStop)  
   {  
      PrepareBuffer();  
      if (FBuffer->Size > 0)  
         DoWrite();  
   }  
   FMovieStream->Free();  
}

Loading External Resources by Full Path

To provide resources such as *.flv, *.swf, *.jpg, or *.mp3 from a full path (for example, beginning with http://), set a global handler using SetGlobalOnLoadExternalResourceHandlerEx.
In the handler, compare the URL, mark the request as handled, and write data into the provided stream.

Loading External Resources by Relative Path

When a movie loads resources by relative path (e.g., images/image1.jpg), handle the OnLoadExternalResourceEx event.
Check the passed URL, mark the request as handled, and provide the resource through the stream.

Delphi Example:

procedure TMainForm.FlashPlayerControl1LoadExternalResourceEx(  
  ASender: TObject;  
  const URL: WideString;  
  Stream: TStream;  
  var bHandled: Boolean);  
begin  
   if URL = 'images/embedded_image1.jpg' then  
   begin  
      ContentProviderThread := TContentProviderThread.Create(Stream);  
      bHandled := true;  
   end;  
end;

C++Builder Example:

void __fastcall TMainForm::FlashPlayerControl1LoadExternalResourceEx(  
      TObject *ASender,  
      const WideString URL,  
      TStream *Stream,  
      BooleanRef bHandled)  
{  
   if (URL == WideString("images/embedded_image1.jpg"))  
   {  
      TContentProviderThread* ContentProviderThread = new TContentProviderThread(Stream);  
      *bHandled = true;  
   }  
}