Android Question compressing list of files into a single file?

[leitor79]

Hi!

Can multiple files be compressed into one gzip? How can I do it? I've tried several things, for example:

Dim compress As CompressedStreams
.
.
.
out1=File.OpenOutput("",sFile,False)
out = File.Openoutput("", sc, True)
out=compress.WrapoutputStream(out1,"gzip")
WriteStringToStream(out, s)

With that I get 0 byte file.

I've also tried OpenInput for the file to compress (it has more sense to me since I'm not writing there) but I got errors (wrapinputstream returns an inputstream, thing I don't get it because I need an outputstream to write the file, right?)

Thank you!


PS: gzip or any format would do it.

 

[Erel]

What is WriteStringToStream? Don't use strings when working with bytes. They are not the same.

The problem with gzip is that it will create a single compressed "blob". It will be difficult to decompress it and return multiple files. You should instead use zip compression with the Archiver library.

 

[leitor79]

Hi, Erel,

Thank you very much for your answer.

That function is the one on the documentation's example:

Sub WriteStringToStream(Out As OutputStream, s As String)
    Dim t As TextWriter
    t.Initialize(Out)
    t.Write(s)
    t.Close 'Closes the internal stream as well
End Sub

I'll take a look at the archiver class.

Regards!

 

[leitor79]

Hi,

I've solved it with the Archiver library.

Arc.ZipFiles receives a list of files and put them into a single file.

Thank you for your suggestion!