Question

I’m creating a custom file type in AIR, which is a zip file under a different extension. I’ve been trying a few libs out, and settled on Fzip. This is to house my apps project files.

The tests seem to run OK, apart from occasionally getting ‘Unknown record signature’ Error.
I’m wondering if I’m missing something, and perhaps someone can shed some light. First time I’ve attempted something like this.

It seems to occur randomly, I have a basic app which allows you to add new files at runtime. Contents display in a list and upon select you view the text content.
From time to time when adding a new file, saving, then reopening I get this unknown record error. The main functions which could be the cause

    private function openComplete( event:Event ):void {
        _zipFile.loadBytes( _file.data );
        dispatch( new ZipServiceEvent( ZipServiceEvent.CONTENTS_CHANGE ) );
    }
    public function saveFile( event:Event=null ):void {
        if( _file.isDirectory ) {
            browseForSave();
            return void;
        }
        if ( _file.extension != _ext )
            _file = new File( _file.nativePath + _ext );
        var stream:FileStream = new FileStream();
        stream.open( _file, FileMode.WRITE );
        _zipFile.serialize( stream );
        stream.close();
    }
    public function getFile( name:String ):FZipFile {
        return _zipFile.getFileByName( name );
    }

    public function addFile( name:String, contents:ByteArray ):void {
        _zipFile.addFile( name, contents );
    }
    private function saveFileHandler( event:Event ):void {
        var contents:ByteArray = new ByteArray();
        contents.writeMultiByte( view.filecontents.text, 'utf-8' );
        model.addFile( view.filename.text, contents );
    }

Answer 1

I would need to test you class to look for errors… I wont have time to check it but in the meanwhile I´ll post an Util class I created for this purpose. It´s not very extensive, it was just for a small project but it may help you…

package com.models
{
    import com.events.AppEvent;

    import deng.fzip.FZip;

    import flash.events.Event;
    import flash.events.EventDispatcher;
    import flash.events.IEventDispatcher;
    import flash.utils.ByteArray;

    public class ZIPEncoder extends EventDispatcher
    {
        private var _zip:FZip;
        private var _compressedBytes:ByteArray = new ByteArray();

        public function ZIPEncoder(target:IEventDispatcher=null)
        {
            super(target);
        }

        public function newZip(name:String = ""):void
        {
            if(_zip) _zip = null;
            _zip = new FZip();
            _zip.addEventListener(Event.COMPLETE, onZipComplete);
        }

        public function newEntry(name:String, bytes:ByteArray):void
        {
            if(_zip == null)
            {
                throw(new Error("No zipOutput initialized. Call newZip() to initialize a new ZipOutput object before creating entry instances"));
                return;
            }
            _zip.addFile(name, bytes);
        }

        public function compress():void
        {
            _zip.serialize(_compressedBytes, false);
            dispatchEvent(new AppEvent(AppEvent.ZIP_ENCODED, _compressedBytes));
        }

        private function onZipComplete(event:Event):void
        {
            dispatchEvent(new AppEvent(AppEvent.ZIP_ENCODED, _compressedBytes));
        }
        //public function get zip():ZipOutput { return _zip; }
    }
}

hope it helps…