Filewriter example, looping through many content items. (ex)

myFileSaver = function()
{
    self = this;
    self.state = 0;
    self.currentIndex = 0;
    self.contents = Array();
    self.filename = "mysave.txt";

    self.save = function() {
        self.state = 1;
        self.currentIndex = 0;
        window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, self.gotFS, self.fail);
    }

    self.gotFS = function(fileSystem) {
        self.state = 1;
        fileSystem.root.getFile(self.filename, {create: true}, self.gotFileEntry, self.fail);
    }

    self.gotFileEntry = function(fileEntry) {
        self.state = 2;
        fileEntry.createWriter(self.gotFileWriter, self.fail);
    }

    self.gotFileWriter = function(writer) {
        self.state = -1;
        var currentLineToWrite = self.contents[self.currentIndex];
        self.currentIndex++;

        writer.onwriteend = function(evt)
        {
            if ( self.state < 0 )
            {
                // writing out the rest of the file
                self.state = -2;
                var currentLineToWrite = self.contents[self.currentIndex];
                self.currentIndex++;
                if ( self.currentIndex > self.contents.length )
                {
                    self.state = 0; // finished.
                }
                self.write ( currentLineToWrite );
            }
        };

        // write out FIRST line
        writer.write( currentLineToWrite );
    }

    self.fail = function(error) {
        console.log(error.code);
    }
}

function onDeviceReady()
{
    var myFile = new myFileSaver();

    myFile.contents = YourFileContents.split("\n");
    myFile.save();
}