Android : Wait for cordova FileTransfer to be done

I am downloading the entire app with cordova filetransfer localy on the device and then redirect the index to the downloaded location.

But my issue is that i can't seem to find any solution for waiting for the filetransfer to be done before redirecting.

Her is my code for downloading:

 window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, function(fileSystem) {
    var fileTransfer = new FileTransfer();


    var downloadUrl = "http://example.com/index.html";
    var relativeFilePath = "example/index.html";
    fileTransfer.download(downloadUrl, localpath = fileSystem.root.toURL() + '/' + relativeFilePath, function(entry) {
            console.log("Success");
        },
        function(error) {
            console.log("Error during download. Code = " + error.code);
        });

I am doing so for each file. (approx. 200 files). Maybe there is a better way of doing it, but this works.

I have tried document.ready, $.when().done() but no luck. Any advice would be appreciated.