Upload files using GWT Request Factory

Question

Is it possible to upload file via request factory? Simple example will be really helpful.

Answer 1

Actually you can!, I have an application doing it already.

1. You need browsers supporting the FileApi (modern browsers do)
2. You have to write some jsni code to read the file content into a base64 string.
3. You will receive (asynchronously) a string which you can assign to any Bean attribute in your app and send it via RF, RPC, etc.

Here you have a copy/paste of the most significant code i use:

   public final native void readAsDataURL(MyClass that, FileUpload input) /*-{
     var files = [email protected]::getElement()().files;
     var reader = new FileReader();  
     reader.onload = function (evt) {
         [email protected]::done(Ljava/lang/String;)(evt.target.result);
     }
     reader.readAsDataURL(files[0]);
    }-*/;

It would be a comming-soon feature on my gwtupload library.