如何从Vaadin7中的服务器下载文件？

Question

I have FileResource

FileResource curResource = new FileResource(new File(basepath +
                                "/WEB-INF/docs/"+path+".pdf"));

and i want save this file from browser on the computer by click the button. How can i do this in Vaadin 7? Thanks

I try something like this:

ExternalResource resource = new ExternalResource(basepath +
                                "/WEB-INF/icons/"+"block_16.png");
Page.getCurrent().open(resource.getURL(),"Download",true);

but i have empty about:blank page and nothing happens...

Answer 1

I resolve my problem!

private String basepath = VaadinService.getCurrent()
            .getBaseDirectory().getAbsolutePath();
private Button saveExcel = new Button();
Resource res = new FileResource(new File(basepath +
                "/WEB-INF/docs/settings.xlsx"));
FileDownloader fd = new FileDownloader(res);
fd.extend(saveExcel);

It's so easy to download from server in Vaadin

Answer 2

The problem of this solution is that: The file name and file content must be known before you call the fd.extend.

If you want to build the file name and file content on demand, see the tutorial in Vaadin wiki page: Letting The User Download A File