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Example of upload implementation
In our web application were having an upload feature. I've looked through the examples in the Vaadin Sampler and in the Book of Vaadin, but I'm looking for another approach that none of these examples cover.
Were making use of the DragAndDropWrapper and the conventional file browser. And the example I'm looking for is how to specify a file, in our case either by dropping the file in the browser or by selecting it in the file browser. and have it idle there until the user clicks an upload button. Does anyone know of an example like this?
I find the Upload component quite hard to get a grip on, and I don't know how to make an external button start a workflow that has been prepared either by the drop box or by the Upload component.
Any input on this would be very appreciated! =)
As far as I know, native upload by drag and drop is an HTML 5 feature. It can be tricked by using flash to have some more browser compatibility but you will always need a fallback to the more conservative file upload method.
Writing all this by yourself might be tricky but if that's the way you want to go I think finding a GWT library which does the all the wiring and fallback for you and wrapping it in a Vaadin component (which you may then share with the community ;) ) is your best bet.