We've created solution where user has a table with files, each entry has checkbox. He can select as many as he like and then click download button.
We are using such resource, it should allow dynamically download, depending on selected items
private StreamResource createResource(final IndexedContainer container) {
return new StreamResource(new StreamSource() {
@Override
public InputStream getStream() {
for (Object o : container.getItemIds()) {
CheckBox checkbox = (CheckBox) container.getItem(o).getItemProperty(C_CHECK_BOX).getValue();
if (checkbox.getValue()) {
selectedFiles.add(o);
}
}
// do some magic to get stream of selected files
}
}, "download.zip");
}
The problem is that only second and following click on button is giving expected restults.
It's turns out that FileDownoader is getting resource from server and then it is sending current status of component . It is the reason why first click is giving stale result.
Do you have any idea how to overcome this? Is it possible to force: first update component and then download the resource?
Many thanks Pawel
CheckBox in Vaadin is non-immediate by default, which means that it won't send a request to server when the checkbox is checked (or unchecked) on the browser. Immediate components send queued non-immediate events also to server but it seems that FileDownloader doesn't cause an event that would send non-immediate checkbox values to server.
The only thing you need to do is to set your checkboxes to be immediate when you create those:
checkBox.setImmediate(true);