Question

I’m trying to make an extension that opens the downloads manager window as a sidebar or some other way, and not a new window.

• For this, I must first stop the “Save” button, in the “Save Dialog”, from opening the downloads manager as a new window.

• And then, I must set the oncommand attribute of the button to my custom function.

What I think, could be done : (Please see the edit, instead of this)

(If I have the id of the “Save” button in the “Save dialog”, I could
removeAttribute("oncommand") and then setAttribute("oncommand", "some_other_function");

Though, I am extremely unclear about whether the updated attribute will last. If the Save dialog is opened by a openDialog call (INTERNALLY), a new one would appear every time.

• Is this the right way of doing it? What then, is the id of the “Save” button? (Also, how can I know when the “Save dialog” is opened? That is when the save button would have any meaning.)
• How else could it be done?)

EDIT :

I think it would be possible via XPCOM interfaces. Is there someway by which I can :

• Know when a download/save is initiated?
• Get access to the Save dialog that opens after the above?

Answer 1

1 – I could tell when a download started using the nsiDownloadService XPCOM interface.

var observerService = Components.classes["@mozilla.org/observer-service;1"]
                      .getService(Components.interfaces.nsIObserverService);
observerService.addObserver(this, "dl-start", false);

dl-start was the required topic id.
(I could not find where dl-start is documented in MDN. Could someone point it out, please?)

2 – I just had to set the preference browser.download.manager.showWhenStarting to false to stop Firefox from opening it’s own Download Manager in a new window.