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nsIWeakReference

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This interface gives access to a proxy object that cooperates with its referent to give clients a non-owning, non-dangling reference. Clients own the proxy, and should generally manage it with an nsCOMPtr as they would any other XPCOM object. The QueryReferent member function provides a (hopefully short-lived) owning reference on demand, through which clients can get useful access to the referent, while it still exists. This interface is scriptable.

See also: nsISupportsWeakReference

Methods

QueryReferent

Queries the referent, if it exists, and like QueryInterface, returns an owning reference to the desired interface.It is designed to look and act exactly like (a proxied) QueryInterface. Don't hold on to the produced interface permanently; that would defeat the purpose of using a non-owning nsIWeakReference in the first place.

Syntax:

void nsIWeakReference::QueryReferent(in nsIIDRef uuid,
	[iid_is(uuid), retval] out nsQIResult result) 

Parameters:

uuid: The IID of the interface being requested.

result: [out] The interface pointer to be filled in if the interface is accessible.

nsresult:

NS_OK if successful.