'[weak self]' in RXSwift closures

swift closures rx-swift
Rohan Panchal picture Rohan Panchal · Jan 25, 2016 · Viewed 12.9k times · Source

Do i need to use [weak self] within RXSwift subscribeNext closures?

I have the code:

    searchController.searchBar.rx_text.throttle(0.2, scheduler: MainScheduler.instance).subscribeNext { searchText in
        self.viewModel.searchForLocation(searchText)
    }.addDisposableTo(DisposelBag.sharedDisposelBag.disposeBag)

Do i need to modify it so that there is a [weak self] capture list at the beginning of the closure? Like this:

    searchController.searchBar.rx_text.throttle(0.2, scheduler: MainScheduler.instance).subscribeNext { [weak self] searchText in
        self?.viewModel.searchForLocation(searchText)
    }.addDisposableTo(DisposelBag.sharedDisposelBag.disposeBag)

Answer

zaph picture zaph · Jan 26, 2016

If the closure is not owned by the class you do not have to use [weak self].

In the case of in-line closures the closure is not owned by the class but by the scope it is in and will be released when the scope is left.

If the closure is passed in it may or may not be owned by the class (a property for example) and it is prudent to use [weak self] incase it is owned by the class.

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