OC dispatch_after

__weak typeof(self) weakSelf = self;
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^
{
    __strong typeof(self) pThis = weakSelf;
    [pThis.backgroundView removeFromSuperview];
    pThis.backgroundView = nil;
});

Swift DispatchQueue.main.asyncAfte

DispatchQueue.main.asyncAfter(deadline: .now()+0.5, execute: 
{
    self.backgroundView()?.removeFromSuperview()
    self.setBackgroundView(backgroundView: nil)
})

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