Using Swift closure with Objective-C framework

Question

I am using the MCSwipeTableViewCell framework for swipe-able tableviewcells. One of the completion blocks inside a `cellForRowAtIndexPath` function looks like this: ``` [cell setSwipeGestureWithView:checkView color:greenColor mode:MCSwipeTableViewCellModeSwitch state:MCSwipeTableViewCellState1 completionBlock:^(MCSwipeTableViewCell *cell, MCSwipeTableViewCellState state, MCSwipeTableViewCellMode mode) { // run some function call }]; ``` I used a Bridging-Header file to import the framework into my Swift project and am attempting to use that same completion block in Swift. This is what I have: ``` cell.setSwipeGestureWithView(crossView, color: UIColor.colorFromRGB(RED), mode: MCSwipeTableViewCellMode.Switch, state:MCSwipeTableViewCellState.State1, completionBlock: { (cell: MCSwipeTableViewCell!, state: MCSwipeTableViewCellState!, mode: MCSwipeTableViewCellMode!) -> Void in self.runSomeFunction(); }); ``` The problem is, it crashes everytime I run `self.runSomeFunction()` even though th…

Accepted Answer

You can define a Capture List to use `self` inside a Closure like this:

```
cell.setSwipeGestureWithView(crossView, color: UIColor.colorFromRGB(RED), mode: MCSwipeTableViewCellMode.Switch, state:MCSwipeTableViewCellState.State1) {
    [unowned self]
    cell, state, mode in
    self.runSomething()
}
```

Currently `[unowned self]` may crash sometimes so for the time being use `[weak self]` and inside your closure unwrap `self` like: `self!.doSomething()`.

Using Swift closure with Objective-C framework

Solution

Problem