ios - 协议(protocol)不适用于容器

Question

我有一个 ViewController 和两个重叠的 ContainerViews。从其中一个 subview ，我想将选项卡更改为另一个。

我创建了一个协议(protocol):

protocol pickerDelegate {
    func changeMainContainer(index:Int)
}

在 subview 中:

class ChildViewInContainerController: UIViewController, UIPickerViewDelegate {
    var delegateStorePicker:storePickerDelegate?
    func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        self.delegatePicker?.changeMainContainer(0)
    }
}

在主视图中:

class MainViewController: UIViewController, storePickerDelegate {
    func changeMainContainer(index:Int) {
        switch index {
            case 0 :
                self.container1.hidden = true
                self.container2.hidden = false
            case 1:
                self.container1.hidden = false
                self.container2.hidden = true
            default: break;
        }
    }
}

代码有效，但未调用 changeMainContainer 函数。

Answer 1

协议(protocol):(注意我更改了符合 class 的协议(protocol))

protocol PickerDelegate: class {
    func changeMainContainer(index:Int)
}

ChildView:(将您的委托(delegate)更改为弱变量)

class ChildViewInContainerController: UIViewController, UIPickerViewDelegate {
    weak var delegateStorePicker: PickerDelegate?
}

主视图:

class MainViewController: UIViewController, PickerDelegate {

    // I don't know how you create your view
    func createChild() {
        let controller = ChildViewInContainerController()
        controller.delegateStorePicker = self

        // Your own implementation
    }
}

使委托(delegate)变弱会阻止强引用循环。