ios - UINavigationControllerDelegate 的方法还不够

Question

UINavigationControllerDelegate 只有 2 个委托(delegate)方法可以使用:

• navigationController:willShowViewController:
• navigationController:didShowViewController:

但是，如果我想在使用手势交互弹出 viewController 时被调用怎么办？像这样的东西:

• navigationController:willStartDragging:
• navigationController:isDraggingWithPercentage:

协议(protocol)中没有这样的委托(delegate)方法。我怎样才能得到这些方法？

Answer 1

您可以像这样向导航 Controller 的 interactivePopGestureRecognizer 添加目标/操作:

[navigationController.interactivePopGestureRecognizer addTarget:self action:@selector(handleInteractivePop:)];

然后跟踪手势的状态

- (void)handleInteractivePop:(UIScreenEdgePanGestureRecognizer *)recognizer {
    switch (recognizer.state) {
        case UIGestureRecognizerStateBegan:
            // Started Dragging
            break;

        case UIGestureRecognizerStateChanged:
            CGFloat percentComplete = [recognizer locationInView:yourView].x / yourView.frame.size.width;
            // Do something
            break;

        case UIGestureRecognizerStateEnded:
            // Released
            break;

        default:
            break;
    }
}