ios - 将子 Controller 添加到 TableView 单元格时不会调用 viewWillAppear

Question

当我将 subview Controller 添加到 TableView 单元格时，似乎没有调用 subview Controller 的 viewWillAppear，只有 viewDidAppear。

TableView Controller 方法:

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
{
    let cell = tableView.dequeueReusableCellWithIdentifier("ShopInfoTableViewCell", forIndexPath: indexPath) as! ShopInfoTableViewCell
    self.addChildViewController(self.shopInfoViewController, toView: cell.containerView)
    return cell
}

ViewController类方法:

- (void)addChildViewController:(UIViewController *)childController toView:(UIView *)view
{
    [self addChildViewController:childController];
    [view addSubview:childController.view];
    [childController didMoveToParentViewController:self];

    [childController.view mas_makeConstraints:^(MASConstraintMaker *make) {
        make.top.equalTo(view.mas_top);
        make.bottom.equalTo(view.mas_bottom);
        make.left.equalTo(view.mas_left);
        make.right.equalTo(view.mas_right);
    }];
}

知道为什么会这样吗？

Answer 1

- (void)addChildViewController:(UIViewController *)childController toView:(UIView *)view
{
    [self addChildViewController:childController];

    //add this
    [childController beginAppearanceTransition:YES animated:YES];
    [view addSubview:childController.view];
    [childController endAppearanceTransition];

    [childController didMoveToParentViewController:self];

    [childController.view mas_makeConstraints:^(MASConstraintMaker *make) {
        make.top.equalTo(view.mas_top);
        make.bottom.equalTo(view.mas_bottom);
        make.left.equalTo(view.mas_left);
        make.right.equalTo(view.mas_right);
    }];
}

同样，当你想消失时，你应该调用这个

    [childController beginAppearanceTransition:NO animated:YES];
    [childController.view removeFromSuperview];
    [childController endAppearanceTransition];