如何隐藏某些用户的栏按钮项 [英] How to hide a bar button item for certain users

问题描述

我有一个设置栏按钮项（设置为左栏按钮项）。我只想在用户登录时显示它。

I have a settings bar button item (set as left bar button item). I only want to display it if the user is logged in.

我以为我可以将以下内容用于匿名用户

I thought I could use the following for anonymous users

navigationItem.leftBarButtonItem = nil

但是怎么会我是在他们登录后立即显示的吗？

But then how would I show it as soon as they logged in?

推荐答案

您可以将leftBarButtonItem的副本存储在 strong 属性并在用户登录后将其设置回来。

You can store a copy of the leftBarButtonItem in a strong property and set it back after the users log in.

var leftBarButtonItem : UIBarButtonItem!

内部viewDidLoad

Inside viewDidLoad

self.leftBarButtonItem = UIBarButtonItem(title: "test", style:         UIBarButtonItemStyle.Plain, target: nil, action: nil)

逻辑

if loggedIn
{
    self.navigationItem.leftBarButtonItem = self.leftBarButtonItem
}
else
{
    self.navigationItem.leftBarButtonItem = nil
}

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