blocks|key|4232848|text|你有没有试过使用PopBackStackImmediate的this重载？这将弹出所有片段，直到您在字符串中指定的片段为止(如果传递了包含标志，那么该片段也将被弹出)，因此您可以在片段后台堆栈中遍历所有片段。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4232849|Activity.SupportFragmentManager.PopBackStackImmediate("myViewTag",+(int)PopBackStackFlags.Inclusive);|code-block|syntax|javascript|4232850|其中"myViewTag"是视图的UniqueImmutableCacheTag|4232851|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.xamarin.com/api/member/Android.App.FragmentManager.PopBackStackImmediate/p/System.String/Android.App.PopBackStackFlags/^0|8|L|U|4|0|0|0|2|B|H|N|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@$9|X|A|Y|1|Z]]|E|$]]|$1|F|3|G|5|H|7|10|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|11|8|@$9|12|A|13|B|C]|$9|14|A|15|B|C]]|D|@]|E|$]]|$1|M|3|-4|5|6|7|16|8|@]|D|@]|E|$]]]|N|$O|$5|P|Q|R|E|$S|T]]]]

Have you tried using <a href="https://developer.xamarin.com/api/member/Android.App.FragmentManager.PopBackStackImmediate/p/System.String/Android.App.PopBackStackFlags/" rel="nofollow noreferrer">this</a> overload of <code>PopBackStackImmediate</code>? This one will pop all of the fragments until the one you specify in the string (if inclusive flag is passed, then that fragment is also popped) so you spare iterating all over the fragment backstack.

<pre><code>Activity.SupportFragmentManager.PopBackStackImmediate("myViewTag", (int)PopBackStackFlags.Inclusive);
</code></pre>

where <code>"myViewTag"</code> is the <code>UniqueImmutableCacheTag</code> of your View

blocks|key|4232910|text|我的实现必须有一些非常规的东西，但在最后期限和社区的帮助很少的情况下，你会做什么来修复你的hack，而不是更多的hack？|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4232911|我的解决方案有两个:+1)我实现了一个while循环，条件是:+activity.SupportFragmentManager.BackStackEntryCount+>+0，在主体中调用FragmentManager.PopBackstackImmediate(fragment.ViewModel)，而不是使用Close()。这应该已经修复了错误，但是它没有。2)我请求关闭的ViewModels仍然没有被释放，所以我必须解析当前的IMvxMultipleViewModelCache，并使用预期的参数调用GetAndClear。这迫使我的ViewModels被释放，以便在下次查看它的片段时重新创建它们。|4232912|这感觉像是黑客攻击。关闭一个ViewModel应该处理掉它，不管它是与片段还是活动相关联的，但出于某种原因，它不是。这是这个bug的关键，但就像我说的，deadline，hack+on+hack。|4232913|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

There has to be something unconventional about my implementation, but with a deadline and little help from the community, what do you do to fix your hack, but to hack it more?

My solution was twofold: 
1) instead of using FragmentManager.PopBackstackImmediate(), I implemented a while loop with the condition: activity.SupportFragmentManager.BackStackEntryCount > 0, calling Close(fragment.ViewModel) in the body. This should have fixed the bug, but it didn't. 
2) The ViewModels I was requesting to Close were still not being disposed, so I had to resolve the current IMvxMultipleViewModelCache and call GetAndClear on it with the expected parameters. This forced my ViewModels to be disposed so they will be recreated on the next viewing of its Fragment. 

This feels like a hack. Closing a ViewModel should dispose of it whether it's associated with a Fragment or Activity, but for some reason it wasn't. That's the key to this bug, but like I said, deadline, hack on hack.

I have built a Xamarin Android app that presents the user with a series of data entry forms, like a wizard. The wizard has a bottom navigation bar with previous and next buttons, and a menu button that when pressed displays a list of all forms in the wizard and allows the user to jump to any given form. 
The desired functionality is to preserve the linear navigation, so that when the user jumps to the middle of the wizard, they can still use the previous and next buttons to page through the various forms in order. They should also be able to use the hardware back button to view the previous form in the wizard. 
I suspect my implementation is not MvvmCross friendly because I'm seeing some bugs with it, specifically my viewmodels are not destroyed when I clear the fragment backstack (wizard hosted in an Activity, each form is a Fragment).

How should I implement this?

MvvmCross ViewModels not destroyed on FragmentManager.PopBackstackImmediate()

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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问在FragmentManager.PopBackstackImmediate()上未销毁MvvmCross ViewModels
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