blocks|key|573090|text|向superview添加视图将保留该视图，从superview中删除视图将释放该视图。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|573091|[subview+retain];+//+because+next+line+will+release
[subview+removeFromSuperView];+//+released+by+superview
[otherSupView+addSubview:subview];+//+retained+by+new+superview
[subview+release];+//+because+you+retained+it+in+line+1|code-block|syntax|javascript|573092|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Adding a view to a superview retains that view, removing the view from a superview releases it. 

<pre><code>[subview retain]; // because next line will release
[subview removeFromSuperView]; // released by superview
[otherSupView addSubview:subview]; // retained by new superview
[subview release]; // because you retained it in line 1
</code></pre>

blocks|key|257503|text|为了安全起见，请在视图上保留一下，然后再按如下方式移动：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|257504|[[theView+retain]+autorelease];
[theView+removeFromSuperview];
[newSuperview+addSubview:theView];|code-block|syntax|javascript|257505|如果superview是在子视图上保留的唯一对象，那么当从superview中删除该子视图时，它将被解除分配。保留和自动释放保证视图在函数中使用时不会被释放(因为它上有一个额外的保留)。|257506|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

To be safe, put a retain on the view before you move it like so:

<pre><code>[[theView retain] autorelease];
[theView removeFromSuperview];
[newSuperview addSubview:theView];
</code></pre>

If the superview is the only object that has a retain on the subview, then the subview will be deallocated when it is removed from the superview. The retain and autorelease guarantees that the view won't be deallocated while you're using it in the function (because there is an extra retain on it).

blocks|key|607204|text|对于在调用-removeFromSuperView时是否发布视图的问题，是的，这在-removeFromSuperView下的UIView引用中有记录。它没有明确声明-addSubView:调用-removeFromSuperView，但它是隐含的，可以通过在UIView子类中重载-removeFromSuperView来测试。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|607205|因此，在这种情况下，我想不出有什么理由调用-removeFromSuperView。这样做没有内存管理的理由，所以这增加了一些代码复杂性(因此也增加了潜在的错误)，而没有什么价值。即使在我想向后面的开发人员强调这个视图正在改变视图层次结构的情况下，我也会使用注释，而不是这里的额外保留/发布。|607206|entityMap^0|5|K|15|K|2B|C|2P|K|3X|K|0|L|K|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]|$9|O|A|P|B|C]|$9|Q|A|R|B|C]|$9|S|A|T|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|X|8|@]|D|@]|E|$]]]|I|$]]

To the question of whether the view is released when <code>-removeFromSuperView</code> is called, it is, and this is documented in the UIView reference under <code>-removeFromSuperView</code>. It is not as explicitly stated that <code>-addSubView:</code> calls <code>-removeFromSuperView</code>, but it is implied and can be tested by overloading <code>-removeFromSuperView</code> in a UIView subclass.

Therefore I can think of no reason to call <code>-removeFromSuperView</code> in this case. There's no memory-management reason to do it, so this is adding some code complexity (and therefore potential errors) for little value. Even in cases where I wanted to emphasize to later developers that this view is changing view hierarchy, I would use a comment rather than the extra retain/release here.

It's not clear, to me anyway, if a UIView is automatically released from its superview if you use addSubview to add it to another view?!? I know a view can only have ONE superview but I'm not clear about how, exactly, to go about moving a subview from one superview to another.

retain view, release (from old superview), addSubview to new superview

or 

simply addSubview to new superview?

Does moving a view to new superview automatically release it from old superview?

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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对我来说还不清楚，如果您使用UIView将其添加到另一个视图中，它是否会自动从其超级视图中释放出来？！？我知道一个视图只能有一个superview，但我不清楚如何从一个superview移动到另一个超级视图。保留视图，发布(从旧的超级视图)，addSubview到新的超级视图或简单的addSubview到新的超级视图？

问将视图移动到新的superview会自动从旧的superview中释放它吗？
EN

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问将视图移动到新的superview会自动从旧的superview中释放它吗？EN