IOS7 navgationbar遮挡下面的View的问题

转自http://www.haogongju.net/art/2282067，原始的原文从哪里来，没有追查过。原文是英文的，大概意思如下：

使用navigationController、navgationbar过程中，会出现在IOS6及以下效果如图1，在IOS7上效果如图2，出现了navgationbar遮挡下面的View的问题。



图1



图2

解决办法：按原文描述在IOS7下在viewLoad事件中增加：

<code><span class="pln">self</span><span class="pun">.</span><span class="pln">edgesForExtendedLayout </span><span class="pun">=</span><span class="typ">UIRectEdgeNone</span><span class="pun">;</span><span class="pln">
self</span><span class="pun">.</span><span class="pln">automaticallyAdjustsScrollViewInsets </span><span class="pun">=</span><span class="pln"> NO</span><span class="pun">;</span></code>

OR

<code><span class="pln">self</span><span class="pun">.</span><span class="pln">edgesForExtendedLayout </span><span class="pun">=</span><span class="typ">UIRectEdgeNone</span><span class="pun">;</span><span class="pln">
self</span><span class="pun">.</span><span class="pln">extendedLayoutIncludesOpaqueBars </span><span class="pun">=</span><span class="pln"> YES</span><span class="pun">;

在实际使用过程中，以上代码在IOS5下运行时直接非法，程序闪退，原因在IOS5下不支持</span></code><pre class="lang-c prettyprint prettyprinted" name="code" style="white-space: pre-wrap; word-wrap: break-word;"><code><span class="pun"></span><span class="pln">edgesForExtendedLayout，至于IOS6如何本人手边没这个版本的IOS不好判断。因此本人做了修正，代码如下：

<span style="color: rgb(255, 0, 0);">float ver =[[[UIDevice currentDevice] systemVersion] floatValue];
    if(ver>=7.0)
    {
        self.edgesForExtendedLayout =UIRectEdgeNone;
        self.automaticallyAdjustsScrollViewInsets = NO;
    }</span>
</span></code>

即先判断IOS的版本是否>=7,再执行，IOS7以下的这段代码无需执行。