如何去除tabBar的上橫線和navigationBar的下橫線

今天做項目，按照需求，需要作成這個樣子。 
 
不顯示出navigationBar的那個線。

在介紹navigationBar的那個線之前，我想先說一下tabBar上方的拿刀線。

首先，我們可以打印一下tabBar上的控件們。 
得到以下控件： 
 
我們可以看到里面有一個UIImageView 高度為0.5. 
也就是那個虛線。

所以說，我們想更改tabBar的線，就對這個UIImageView操作。 
代碼來了。

<code class="hljs objectivec has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">for</span> (<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIView</span> *lineView in <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">self</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.tabBarController</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.tabBar</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.subviews</span>)
    {
        <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> ([lineView isKindOfClass:[<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImageView</span> class]] && lineView<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.bounds</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.size</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.height</span> <= <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1</span>)
        {
            <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImageView</span> *lineImage = (<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImageView</span> *)lineView;
        <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//更改線的顏色</span>
            <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//lineImage.backgroundColor = [UIColor redColor];</span>
        <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//隱藏</span>
            lineImage<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.hidden</span> = <span class="hljs-literal" style="color: rgb(0, 102, 102); box-sizing: border-box;">YES</span>;
        }
    }</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li></ul>

接下來，我們繼續說一下去除navigationBar的下橫線： 
那NavgationBar里面是不是也會有UIImageView呢 
首先我們也打印一下 navigationBar 
我們會發現，里面並沒有所謂的UIImageView: 
 
但是如果你用xcode的那個層次結構圖，你可以看到 
 
箭頭指向的就是那個UIImageView 
所以，我們只需要修改UIImageView的屬性，也就可以做到我們想要的了。 
修改NavigationBar的橫線有兩種辦法。 
1.直接修改UIImageView： 
優點：簡單粗暴，省代碼； 
缺點：navigationBar的半透明效果沒了。

<code class="hljs objectivec has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;">- (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span>)viewWillAppear:(<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">BOOL</span>)animated{

    [<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span> viewWillAppear:animated];

    [<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">self</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.navigationController</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.navigationBar</span> setBackgroundImage:[<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImage</span> new] forBarPosition:UIBarPositionAny barMetrics:UIBarMetricsDefault];
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">self</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.navigationController</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.navigationBar</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.shadowImage</span> = [<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImage</span> new];

}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li></ul>

2.利用遞歸拿到子控件中的那個橫線子控件， 
利用ViewController的生命周期，在ViewDidLoad中拿到橫線line， 
在ViewWillAppear中隱藏。 
優點：navigationBar的半透明效果存在 
缺點：代碼稍微復雜一點點。

<code class="hljs objectivec has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">@interface</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ZDProfileController</span> ()</span>
{
    <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImageView</span> * line ;
}

- (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span>)viewDidLoad {
    [<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span> viewDidLoad];
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">self</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.view</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.backgroundColor</span> = ZDColor_White;

    line = <span class="hljs-literal" style="color: rgb(0, 102, 102); box-sizing: border-box;">nil</span>;
    line = [<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">self</span> navigationBarLine:<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">self</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.navigationController</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.navigationBar</span>];
}

- (<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImageView</span> *)navigationBarLine:(<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIView</span> *)view{

    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// 符合條件返回控件</span>
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> ([view isKindOfClass:<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImageView</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.class</span>] && view<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.bounds</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.size</span><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.height</span> <= <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1.0</span>) {
        <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> (<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImageView</span> *)view;
    }
    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// 遞歸查找</span>
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">for</span> (<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIView</span> *subview in view<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.subviews</span>) {
        <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">UIImageView</span> *imageView = [<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">self</span> navigationBarLine:subview];
        <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (imageView) {
            <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> imageView;
        }
    }
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-literal" style="color: rgb(0, 102, 102); box-sizing: border-box;">nil</span>;
}
- (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span>)viewWillAppear:(<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">BOOL</span>)animated{

    [<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span> viewWillAppear:animated];
    line<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">.hidden</span> = <span class="hljs-literal" style="color: rgb(0, 102, 102); box-sizing: border-box;">YES</span>;
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li></ul>

以上就是，去除tabBar的上橫線和navigationBar的下橫線的方法。 
如果確實幫助到您，請給頂一下。 
有不懂的歡迎留言。