如何防止在引导模式中失去焦点？

Question

看看 boostrap 网站本身：

http://getbootstrap.com/javascript/#modals-related-target

虽然它与本段中的主题无关，但您可以打开带有输入字段的模式并尝试以下操作：聚焦输入字段，键入一些字符，切换到另一个窗口或浏览器选项卡，然后来回到模态。在 Firefox 中，焦点输入不再是焦点。

如何重新聚焦最后一个聚焦的元素？或者我怎么能防止焦点丢失？

更新：提交了一个问题on GitHub。

Answer 1

除了@SHAZ 解决方案，您还需要$(window).focus() 函数在浏览器选项卡处于活动状态时聚焦输入

$(function(){
   $('#myModal').on('shown.bs.modal', function () {
      $('#myTextId').focus()
   });
});

$(window).focus(function () {
   var input = document.getElementById("myTextId").focus();
});

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" />
      
<!-- Button trigger modal -->
<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#myModal">
  Launch demo modal
</button>

<!-- Modal -->
<div class="modal fade" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel">
  <div class="modal-dialog" role="document">
    <div class="modal-content">
      <div class="modal-header">
        <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>
        <h4 class="modal-title" id="myModalLabel">Modal title</h4>
      </div>
      <div class="modal-body">
        <input type="text" id="myTextId" class="form-control" autofocus/>
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>


<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>

Fiddle

Answer 2

当 bootstrap's modal 每次打开时，只需 focus() 您的输入字段。为此使用以下代码：

$(function(){
   $('#myModal').on('shown.bs.modal', function () {
      $('#myTextId').focus()
   });
});

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" />
      
<!-- Button trigger modal -->
<button type="button" class="btn btn-primary btn-lg" data-toggle="modal" data-target="#myModal">
  Launch demo modal
</button>

<!-- Modal -->
<div class="modal fade" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel">
  <div class="modal-dialog" role="document">
    <div class="modal-content">
      <div class="modal-header">
        <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>
        <h4 class="modal-title" id="myModalLabel">Modal title</h4>
      </div>
      <div class="modal-body">
        <input type="text" id="myTextId" class="form-control" autofocus/>
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>


<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>

Answer 3

我一直致力于解决此类问题的可访问性修复（通过模态弹出保持键盘焦点）。

这是我的代码：

$("Your modal id").on('shown.bs.modal', function(event) {
    window.setTimeout(function(){
        $('.close').focus();
    }, 1000);
});

上面的代码将在模态弹出窗口中聚焦指向 CLOSE (X) 图标的指针。

使用模态保持焦点（键盘标签导航）：

一旦标签焦点到达关闭按钮：

 <a class="btn btn-default grey_btn" align="center" data-dismiss="modal" onkeydown="focusToClose(event);" href="#" target="_self"><span class="text">Close</span></a>

    function focusToClose(e)
    {
        if((e.key == 'Tab' || e.code == 'Tab') && !e.shiftKey)
        {
            e.preventDefault();
             $('#closeIcon').focus();
        }
    }

CLOSE (X) 按钮代码：

<button type="button" onKeyDown="blockFocus(event);" class="close" id="closeIcon" data-dismiss="modal" aria-label="Close">
    <span aria-hidden="true">&times;</span>
</button>

编码愉快.. :)