根据行号替换“行”和“行反转”

I am trying to create a responsive layout with Flexbox which allows me to alternate both the directions row and row-reverse.

我正在尝试用Flexbox创建一个响应式布局，它允许我交替方向行和行反向。

Maybe you can understand it better with some image (mind the order of the boxes):

也许你可以通过一些图片(注意盒子的顺序)更好地理解它:

And resizing:

和调整:

Or still:

或者还是:

You can imagine an arrow that goes through each box, it must be possible to go through 1 to 8 following the sequence of numbers (like a snake).

你可以想象一个箭头穿过每一个盒子，它必须能够按照数字序列(像一条蛇)经过1到8。

How can I achieve it using flexbox?

我如何使用flexbox实现它?

I think I can use the order CSS property, but I miss a dynamic way to set it. I don't think I can achieve this result with JavaScript since there's no a way to get the dynamic row's number (except with ugly hacks, and I want to avoid them). So, do you have any idea?

我想我可以使用order CSS属性，但是我错过了一个动态设置的方法。我不认为我可以用JavaScript实现这个结果，因为没有办法获得动态行号(除了一些难看的技巧，我想避免它们)。你知道吗?

Thank you.

谢谢你！

If you want to write an example based on my code, you can use this:

如果你想根据我的代码写一个例子，你可以这样:

.flexbox-container {
  display: flex;
  flex-wrap: wrap;
}

.flex-item {
  width: 380px;
  height: 100px;
  background: red;
  margin: 5px;
  
  font-family: sans-serif;
  color: white;
  text-align: center;
  font-size: 2em;
  line-height: 150%;
}

<div class="flexbox-container">
  <div class="flex-item">1</div>
  <div class="flex-item">2</div>
  <div class="flex-item">3</div>
  <div class="flex-item">4</div>
  <div class="flex-item">5</div>
  <div class="flex-item">6</div>
  <div class="flex-item">7</div>
  <div class="flex-item">8</div>
</div>

2 个解决方案

#1

Given the fact the items have a known width, this can be done using order and media queries, not with row/reverse-row, unless each row has a wrapper, which won't be possible in your case.

考虑到项目具有已知的宽度，这可以使用order和media查询完成，而不是使用row/reverse row，除非每一行都有一个包装器，这在您的情况下是不可能的。

Stack snippet

堆栈段

body {margin: 0}

.flexbox-container {
  display: flex;
  flex-wrap: wrap;
}

.flex-item {
  width: 380px;
  height: 100px;
  background: red;
  margin: 5px;
  font-family: sans-serif;
  color: white;
  text-align: center;
  font-size: 2em;
  line-height: 150%;
}
@media (min-width: 796px) {
  .flex-item:nth-child(3)   { order: 2; }
  .flex-item:nth-child(4)   { order: 1; }
  .flex-item:nth-child(n+5) { order: 2; }  
  .flex-item:nth-child(7)   { order: 4; }
  .flex-item:nth-child(8)   { order: 3; }
}
@media (min-width: 1176px) {
  .flex-item:nth-child(3)   { order: 0; }
  .flex-item:nth-child(4)   { order: 3; }
  .flex-item:nth-child(5)   { order: 2; }
  .flex-item:nth-child(6)   { order: 1; }
  .flex-item:nth-child(n+7) { order: 3; }
  .flex-item:nth-child(8)   { order: 3; }
}
@media (min-width: 1556px) {
  .flex-item:nth-child(3)   { order: 0; }
  .flex-item:nth-child(4)   { order: 0; }
  .flex-item:nth-child(5)   { order: 4; }
  .flex-item:nth-child(6)   { order: 3; }
  .flex-item:nth-child(7)   { order: 2; }
  .flex-item:nth-child(8)   { order: 1; }
}

<div class="flexbox-container">
  <div class="flex-item">1</div>
  <div class="flex-item">2</div>
  <div class="flex-item">3</div>
  <div class="flex-item">4</div>
  <div class="flex-item">5</div>
  <div class="flex-item">6</div>
  <div class="flex-item">7</div>
  <div class="flex-item">8</div>
</div>

---

If the size of the items are not known, here is a jQuery version.

如果不知道条目的大小，这是jQuery版本。

Note, assigning the order value needs to be done in one go, or else it won't work, as if to start changing value for one item at a time, that change will be executed immediately and will affect the next items position.

注意，分配订单值需要一次性完成，否则它将不起作用，就像每次开始更改一个项目的值一样，该更改将立即执行，并将影响下一个项目的位置。

Codepen demo

Codepen演示

Stack snippet

堆栈段

(function ($) {
  //  preload object array to gain performance
  var $items = $('.flexbox-container .flex-item');
    
  //  run at resize
  $( window ).resize(function() {
    $.fn.setOrder(false,0);   
  });

  $.fn.setOrder = function(reverse,idx) {

    var $order = [];
    
    $items.each(function(i, obj) {    

      //  did top value changed
      if (i != 0 && $items.eq(i - 1).offset().top != $(obj).offset().top) {
        reverse = !reverse;
        //  insert index when reverse
        idx = i;
      }
      if (reverse) {
        $order.splice(idx, 0, i);
      } else {
        $order.push(i);
      }
    });
    
    //  set item's order
    $items.css('order', function(i, val) {
        return $order[i];
    });    
  }
  
  //  run at load
  $.fn.setOrder(false,0);

}(jQuery));

.flexbox-container {
  display: flex;
  flex-wrap: wrap;
}

.flex-item {
  width: 200px;
  height: 100px;
  background: red;
  margin: 5px;
  font-family: sans-serif;
  color: white;
  text-align: center;
  font-size: 2em;
  line-height: 150%;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="flexbox-container">
  <div class="flex-item">1</div>
  <div class="flex-item">2</div>
  <div class="flex-item">3</div>
  <div class="flex-item">4</div>
  <div class="flex-item">5</div>
  <div class="flex-item">6</div>
  <div class="flex-item">7</div>
  <div class="flex-item">8</div>
</div>

#2

The only way I can see this happening is by manually setting the order and then using media queries for your breakpoints - here is an example

我能看到这种情况发生的唯一方法是手动设置订单，然后对断点使用媒体查询——这里有一个例子

.flexbox-container {
  display: flex;
  flex-wrap: wrap;
}

.flex-item {
  width: calc(50% - 10px);
  height: 100px;
  background: red;
  margin: 5px;
  font-family: sans-serif;
  color: white;
  text-align: center;
  font-size: 2em;
  line-height: 150%;
}

.flex-item:nth-child(1) {
  order: 1;
}

.flex-item:nth-child(2) {
  order: 2;
}

.flex-item:nth-child(3) {
  order: 4;
}

.flex-item:nth-child(4) {
  order: 3;
}

.flex-item:nth-child(5) {
  order: 5;
}

.flex-item:nth-child(6) {
  order: 6;
}

.flex-item:nth-child(7) {
  order: 8;
}

.flex-item:nth-child(8) {
  order: 7;
}

@media only screen and (max-width: 768px) {
  .flex-item {
    width: calc(33.33333% - 10px);
  }
  .flex-item:nth-child(1) {
    order: 1;
  }
  .flex-item:nth-child(2) {
    order: 2;
  }
  .flex-item:nth-child(3) {
    order: 3;
  }
  .flex-item:nth-child(4) {
    order: 6;
  }
  .flex-item:nth-child(5) {
    order: 5;
  }
  .flex-item:nth-child(6) {
    order: 4;
  }
  .flex-item:nth-child(7) {
    order: 7;
  }
  .flex-item:nth-child(8) {
    order: 8;
  }

<div class="flexbox-container">
  <div class="flex-item">1</div>
  <div class="flex-item">2</div>
  <div class="flex-item">3</div>
  <div class="flex-item">4</div>
  <div class="flex-item">5</div>
  <div class="flex-item">6</div>
  <div class="flex-item">7</div>
  <div class="flex-item">8</div>
</div>