Question

Say, I have the following unordered list. The button has width: auto. How do I style the elements, so #textField would stretch as much as possible, so the width of #textField and the button would add up to 100%? I.e. #textField‘s width == (100% of width) – (button’s computed width).

<ul>
  <li>
    <input id="textField" type="text" /><input type="button" />
  </li>
</ul>

So, for example, let’s say 100% width of li is 100 pixels: if the button’s computed width is 30px, #textField‘s width would be 70px; if button’s computed width is 25px, #textField‘s width would become 75px.

Answer 1

You can quickly achieve this effect using a mixture of float and overflow: hidden:

<ul>
    <li>
        <input class="btn" type="button" value="Submit"/>
        <div class="inputbox"><input id="textField" type="text" /></div>
    </li>
</ul>

CSS:

ul { 
  list-style: none; 
  padding: 0; }
.btn { float: right; }
.inputbox { 
  padding: 0 5px 0 0;
  overflow: hidden; }
.inputbox input { 
  width: 100%;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box; }

Preview (with box-sizing): http://jsfiddle.net/Wexcode/E8uHf/546/

Here is how it looks without box-sizing: http://jsfiddle.net/Wexcode/E8uHf/