Best way to do a split pane in HTML [closed]

Answer 1

In the old days, you would use frames to achieve this. There are several reasons why this approach is not so good. See Reece's response to Why are HTML frames bad?. See also Jakob Nielson's Why Frames Suck (Most of the Time).

A somewhat newer approach is to use inline frames. This has pluses and minuses as well: Are iframes considered 'bad practice'?

An even better approach is to use fixed positioning. By placing the navigation content (e.g. the favorites links in your example) in a block element (like a div) then applying position:fixed to that element and setting the left, top and bottom properties like this:

#myNav {
    position: fixed;
    left: 0px;
    top: 0px;
    bottom: 0px;
    width: 200px;
}

... you will achieve a vertical column down the left side of the page that will not move when the user scrolls the page.

The rest of the content on the page will not "feel" the presence of this nav element, so it must take into account the 200px of space it occupies. You can do this by placing the rest for the content in another div and setting margin-left:200px;.

Answer 2

Simplest HTML + CSS accordion, with just CSS resize.

div {
  resize: vertical;
  overflow: auto;
  border: 1px solid
}
.menu {
  display: grid
  /* Try height: 100% or height: 100vh */
}

<div class="menu">
  <div>
    Hello, World!
  </div>
  <div>
    Hello, World!
  </div>
  <div>
    Hello, World!
  </div>
</div>

---

Simplest HTML + CSS vertical resizable panes:

div {
  resize: horizontal;
  overflow: auto;
  border: 1px solid;
  display: inline-flex;
  height: 90vh
}

<div>
  Hello, World!
</div>
<div>
  Hello, World!
</div>

---

The plain HTML, details element!.

<details>
  <summary>Morning</summary>
  <p>Hello, World!</p>
</details>
<details>
  <summary>Evening</summary>
  <p>How sweat?</p>
</details>

---

Simplest HTML + CSS topbar foldable menu

div{
 display: flex
}
summary,p{
 margin: 0px 0 -1px 0px;
 padding: 0 0 0 0.5rem;
 border: 1px black solid
}
summary {
  padding: 0 1rem 0 0.5rem
}

<div>
  <details>
    <summary>FILE</summary>
    <p>Save</p>
    <p>Save as</p>
  </details>
  <details>
    <summary>EDIT</summary>
    <p>Pump</p>
    <p>Transfer</p>
    <p>Review</p>
    <p>Compile</p>
  </details>
  <details>
    <summary>PREFERENCES</summary>
    <p>How sweat?</p>
    <p>Powered by HTML</p>
  </details>
</div>

---

Fixed bottom menu bar, unfolding upward.

div{
 display: flex;
 position: fixed;
 bottom: 0;
 transform: rotate(180deg)
}
summary,p{
 margin: 0px 0 -1px 0px;
 padding: 0 0 0 0.5rem;
 border: 1px black solid;
 transform: rotate(180deg)
}
summary {
  padding: 0 1rem 0 0.5rem;
}

<div>
  <details>
    <summary>FILE</summary>
    <p>Save</p>
    <p>Save as</p>
  </details>
  <details>
    <summary>EDIT</summary>
    <p>Pump</p>
    <p>Transfer</p>
    <p>Review</p>
    <p>Compile</p>
  </details>
  <details>
    <summary>PREF</summary>
    <p>How?</p>
    <p>Power</p>
  </details>
</div>

---

Simplest resizable pane, using JavaScript.

let ismdwn = 0
rpanrResize.addEventListener('mousedown', mD)

function mD(event) {
  ismdwn = 1
  document.body.addEventListener('mousemove', mV)
  document.body.addEventListener('mouseup', end)
}

function mV(event) {
  if (ismdwn === 1) {
    pan1.style.flexBasis = event.clientX + "px"
  } else {
    end()
  }
}
const end = (e) => {
  ismdwn = 0
  document.body.removeEventListener('mouseup', end)
  rpanrResize.removeEventListener('mousemove', mV)
}

div {
  display: flex;
  border: 1px black solid;
  width: 100%;
  height: 200px;
}

#pan1 {
  flex-grow: 1;
  flex-shrink: 0;
  flex-basis: 50%; // initial status
}

#pan2 {
  flex-grow: 0;
  flex-shrink: 1;
  overflow-x: auto;
}

#rpanrResize {
  flex-grow: 0;
  flex-shrink: 0;
  background: #1b1b51;
  width: 0.2rem;
  cursor: col-resize;
  margin: 0 0 0 auto;
}

<div>
  <div id="pan1">MENU</div>
  <div id="rpanrResize">&nbsp;</div>
  <div id="pan2">BODY</div>
</div>

Answer 3

I wanted a vanilla, lightweight (jQuery UI Layout weighs in at 185 KB), no dependency option (all existing libraries require jQuery), so I wrote Split.js.

It weights less than 2 KB and does not require any special markup. It supports older browsers back to Internet Explorer 9 (or Internet Explorer 8 with polyfills). For modern browsers, you can use it with Flexbox and grid layouts.

Answer 4

I found a working splitter, http://www.dreamchain.com/split-pane/, which works with jQuery v1.9. Note I had to add the following CSS code to get it working with a fixed bootstrap navigation bar.

fixed-left {
    position: absolute !important; /* to override relative */
    height: auto !important;
    top: 55px; /* Fixed navbar height */
    bottom: 0px;
}

Answer 5

You can do it with jQuery UI without another JavaScript library. Just add a function to the .resizable resize event to adjust the width of the other div.

$("#left_pane").resizable({
  handles: 'e', // 'East' side of div draggable
  resize: function() {
    $("#right_pane").outerWidth( $("#container").innerWidth() - $("#left_pane").outerWidth() );
  }
});

Here's the complete JSFiddle.

Answer 6

You can use absolute of fixed positioning. This CSS for example will dock a 2em-bar on the left side of your page:

body {
    padding-left: 2.5em;
}
body > #bar {
    position:fixed;
    top:0; left:0;
    width: 2em;
    height: 100%;
    border-right: 2px solid #55F; background: #ffffd;
}

(Demo at jsfiddle.net)