Prevent the dropdown menu overlap the div below just push it-CodePudding

I have a dropDown menu and when the drop list is open is overlapping the div below, I wish to push the div below down when the dropdown is open, I've try with flex, grid, flexgrow, grid rows, positions relative/absolute, and I can't find any solution.

here is the HTML code:

<div class="container">
    <div class="dropContainer">
      <div class="dropdown">
      <button onclick="myFunction()" class="dropbtn">Dropdown</button>
        <div id="myDropdown" class="dropdown-content">
          <a href="#home">Home</a>
          <a href="#about">About</a>
          <a href="#contact">Contact</a>
        </div>
      </div>
    </div>
    <div class="inputContainer">
      <label for="fname">First name:</label>
      <input type="text" id="fname" name="fname" />
    </div>
</div>

and the CSS:

.container{
  display: flex;
  flex-direction: column;
  height: 100vh;
}

.dropContainer{
  display: block;
  height: 100%;
  margin-bottom: 2rem;
}

.inputContainer{
  display: block;
  height: 100%;
  top: 5rem;
}


 /* dropDown Menu */
.dropbtn {
  background-color: #3498DB;
  color: white;
  padding: 16px;
  font-size: 16px;
  border: none;
  cursor: pointer;
}

.dropdown {
  position: relative;
  display: inline-block;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f1f1f1;
  min-width: 160px;
  padding-bottom: 140px;
  overflow: auto;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

.dropdown-content a {
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
}

.show {display: block; }

and here is the code example working: https://codepen.io/raulcosalux/pen/VwzGyYO

kind regards,

CodePudding user response：

Using absolute positioning will not regard for content underneath. With that being said, you have to use position: relative; on your dropdown menu in order to allow the input or any other content below to adjust when the menu opens.

function myFunction() {
  document.getElementById("myDropdown").classList.toggle("show");
}

// Close the dropdown if the user clicks outside of it
window.onclick = function(event) {
  if (!event.target.matches('.dropbtn')) {
    var dropdowns = document.getElementsByClassName("dropdown-content");
    var i;
    for (i = 0; i < dropdowns.length; i  ) {
      var openDropdown = dropdowns[i];
      if (openDropdown.classList.contains('show')) {
        openDropdown.classList.remove('show');
      }
    }
  }
}

.container{
  display: flex;
  flex-direction: column;
  height: 100vh;
}

.dropContainer{
  display: block;
  height: 100%;
  margin-bottom: 2rem;
}

.inputContainer{
  display: block;
  height: 100%;
  position: sticky;
}


 /* dropDown Menu */
.dropbtn {
  background-color: #3498DB;
  color: white;
  padding: 16px;
  font-size: 16px;
  border: none;
  cursor: pointer;
}

.dropdown {
  position: relative;
  display: inline-block;
}

.dropdown-content {
  display: none;
  position: relative;
  background-color: #f1f1f1;
  min-width: 160px;
  padding-bottom: 140px;
  overflow: auto;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

.dropdown-content a {
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
}

.show {display: block; }

<div class="container">
    <div class="dropContainer">
      <div class="dropdown">
      <button onclick="myFunction()" class="dropbtn">Dropdown</button>
        <div id="myDropdown" class="dropdown-content">
          <a href="#home">Home</a>
          <a href="#about">About</a>
          <a href="#contact">Contact</a>
        </div>
      </div>
    </div>
    <div class="inputContainer">
      <label for="fname">First name:</label>
      <input type="text" id="fname" name="fname" />
    </div>
</div>

CodePudding user response：

Change the position of the dropdown container that holds the menu to relative, then remove the padding you have on it. Remove this => padding-bottom: 140px; and change this => .dropdown-content { position: absolute; } to .dropdown-content { position: relative; }, this will push the content down below the menu element and the padding will no longer cover its content.

function myFunction() {
  document.getElementById("myDropdown").classList.toggle("show");
}

// Close the dropdown if the user clicks outside of it
window.onclick = function(event) {
  if (!event.target.matches('.dropbtn')) {
    var dropdowns = document.getElementsByClassName("dropdown-content");
    var i;
    for (i = 0; i < dropdowns.length; i  ) {
      var openDropdown = dropdowns[i];
      if (openDropdown.classList.contains('show')) {
        openDropdown.classList.remove('show');
      }
    }
  }
}

.container{
  display: flex;
  flex-direction: column;
  height: 100vh;
}

.dropContainer{
  display: block;
  margin-bottom: 2rem;
}

.inputContainer{
  display: block;
  height: 100%;
  top: 5rem;
}


 /* dropDown Menu */
.dropbtn {
  background-color: #3498DB;
  color: white;
  padding: 16px;
  font-size: 16px;
  border: none;
  cursor: pointer;
}

.dropdown {
  position: relative;
  display: inline-block;
}

.dropdown-content {
  display: none;
  background-color: #f1f1f1;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

.dropdown-content a {
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
}

.show {
  display: block;
}

<div class="container">
    <div class="dropContainer">
      <div class="dropdown">
      <button onclick="myFunction()" class="dropbtn">Dropdown</button>
        <div id="myDropdown" class="dropdown-content">
          <a href="#home">Home</a>
          <a href="#about">About</a>
          <a href="#contact">Contact</a>
        </div>
      </div>
    </div>
    <div class="inputContainer">
      <label for="fname">First name:           </label>
      <input type="text" id="fname"             name="fname" />
    </div>
</div>

I also removed the height on the dropContainer as well.