Solution 1 :

Please add or update css 

.toolbar{
    contain: inherit;
    overflow: visible;
}

Solution 2 :

There are contain property inside shadow-root with static value [ without dynamic CSS variables ] and that we can override as rule of ionic shadow-element.

example

You can go with popover option of ionic framework

Solution 3 :

I couldn’t get it working with a dropdown but instead I used the ionic popover component and just implemented something myself.

https://ionicframework.com/docs/api/popover

Problem :

i am using ionic4/angular. on-clicking on the ion-avatar a dropdown menu should display but the dropdown menu is hiding in the toolbar. i tried giving z-index but it is not working. Thanks.

stackblitz link

<ion-header>
  <ion-toolbar color="tertiary" >

    <ion-buttons slot="start">
      <ion-back-button defaultHref="/"></ion-back-button>
    </ion-buttons>

    <ion-buttons slot="end">
      <button class="btn btn-light">My Courses</button>
    </ion-buttons>

    <ion-buttons slot="end">
      <ion-button class="iconbell">
        <ion-icon name="notifications-outline" size="large"></ion-icon>
      </ion-button>
    </ion-buttons>

    <ion-buttons slot="end">
      <div class="dropdown">
        <ion-avatar class="dropdown-toggle" style="margin-right:10px;height: 5vh;width: 5vh;" id="menu1" type="button" data-toggle="dropdown">
          <img [src]="user['profpic']"> <span class="caret"></span>
        </ion-avatar>
        <ul class="dropdown-menu" role="menu" aria-labelledby="menu1">
          <li role="presentation"><a role="menuitem" href="#">HTML</a></li>
          <li role="presentation"><a role="menuitem" href="#">CSS</a></li>
          <li role="presentation"><a role="menuitem" href="#">JavaScript</a></li>
          <li role="presentation" class="divider"></li>
          <li role="presentation"><a role="menuitem" href="#">About Us</a></li>    
        </ul>
      </div>

    </ion-buttons>

  </ion-toolbar>
</ion-header>

Comments

Comment posted by maddy23285

I don’t know much about angular but you can try placing your dropdown menu code outside the tag or remove the to check if it is working.

Comment posted by Prem

no its not working

Comment posted by Prem

there is no toolbar class. can u edit the stackblitz

Comment posted by Deepak

please check given URL

Comment posted by Prem

It is working in stackblitz but not working in actual project. anyway thankyou

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