Angular 5 Stop background scrolling when mat-sidenav-container displayed

Question

I'm creating a new Angular 5 site that has a mat-sidenav but i have an issue with it.

My mat-sidenav-container sits under my position: fixed main menu which is fine but if the page has a vertical scroll, if the mat-sidenav is displayed it too scrolls.

What i'm after is to stop the back content scrolling if the mat-sidenav is displayed but i don't know the CSS to do this as i have tried all the position

HTML

<mat-toolbar>
    <mat-icon class="subMenuIcon" (click)="sidenav.toggle()" title="Click to open the sub-menu.">reorder</mat-icon>
    <img src="./assets/images/Crest.jpg">LEARNING SITE
    <div class="emptySpace"></div>        
    <mat-icon class="loggedInIcon">person</mat-icon>
    <span style="font-size: 15px">USERNAME</span>
</mat-toolbar>
<mat-sidenav-container>
    <mat-sidenav #sidenav mode="over" opened="false">
        <div class="closeButton">
            <mat-icon (click)="sidenav.toggle()" title="Click to close the sub-menu.">clear</mat-icon>
        </div>
        <a (click)="sidenav.toggle()" routerLink="/">
            <mat-icon>person</mat-icon>
            Dashboard
        </a>
        <a (click)="sidenav.toggle()" routerLink="search">
            <mat-icon>search</mat-icon>
            Search
        </a>
    </mat-sidenav>
</mat-sidenav-container>
<router-outlet></router-outlet>

CSS

mat-sidenav {
    background-color: gray;
    margin-top: 64px;
    color: #ffffff;
    transition: 0.5s;
    padding: 7px;
}

mat-sidenav a {
    margin-top: 15px;
    margin-bottom: 15px;
    font-size: 17px;
    color: #ffffff;
    display: block;
}

mat-sidenav a:hover {
    color: #c41230;
    cursor: pointer;
}

.closeButton {
    text-align: right;
    margin-bottom: 15px;
    cursor: pointer;
}

.mat-drawer-container {
    position: static;
}

/* Moves the side-nav to below the main menu */
.mat-drawer-backdrop {
    margin-top: 64px !important;
}

Solution 1

Managed to do it with a bit of CSS. not bother that the back content scrolls but now my side-nav and backdrop do not move

CSS Used

.mat-drawer:not(.mat-drawer-side) {
    position: fixed;
}

.mat-drawer-backdrop {
    position: fixed !important;
}

Solution 2

adding fixedInViewport="true" in mat-sidenav may fix the issue, also add [style.marginTop.px]="56"

Comments

[andreas]

Note that your variable event in onWindowScroll(event) is undefined. Apply the following to the first line in method 1: @HostListener("window:scroll", ["$event"]). I used this in Angular 6+.

[eddy]

This helps keep the drawer in place , but the other line messes up everything.

[eddy]

Did you managed to avoid showing the scrollbar in the main content when the mat-sidenav is displayed?

[eddy]

I tried both options. None of them worked. Do you have any idea how to stop the scrolling on the main content when the sidenav is displayed?

[John]

It is difficult to tell without seeng your code. Maybe you can ask a question, link to this thread, and get some help from there?

[adamdport]

There's a fixedTopGap attribute you can use instead of manually setting marginTop material.angular.io/components/sidenav/api#MatSidenav

[Santosh]

It does work but with a bug. The page is scroll to the top which is not good.