Error: CdkVirtualScrollViewport is already attached about mat-vs-table

[liuy97]

Have you tried demo-project or demo-ng8?

[bubooon]

Yes, I saw demo-ng8 source code.

[bubooon]

So, I realized what a problem. If you will recreate dataSource during the app lifecycle (for example after a state of data items will change) you will have this error.
Example of code:

ngOnInit(){
  this.someObservable.subscribe(users => {
    this.dataSource = new MatTableDataSource<User>(users);
  });
}

In that case on second value from Observable you will get error.

[ForTimeBeing]

So, I realized what a problem. If you will recreate dataSource during the app lifecycle (for example after a state of data items will change) you will have this error.
Example of code:

ngOnInit(){
  this.someObservable.subscribe(users => {
    this.dataSource = new MatTableDataSource<User>(users);
  });
}

In that case on second value from Observable you will get error.

Thanks for pointing out the problem, but what if I have to recreate the datasource because of sorting? Am I unable to use this?

EDIT: The reason why mine was causing this, was because I was initilizing dataSource above(in the class) such as;

dataSource = new MatTableDataSource([]);

Then in the actual code function I recreated dataSource (since I am PULLING in the data and it is UNKNOWN during startup) Nearly every example ive seen is with known data. Anyways in the function I had
this.dataSource = new MatTableDataSource(tableArr);

[liuy97]

I guess you can do the following instead of creating new MatTableDataSource each time
this.dataSource.data = users

You assign new data after you do searching.

[ForTimeBeing]

I guess you can do the following instead of creating new MatTableDataSource each time
this.dataSource.data = users

You assign new data after you do searching.

I'm not sure if you're replying to my post, but I try not to change the data of the data source such as datasource.data . I use filtering and when changing the data, it won't filter correctly if I change the data. I would have to reload the datasource hurting performance

Edit: either way my problem is solved. It's working Amazingly. I'm having issues with sorting / resizing now. When resizing, it will also sort the column you release your mouse at while resizing.

[liuy97]

Good to know the problem gets resolved. If you can provide demo in stackblitz, I can maybe help you.

[ForTimeBeing]

Good to know the problem gets resolved. If you can provide demo in stackblitz, I can maybe help you.

It's 2:30am right now and I'm in bed but maybe tomorrow I'll see if I can set it up. I never used stack blitz but I'll check it out. Basically what is happening is that when you resize you click and hold your mouse, and if you let go in another cell, due to having matsort it also sorts at the same time. I tried adding a check to see if resizing but it isn't working correctly (to disable and enable sorting). Not only that, when resizing with a lot of elements it's very laggy. I was hoping adding this would help. It did help with scrolling A Lot but not resizing. Thanks for the help though! We're getting a bit off subject so please add me and DM me if you can. I appreciate the help again!