ionic 3 error virtual scroll

[gbelmm]

simple code

[manucorporat]

Looks like there is an issue when the number of items is == 0.

Fixed and added new tests: 5e142a0

[szerner]

@manucorporat : yes, I have these crashes too when the lists gets empty through filter operations.

[manucorporat]

@szerner @gbelmm could you guys try this new nightly release?
ionic-angular@3.0.0-201704061529

[gbelmm]

it works

[szerner]

Hm, now I get a bunch of Typescript Errors when I try to "ionic serve":

[17:33:59]  ionic-app-scripts 1.3.0
[17:33:59]  watch started ...
[17:33:59]  build dev started ...
[17:33:59]  clean started ...
[17:33:59]  clean finished in 4 ms
[17:33:59]  copy started ...
[17:33:59]  transpile started ...
[17:34:04]  typescript: ...te/proj/node_modules/ionic-angular/components/slides/slides.d.ts, line: 568
            Cannot find name 'SlideElement'.

     L567:  /** @hidden */
     L568:  clickedSlide: SlideElement;
[17:34:04]  typescript: ...te/proj/node_modules/ionic-angular/components/slides/slides.d.ts, line: 570
     L569:  /** @hidden */

            Cannot find name 'SlideContainer'.

and some more.

[szerner]

I reverted back to ionic-angular@3.0.0 for now and my app builds again.

[dtalay]

Still having issues on this.
Also having this warning message:

Virtual Scroll: Please provide an "approxItemHeight" input to ensure proper virtual scroll rendering
virtual-util.js:24 Uncaught TypeError: Cannot read property 'length' of undefined

[dtalay]

I had it surrounded with an *ngIf so that it would only show if there's an item in the array but it doesn't show. It says: Virtual Scroll: Please provide an "approxItemHeight" input to ensure proper virtual scroll rendering

[ealmiladi]

@m00g33k having the same issue with the undefined records

[amrsh]

After I updated to 3.0.1 I still got property 'top' error, but found that this was due to my list being undefined, not empty (which it was upon load even though initialized to an empty array in a separate service). In case helpful to others, this worked for me:

<ion-list [virtualScroll]="list.length ? list : []">

[HashmatWaziri]

@amrsh , you are right the list needs to be defined for example :

# IONIC 3
home.html

<ion-list [virtualScroll]="results" [approxItemHeight]="'132px'">
<ion-item *virtualItem="let result;let i=index" >
<h2 ion-text left> {{ i+1}} &nbsp; {{ result.title}}</h2>
<p>{{result.ReleaseDate}} </p>
<ion-icon item-right></ion-icon>
<ion-icon (click)="download(result.audio, result.file_name)" item-right name="download" >
</ion-icon>
<ion-icon item-right (click)="open(result.file_name)" name="play"></ion-icon>
</ion-item>
</ion-list>

home.ts

export class HomePage {
constructor(public navCtrl: NavController) {
this.results = [];
this._unfilteredResults = [];
this._usesFilter = false;
}
......
'}'

[Douglasfeuser]

still getting this error, is there any fix or workaround for this? i'm using version 3.1.2.

[bumble-bee-chuna]

Seconding what @Douglasfeuser said

[ionitron-bot]

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