# Ionic create a slide introduction issue

**URL:** <https://forum.ionicframework.com/t/ionic-create-a-slide-introduction-issue/103735>\
**Category:** ionic-v3\
**Created:** [August 30, 2017, 2:05pm UTC](https://forum.ionicframework.com/t/ionic-create-a-slide-introduction-issue/103735 "2017-08-30T14:05:30Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![Nulra](https://avatars.discourse-cdn.com/v4/letter/n/f6c823/32.png) [@Nulra](https://forum.ionicframework.com/u/Nulra)\
**Post date:** [August 30, 2017, 2:05pm UTC](https://forum.ionicframework.com/t/ionic-create-a-slide-introduction-issue/103735/1 "2017-08-30T14:05:30Z")

</div>

I am following the tutorial below to create a slide introduction: [https://www.joshmorony.com/creating-a-sliding-introduction-component-in-ionic-2/](https://www.joshmorony.com/creating-a-sliding-introduction-component-in-ionic-2/)

But have an error when I set below:

```
this.rootPage = 'Intro';

```

the error is:

```
ERROR Error: Uncaught (in promise): TypeError: Cannot read property 'length' of undefined
TypeError: Cannot read property 'length' of undefined 

```

Anyone know how to solve? Thanks a lot~

---

<div class="post-metadata">

**Author:** ![anna\_liebt](https://avatars.discourse-cdn.com/v4/letter/a/bc8723/32.png) [@anna\_liebt](https://forum.ionicframework.com/u/anna_liebt)\
**Post date:** [August 30, 2017, 9:35pm UTC](https://forum.ionicframework.com/t/ionic-create-a-slide-introduction-issue/103735/2 "2017-08-30T21:35:12Z")

</div>

Hello,  
it looks like that ‘Intro’ is a lazy loaded page. Is your Intro prepared for lazy loading?

Best regards, anna-liebt.

---

<div class="post-metadata">

**Author:** ![Neonic1](https://sea1.discourse-cdn.com/ionicframework/user_avatar/forum.ionicframework.com/neonic1/32/113388_2.png) [@Neonic1](https://forum.ionicframework.com/u/Neonic1)\
**Post date:** [August 30, 2017, 9:39pm UTC](https://forum.ionicframework.com/t/ionic-create-a-slide-introduction-issue/103735/3 "2017-08-30T21:39:16Z")

</div>

@Nulra look it’s @Joshmorony, maybe he can help? 😃

Where you defining `length`?

**ptrzyna** commented a day ago:  
`Adding missing environment file fixed this form me.`

> <https://github.com/angular/angular-cli/issues/5053>

Regards,  
Neonic1

---

<div class="post-metadata">

**Author:** ![Nulra](https://avatars.discourse-cdn.com/v4/letter/n/f6c823/32.png) [@Nulra](https://forum.ionicframework.com/u/Nulra)\
**Post date:** [August 31, 2017, 5:31am UTC](https://forum.ionicframework.com/t/ionic-create-a-slide-introduction-issue/103735/4 "2017-08-31T05:31:18Z")

</div>

My slide code is just hardcode as below:

```
<ion-content>
 <ion-slides pager>
  <ion-slide>
   <img src="assets/img/1_zh.jpg" width="100%" height="auto">
  </ion-slide>

  <ion-slide>  
   <img src="assets/img/2_zh.jpg" width="100%" height="auto">
  </ion-slide>

  <ion-slide>  
   <img src="assets/img/3_zh.jpg" width="100%" height="auto">
  </ion-slide>

  <ion-slide>  
   <img src="assets/img/4_zh.jpg" width="100%" height="auto">
  </ion-slide>

  <ion-slide>
   <ion-row>
    <ion-col> 
     <img src="assets/img/5_zh.jpg" width="100%" height="auto">
    </ion-col>
  </ion-row>
  <ion-row>
   <ion-col>
    <button ion-button style="background-color:#17B97E; color:#FFFFFF;" (click)="goToHome()">{{ 'Firstguide.start' | translate }}</button>
   </ion-col>
  </ion-row>    
 </ion-slide>

 </ion-slides>

</ion-content>

```

How to define the length?

---

<div class="post-metadata">

**Author:** ![arnoldparge](https://sea1.discourse-cdn.com/ionicframework/user_avatar/forum.ionicframework.com/arnoldparge/32/111355_2.png) [@arnoldparge](https://forum.ionicframework.com/u/arnoldparge)\
**Post date:** [August 31, 2017, 6:19am UTC](https://forum.ionicframework.com/t/ionic-create-a-slide-introduction-issue/103735/5 "2017-08-31T06:19:22Z")

</div>

> [@Nulra](#):
>
> this.rootPage = ‘Intro’;

remove the quote and check!

---

<div class="post-metadata">

**Author:** ![Nulra](https://avatars.discourse-cdn.com/v4/letter/n/f6c823/32.png) [@Nulra](https://forum.ionicframework.com/u/Nulra)\
**Post date:** [August 31, 2017, 6:22am UTC](https://forum.ionicframework.com/t/ionic-create-a-slide-introduction-issue/103735/6 "2017-08-31T06:22:14Z")

</div>

Hi, thanks for your reply first, after remove the quote the issue still happen:cry:

---

<div class="post-metadata">

**Author:** ![Neonic1](https://sea1.discourse-cdn.com/ionicframework/user_avatar/forum.ionicframework.com/neonic1/32/113388_2.png) [@Neonic1](https://forum.ionicframework.com/u/Neonic1)\
**Post date:** [August 31, 2017, 10:16pm UTC](https://forum.ionicframework.com/t/ionic-create-a-slide-introduction-issue/103735/7 "2017-08-31T22:16:48Z")

</div>

One of the big Ionic Youtuber’s have a tutorial on this,

> [https://www.youtube.com/watch?v=1oqlmtnbBuk](https://www.youtube.com/watch?v=1oqlmtnbBuk)

He uses the Ionic Slides as well. 😉