Show more button in ngFor in angular2

Question

I have a list of over 50 items. I would like to show only the first 10 items, and I would have a button that when clicked shows the next 10 items, and which clicked again, the next 10 items until all is shown.

<ul class="results-main-content">
  <li class="right-results-section">
    <ul class="_result-list">
      <li class="result" *ngFor="let searchResult of searchResults">
        {{searchResult.name}}
      </li>
    </ul>
  </li>
  <li class="showmore">
    <button class="show-more">
      <img class="more" src="_arrow-down.svg" alt="" />
    </button>
  </li>
</ul>

Is this possible to achieve in angular2?

If so, please enlighten me and the SO community.

Thanks

Solution 1

You should use the below code

import {Component, NgModule} from '@angular/core'
import {BrowserModule} from '@angular/platform-browser'

@Component({
  selector: 'my-app',
  template: `
    <div>
      <h2>Hello {{name}}</h2>
      <ul class="results-main-content">
  <li class="right-results-section">
    <ul class="_result-list">
      <li class="result" *ngFor="let item of content">
        {{item.colorName}}
      </li>
    </ul>
  </li>
  <li class="showmore">
    <button class="show-more" (click)="getData()" [disabled]="counter>=content.length">
      Show more
    </button>
  </li>
</ul>
    </div>
  `,
})
export class App {
  name:string;
  data = [...]; // refer plunker
  content:any[]=new Array();
  counter:number;
  constructor() {
    this.counter=0;
    this.getData();
    this.name = 'Angular2'
  }
  getData(){
    console.log(this.counter + 'dat size'+this.data.length)

    for(let i=this.counter+1;i<this.data.length;i++)
    {
    this.content.push(this.data[i]);
    if(i%10==0) break;
    }
    this.counter+=10;

  }
}

@NgModule({
  imports: [ BrowserModule ],
  declarations: [ App ],
  bootstrap: [ App ]
})
export class AppModule {}

LIVE DEMO

Solution 2

You can use the slice pipe:

show = 5;

<li *ngFor="let searchResult of searchResults|slice:0:show let i=index">
  {{searchResult.name}}
  <button *ngIf="i==4 && show == 5" (click)="show = searchResults.length">More</button>
</li>

Plunker example

See also

• How to show 1 element in ngFor in angular2?

Solution 3

By modifying Günter Zöchbauer code, you can achieve this by looking at this example

import { Component } from '@angular/core';

@Component({
  selector: 'my-app',
  template: `
<ul>  
 <li *ngFor="let tag of tags | slice:0:show; let i=index">
  <a href="#" class="span-tag tag">{{ tag }}</a>
 </li>
<div *ngIf="show < tags.length" (click)="increaseShow()">DropDown Button</div>
</ul>
`,
  styleUrls: [ './app.component.css' ]
})
export class AppComponent  {
  name = 'Angular';

  show = 10;
  tags = ['a','b','c','d','e','f','g','h','i','j','a','b','c','d','e','f','g','h','i','j', 'a','b','c','d','e','f','g','h','i','j','a','b','c','d','e','f','g','h','i','j', 'a','b','c','d','e','f','g','h','i','j'];

  increaseShow() {
   this.show += 10; 
 }
}

stackblitz example

Comments

[DingDong]

How would I ensure that it only shows 10 items on click?

[Aravind]

see the if condition inside the for loop

[DingDong]

I believe its not the condition in for loop. Its the condition that we assign in the [diabled] handler.

[DingDong]

Because when you click the button, its says that view al of it. But thats not what i want. What i want is to only show 10 items for every click that the suer does

[DingDong]

So basically, by default the first 10 item should be shown. And when you click on the button, the next 10 item is shown. When click again, the next 10 item is shown.

[DingDong]

So basically, for each click, you show the next 10 items until there is no more left

[Aravind]

Let us continue this discussion in chat.