Ionic2: ngOnChanges not triggering
<p>I want to perform some action whenever the input value or the slider is changed, but why is ngOnchanges not getting triggered when text or range input is changed? </p>

<p>Controller:</p>

<pre><code> export class APage implements OnChanges {

      @Input() total: string;
      @Input() percentage: string;

      constructor() {

      }

      ngOnChanges(changes: {[propName: string]: SimpleChange}) {
          console.log('ngOnChanges');
      }

    }
</code></pre>

<p>Template:</p>

<pre><code> &lt;ion-list&gt;
    &lt;ion-item&gt;      
        &lt;ion-label floating&gt;Total&lt;/ion-label&gt;
        &lt;ion-input type="text" [(ngmodel)]="total"&gt;&lt;/ion-input&gt;
    &lt;/ion-item&gt;

    &lt;ion-item&gt;
        &lt;ion-label stacked&gt;Percentage: {{percentage}} %&lt;/ion-label&gt;
        &lt;ion-range [(ngModel)]="percentage" min="0" max="100"&gt;
        &lt;/ion-range&gt;
    &lt;/ion-item&gt;
&lt;/ion-list&gt;
</code></pre>

<p><strong>Update1:</strong></p>

<p>Add @Input decorater as per the suggestion which didn't help.</p>

<p><strong>Update2:</strong></p>

<p>This works:</p>

<pre><code>ion-range [(ngModel)]="percentage" min="0" max="100" (ionChange)="inputChanged()"&gt;
</code></pre>

<p>But it doesn't work for ion-input:</p>

<pre><code>&lt;ion-input type="text" [(ngmodel)]="total" (ionChange)="inputChanged()"&gt;&lt;/ion-input&gt;
</code></pre>

<p><strong>Update 3:</strong></p>

<p>It worked with keyup:</p>

<pre><code>&lt;ion-input type="text" [(ngmodel)]="total" (keyup)="inputChanged()"&gt;&lt;/ion-input&gt;
</code></pre>