Auto suggest with HTML5 Data List in Vue.js 2 application image 27

Auto suggest with HTML5 Data List in Vue.js 2 application

This article shows data (News stories) retrieved from a public REST API (https://newsapi.org) in a nice and simple yet attractive Vue.js 2 application. In the example, the user selects a news source using a dropdown select component.

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I was wondering how hard – or easy – it would be to replace the select component with an input component with associated data list – a fairly new HTML5 addition that is rendered as a free format entry field with associated list of suggestions based on the input. In the case of the sample News List application, this component renders like this:

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and this if the user has typed “on”

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To change the behavior of the SourceSelection component in the sample, I first clone the original source repository from GitHub.  I then focus only on the file SourceSelection.vue in the components directory.

I have added the <datalist> tag with the dynamic creation of <option> elements in the same way as in the original <select> element. With one notable change: with the select component, we have both the display label and the underlying value. With datalist, we have only one value to associate with each option – the display label.

The input element is easily associated with the datalist, using the list attribute. The input element supports the placeholder attribute that allows us to present an initial text to the end user. The input element is two-way databound to property source on the component. Additionally, the input event – which fires after each change in the value of the input element – is associated with a listener method on the component, called sourceChanged.

I make a distinction now between the source property – which is bound to value in the input field – and the deepSource property which holds the currently selected news source object (with name, id and url). In function sourceChanged() the new value of source is inspected. If it differs from the currently selected deepSource, then we try to find this new value of source in the array of news sources. If we find it, we set that news source as the new deepsource – and publish the event sourceChanged.

The full code for the SourceSelection.vue file is here from https://gist.github.com/lucasjellema/1c92c052d3a278ee27d17cfa3ea3b54a: