Is there a way to sort results in AngularJS based on a subset of child results?

Question

Is there a way to sort results in AngularJS based on a subset of child results?

Imagine I possess the subsequent item:

{
    "bands": [{
        "name": "The Wibbles",
        "formed": 1992,
        "albums": [{
            "name": "A New Wibble",
            "songs": [{
                "name": "Song One",
                "time": "3:12"
            }, {
                "name": "Song Two",
                "time": "2:34"
            }, {
                "name": "Song Three",
                "time": "2:21"
            }, {
                "name": "Song Four",
                "time": "3:44"
            }, {
                "name": "Song Five",
                "time": "3:54"
            }]
        }, {
            "name": "The Wibbles Strike Back",
            "songs": [{
                "name": "Song Six",
                "time": "8:12"
            }, {
                "name": "Song Seven",
                "time": "7:34"
            }, {
                "name": "I Killed a Girl",
                "time": "8:21"
            }, {
                "name": "Monkey Fighters",
                "time": "7:44"
            }, {
                "name": "Funkallica",
                "time": "9:54"
            }]
        }]
    }]
}

If I were to utilize AngularJS (and possibly underscore.js), how could albums be organized by the shortest track, overall album length, or by the quickest average duration of the tracks in each album?

Subsequently, if a new band was to be introduced, how would the bands themselves be sorted based on these criteria (shortest track / album duration / average track duration)?

javascript angularjs underscore.js

Answer 1

Answer №1

Arranging number strings in ascending order can be complicated, but we can definitely handle it. Consider the example presented in the HTML code below:

<div ng-repeat="band in bands">
  <h1>{{ band.name }}</h1>
  <div ng-repeat="album in band.albums">
    <h2>{{ album.name }}</h2>
    <ul>
      <li ng-repeat="songs in album.songs">
        <h3>{{ song.name }}</h3>
        <em>{{ song.time }}</em>
      </li>
  </div>
</div>

To sort the albums based on the shortest track:

<div ng-repeat="band in bands">
  <h1>{{ band.name }}</h1>
  <div ng-repeat="album in band.albums | orderBy:shortestTrackByAlbum">
    <h2>{{ album.name }}</h2>
    <ul>
      <li ng-repeat="song in album.songs">
        <h3>{{ song.name }}</h3>
        <em>{{ song.time }}</em>
      </li>
    </ul>
  </div>
</div>

To customize the sorting using a function with Angular's orderBy, pass the function itself (not the result) to the current Scope. In this case, use `orderBy:shortestTrackByAlbum'.

$scope.bands = [...];
$scope.shortestTrackByAlbum = function(album) {
  var times = [];
  for (var i = 0; i < album.songs.length; i++) {
    var minutesAndSeconds = album.songs[i].split(':'),
        m = parseInt(minutesAndSeconds[0], 10),
        s = parseInt(minutesAndSeconds[1], 10);
    times.push(m * 60 + s);
  }
  return Math.min.apply(null, times);
};

By converting the times to seconds from the data provided, we identify the smallest number of seconds among tracks. This smallest number is then compared with the smallest numbers of other albums for sorting.

This approach allows you to create functions for various scenarios. Refer to this Plunker for a basic illustration.

For user-controlled sorting, consider implementing the following:

<select ng-model="sortingMethod"
        ng-options="m.fn as m.name for m in methods"></select>

...
  <div ng-repeat="album in albums | orderBy:sortingMethod">
...

$scope.methods = [
  {
    name: 'Shortest Track',
    fn: $scope.shortestTrackByAlbum
  },
  {
    name: 'Total Album Length',
    fn: $scope.totalAlbumLengthByAlbum
  },
  {
    name: 'Shortest Average Length',
    fn: $scope.shortestAverageLengthByAlbum
  }
];

$scope.shortestTrackByAlbum = function(album) { ... };
$scope.totalAlbumLengthByAlbum = function(album) { ... };
$scope.shortestAverageLengthByAlbum = function(album) { ... };

Explore the documentation on Angular Filters and specifically Angular's OrderBy for more insights.

Answer 2

Arranging number strings in ascending order can be complicated, but we can definitely handle it. Consider the example presented in the HTML code below:

<div ng-repeat="band in bands">
  <h1>{{ band.name }}</h1>
  <div ng-repeat="album in band.albums">
    <h2>{{ album.name }}</h2>
    <ul>
      <li ng-repeat="songs in album.songs">
        <h3>{{ song.name }}</h3>
        <em>{{ song.time }}</em>
      </li>
  </div>
</div>

To sort the albums based on the shortest track:

<div ng-repeat="band in bands">
  <h1>{{ band.name }}</h1>
  <div ng-repeat="album in band.albums | orderBy:shortestTrackByAlbum">
    <h2>{{ album.name }}</h2>
    <ul>
      <li ng-repeat="song in album.songs">
        <h3>{{ song.name }}</h3>
        <em>{{ song.time }}</em>
      </li>
    </ul>
  </div>
</div>

To customize the sorting using a function with Angular's orderBy, pass the function itself (not the result) to the current Scope. In this case, use `orderBy:shortestTrackByAlbum'.

$scope.bands = [...];
$scope.shortestTrackByAlbum = function(album) {
  var times = [];
  for (var i = 0; i < album.songs.length; i++) {
    var minutesAndSeconds = album.songs[i].split(':'),
        m = parseInt(minutesAndSeconds[0], 10),
        s = parseInt(minutesAndSeconds[1], 10);
    times.push(m * 60 + s);
  }
  return Math.min.apply(null, times);
};

By converting the times to seconds from the data provided, we identify the smallest number of seconds among tracks. This smallest number is then compared with the smallest numbers of other albums for sorting.

This approach allows you to create functions for various scenarios. Refer to this Plunker for a basic illustration.

For user-controlled sorting, consider implementing the following:

<select ng-model="sortingMethod"
        ng-options="m.fn as m.name for m in methods"></select>

...
  <div ng-repeat="album in albums | orderBy:sortingMethod">
...

$scope.methods = [
  {
    name: 'Shortest Track',
    fn: $scope.shortestTrackByAlbum
  },
  {
    name: 'Total Album Length',
    fn: $scope.totalAlbumLengthByAlbum
  },
  {
    name: 'Shortest Average Length',
    fn: $scope.shortestAverageLengthByAlbum
  }
];

$scope.shortestTrackByAlbum = function(album) { ... };
$scope.totalAlbumLengthByAlbum = function(album) { ... };
$scope.shortestAverageLengthByAlbum = function(album) { ... };

Explore the documentation on Angular Filters and specifically Angular's OrderBy for more insights.

Is there a way to sort results in AngularJS based on a subset of child results?

Answer №1

Similar questions

Changing the Class of an Element in a Different Component with Angular 2+

Top method for constructing a JSON object by combining data from two queries and a joining table

Clever method for enabling image uploads upon image selection without needing to click an upload button using JQuery

What is the reason that the Mongoose updateMany() function only functions properly when combined with .then

Updating the mat-icon in a row when a button is clicked

JavaScript and AJAX: Dynamically Create URLs

Instructions for validating an AngularJS input field using a textbox

Getting the Value of an Object in an Array in My Angular Project

Sliding the cursor downward to unveil a panel? (utilizing MooTools)

Encountering the "Error: JSON.parse: unexpected character" when trying to retrieve JSON data using AngularJS

Can ng-packagr create scripts that are compatible with running in a web browser like regular JavaScript?

"Efficiently calculate the total sum of columns in a datatable using dynamic JavaScript across

Arrangement of bootstrap and CSS library in header has an impact on the styling of h3 Tag

Struggling to find a way to connect individual points on a map

Utilizing asynchronous JavaScript imports within exported classes

Experiencing difficulties when attempting to show or hide elements using jQuery

There seems to be a problem with the rendering of select options

Ways to create a shorter upper line compared to the lower line (inside a div)

Using a factory function within a Typescript declaration file, both with and without the utilization of the new keyword

Guide to successfully finish $.get() after submitting a form with jQuery