Dependent / Cascading Losses in Aurelia

Question

I would like to create dependent dropdowns in Aurelia.

What I mean by the dependent drop-down list is if you click an item in the first drop-down list, then the options in the second drop-down list will be filtered out depending on what you click. If you look at my js-violin, you will notice that if you select Toyota in the first drop-down list, the second will be filled with Toyota car models (Corolla, Camry, etc.). If you select Honda in the first drop-down menu, the second fills itself with Honda models (Accord, Civic, etc.). You get the idea.

It is very simple and requires very little code for this in Angular, and I was wondering if this makes this in Aurelia also simple and straightforward. I could not find much information on how to do this in Aurelia. The violin below demonstrates exactly what I would like to accomplish (except that I would like to do this in Aurelia, not Angular, of course). Any help is appreciated. Thank!

https://jsfiddle.net/nhunt3/wjvvjwzx/

HTML:

<div ng-app="myApp" ng-controller="myController">
My Cars
<br />
<table>
  <thead>
    <tr>
      <td>Make</td>
      <td>Model</td>
    </tr>
  </thead>

  <tbody>
    <tr ng-repeat="car in myCars track by car.uid">
      <td>
        <select ng-model="car.MakeUID" ng-options="make.uid as make.name for make in makes" />
      </td>

      <td>
        <select
        ng-model="car.ModelUID"
        ng-options="model.uid as model.name for model in models | filter: { parentID: car.MakeUID } : true" />
      </td>
    </tr>
  </tbody>
</table>   
</div>

JavaScript:

// the main (app) module
var myApp = angular.module("myApp", []);

angular.module('myApp', []).controller('myController', function($scope) {
    $scope.makes = [
        {name:'Toyota', uid:1},
        {name:'Honda', uid:2},
        {name:'Ford', uid:3}
    ];

  $scope.models = [
            {name:'Yaris', uid:1, parentID:1},
        {name:'Corolla', uid:2, parentID:1},
        {name:'Camry', uid:3, parentID:1},
        {name:'Highlander', uid:4, parentID:1},
        {name:'Accord', uid:5, parentID:2},
        {name:'Civic', uid:6, parentID:2},
        {name:'Pilot', uid:7, parentID:2},
        {name:'Focus', uid:8, parentID:3},
        {name:'Fiesta', uid:9, parentID:3},
        {name:'Fusion', uid:10, parentID:3},
        {name:'F-150', uid:10, parentID:3}
    ];

  $scope.myCars = [
        {uid:1, MakeUID:1, ModelUID:2},
        {uid:2, MakeUID:1, ModelUID:3},
        {uid:3, MakeUID:3, ModelUID:8}
    ];
});

Answer 1

For other users who are looking for this topic:

app.html

<template>
  <require from="./filter"></require>
  <table>
  <thead>
    <tr>
      <td>Make</td>
      <td>Model</td>
    </tr>
  </thead>
  <tbody>
    <tr repeat.for="car of myCars">
      <td>
        <select value.bind="car.MakeUID" change.delegate="resetModel(car)">
          <option value="0">select one of ...</option>
          <option repeat.for="make of makes" model.bind="make.uid">${make.name}</option>
        </select>
      </td>
      <td>
        <select value.bind="car.ModelUID">
          <option value="0">select one of ...</option>
          <option repeat.for="model of models | filter:'parentID':car.MakeUID" model.bind="model.uid">${model.name}</option>
        </select>
      </td>
    </tr> 
  </tbody>
</template>

app.js

export class App { 
    makes = [
        {name:'Toyota', uid:1},
        {name:'Honda', uid:2},
        {name:'Ford', uid:3}
    ];

    models = [
        {name:'Yaris', uid:1, parentID:1},
        {name:'Corolla', uid:2, parentID:1},
        {name:'Camry', uid:3, parentID:1},
        {name:'Highlander', uid:4, parentID:1},
        {name:'Accord', uid:5, parentID:2},
        {name:'Civic', uid:6, parentID:2},
        {name:'Pilot', uid:7, parentID:2},
        {name:'Focus', uid:8, parentID:3},
        {name:'Fiesta', uid:9, parentID:3},
        {name:'Fusion', uid:10, parentID:3},
        {name:'F-150', uid:10, parentID:3}
    ];

    myCars = [
        {uid:1, MakeUID:1, ModelUID:2},
        {uid:2, MakeUID:1, ModelUID:3},
        {uid:3, MakeUID:3, ModelUID:8}
    ];

    resetModel(car) {
      car.ModelUID = 0;
    }
}

filter.js

export class FilterValueConverter {
  toView(array, propertyName, filter_on) {
    return array.filter(i => i[propertyName] == filter_on);
  }
}

old answer

I think this does the same as your Angular code in Aurelia:

<template>
  <require from="./filter"></require>
  <table>
  <thead>
    <tr>
      <td>Make</td>
      <td>Model</td>
    </tr>
  </thead>
  <tbody>
    <tr repeat.for="car of myCars">
      <td>
        <select value.bind="car.MakeUID" ref="selected_car">
          <option repeat.for="make of makes" value.bind="make.uid">${make.name}</option>
        </select>
      </td>

      <td>
        <select value.bind="car.ModelUID">
          <option repeat.for="model of models | filter:'parentID':selected_car.value">${model.name}</option>
        </select>
      </td>
    </tr> 
  </tbody>
</template>

And you also need this filter:

export class FilterValueConverter {
  toView(array, propertyName, filter_on) {
    return array.filter(i => i[propertyName] == filter_on);
  }
}

https://gist.run/?id=91b23375e0b73afe7f21825f67cfeabf

Answer 2

, . ref make td model.binds .

. , .

https://gist.run/?id=e0b9c401370a954b594ad2415d983099