Angularjs - Fetch object in ng-repeat - javascript

I have 2 separate json objects coming from the server. Json A below is of a Car model object which is fetch when looking at a car. Json B is meta data which is used throughout the whole application when the web page first loads.
What I need to do is have a lookup on wheel_id while doing a ng-repeat on wheel_handlers so it returns the wheel object from json B and then I can use this within the view and print the results. I think I need to do something with the ng-repeat but I'm not sure to be honest.
A - Car model
[{
id: 14,
name: "Audi",
wheel_handlers: [
{
id: 9,
wheel_id: 62,
arguments: {
amount: 10
}
}
]
}]
B - wheel
{
id: 62,
name: "Change Wheel Size",
arguments: [
{
id: 25,
description: "amount"
}
]
}

I am assuming the following: The Json "A" may include several cars, but also several wheel_handlers (because there is an array at wheel_handler). So the JSON for the cars may also look like this:
[
{
id: 14,
name: "Audi",
wheel_handlers: [
{
id: 9,
wheel_id: 62,
arguments: {
amount: 10
}
},
{
id: 12,
wheel_id: 65,
arguments: {
amount: 12
}
},
{
id: 15,
wheel_id: 30,
arguments: {
amount: 8
}
}
]
},
{
id: 16,
name: "Mercedes",
wheel_handlers: [
{
id: 9,
wheel_id: 62,
arguments: {
amount: 10
}
},
{
id: 12,
wheel_id: 65,
arguments: {
amount: 12
}
}
]
}
]
For the JSON file B I assume that you also meant an Array, which could contain several wheel definitions. As an example:
[
{
id: 62,
name: "Change Wheel Size",
arguments: [
{
id: 25,
description: "amount"
}
]
},
{
id: 65,
name: "test wheel",
arguments: [
{
id: 25,
description: "amount"
}
]
},
{
id: 30,
name: "another wheel",
arguments: [
{
id: 25,
description: "amount"
}
]
}
]
If this is the case, you could iterate over the cars and while iterating call a helper function in the AngularJS controller. You call this helper function and give wheel_handlers of the current car as a parameter. This helper function then checks the wheel_id of each wheel_handler entry and searches these ids in the JSON b file - the wheel definitions. The helper function returns an array containing the wheels, so in the view you may iterate over the wheels. This will use a nested ng-repeat, because at first you iterate over the cars and while iterating over the cars you will iterate over the wheels.
Here is an example of the controller part. I used $scope.cars as the JSON A, and $scope.wheels as JSON B.
var testApp = angular.module('testApp', []);
testApp.controller('testContr', function ($scope) {
$scope.cars = [];
$scope.wheels = [];
$scope.getWheelsByIds = function (wheel_handlers) {
var wheelIds = [];
var returnArray = [];
for (var wheelKey in wheel_handlers) {
wheelIds.push(wheel_handlers[wheelKey].wheel_id);
}
for (var key in $scope.wheels) {
console.log(wheelIds.indexOf($scope.wheels[key].id));
if (wheelIds.indexOf($scope.wheels[key].id) > -1) {
returnArray.push($scope.wheels[key]);
}
}
return returnArray;
}
});
The necessary HTML part could look like this:
<div ng-app="testApp" ng-controller="testContr">
<div ng-repeat="car in cars" ng-init="wheels = getWheelsByIds(car.wheel_handlers)">
<span>Car name: {{car.name}}</span><br/>
<div ng-repeat="wheel in wheels">
<span>Wheel name: {{wheel.name}}</span><br/>
</div>
<br/>
<br/>
</div>
</div>
I create a fiddle demonstration with the test data, view it here: http://jsfiddle.net/4F3YD/10/

You can nest ng-repeats like that, although I'm not sure what you want to achieve
following code will repeat through cars, then wheels in cars and display wheels from object B(wheels) that match the car wheel id, hope that makes sense
<div ng-repeat="car in CarModels">
<div ng-repeat="wheel in car.wheel_handlers">
{{Wheels | filter:wheel.wheel_id}}
</div>
</div>

You can make use of angular filter over here. In the filter function you can check for the id in the second json.
More Documentation on Angular Filter
Code Example:
<div ng-repeat="element in wheel | filterIds:element.id">
And filter Function:
.filter('filterIds', function () {
return function(id) {
$scope.carModel.forEach(function(car){
if(id == car.id)
return id;
});
}
})

Related

Functional Programming exercise I can't figure out

I've been looking at a problem for hours and failing to find a solution. I'm given an array of customer objects.
In each customer object is an array of friends.
In the array of friends is an object for each friend, containing some data, including a name key/value pair.
What I'm trying to solve for: I'm given this customers array and a customer's name. I need to create a function to find if this customer name is in any other customer's friend lists, and if so, return an array of those customer's names.
Below is a customer list. And as an example, one of the customers is Olga Newton. What the code should be doing is seeing that Olga Newton is a customer and is also in the friends lists of Regina and Jay, and should be returning an array of Regina and Jay.
I thought I could do this simply with a filter function, but because the friends list is an array with more objects, this is adding level of complexity for me I can't figure out.
Below is a customer array. The out put should be
['Regina', 'Jay']
and what I've gotten has either been
[{fullCustomerObj1}, {fullCustomerObj2}]
or
[ ]
What am I missing?
Here is the customer array:
var customers = [{
name: "Olga Newton",
age: 43,
balance: "$3,400",
friends: [{
id: 0,
name: "Justice Lara"
}, {
id: 1,
name: "Duke Patrick"
}, {
id: 2,
name: "Herring Hull"
}, {
id: 3,
name: "Johnnie Berg"
}]
}, {
name: "Regina",
age: 53,
balance: "$4,000",
friends: [{
id: 0,
name: "Cheryl Kent"
}, {
id: 1,
name: "Cynthia Wells"
}, {
id: 2,
name: "Gutierrez Waters"
}, {
id: 3,
name: "Olga Newton"
}]
}, {
name: "Jay",
age: 28,
balance: "$3,000",
friends: [{
id: 0,
name: "Cross Barnett"
}, {
id: 1,
name: "Raquel Haney"
}, {
id: 2,
name: "Olga Newton"
}, {
id: 3,
name: "Shelly Walton"
}]
}];
Use filter and map, please.
function friends(c, name){
return c.filter((a) => {
return a.friends.map(b => b.name).includes(name)
}).map(a => a.name);
}
console.log(friends(customers, "Olga Newton"));
// ['Regina', 'Jay']
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter
We look to an array (friends[]) inside anther (customers[]), So used two for loops, the first determine witch customer will look for his friends, and the second the array will search inside, then set if statement if the cust name is inside friends[]: adding the customer name to customerFriends[] array, At the end return the customerFriends[].
let cust = "Olga Newton"; // Get the customer name who you look for his friends.
const findFriend = (cust, arrs) => { // Create findFriend function.
let customerFriends = []; // Create an array to set the result to it.
for (let i = 0; i < arrs.length; i++) { // For each Customer.
for (const arr of arrs[i].friends) { // For each Friend.
if (arr.name === cust) { // Use Strict equality to find Customer name in friends[].
customerFriends.push(arrs[i].name); // Add the customer name to the customerFriends[].
}
}
}
return customerFriends;// Return the final results.
}
console.log(findFriend(cust, customers)); // Call the function.

Find and update value in array of nested objects

I have an object array as follows:
products = [
{
id: 1,
title: "Product 1",
specifications: {
price: 1.55,
discount: 15,
attributes: [
{
l1: 100,
l2: 80
height:200,
weight: 15,
parameters: [
{
id: 199199 // this is how I identify the parameter
size: 185 // this is what I want to change
}, ...
]
}, ...
]
}
}, ...
]
... and an array of changes to parameters I want to apply, for example: change size to 189 where product.specifications.attributes.parameters.id == 199199.
I'd like to do this without flattening any elements as they are part of a Vue.js data structure, it will break the reactivity.
How could I do this? I am open to using Underscore or lo-dash
This looks ugly, but it is effective:
To make it more dynamic, let's use variables: identifier will be your '199199' value and new_size for the '189' value.
methods: {
updateRecord: function(identifier, new_size) {
this.products.map(function(product) {
product.specifications.attributes.map(function(attribute) {
attribute.parameters.map(function(parameter) {
if (parameter.id == identifier) parameter.size = new_size;
})
});
});
}
}
Here is a working fiddle: https://jsfiddle.net/crabbly/eL7et9e8/
_.forEach(products, function(product) {
_.forEach(_.get(product, 'specifications.attributes', []), function(attribute) {
_.set(_.find(attribute.parameters, {id: 199199}), 'size', 189);
});
});
I believe what you want is underscore's findIndex() - http://underscorejs.org/#findIndex. Once you find which element in the array you want to apply the changes to (comparing the nested id to what you are looking for) you can then make the change to that particular element.

(javascript) Is it possible to split an array of different object types into multiple arrays of one object type

So I have an array that contains objects with different attributes and I want to know how I can make multiple arrays with objects with the same attributes of the whole array.
I want to go from this
[
{name:”test”, place:”country”},
{name:”walkAndEat”, Long=100,Lat:15,Location:”place name”},
{name:”test2”,place:”Europe”}
]
To
[
{name:”test”, place:”country”},
{name:”test2”,place:”Europe”}
]
[
{name:”walkAndEat”, Long:100,Lat:15,Location:”place name”}
]
If you see objects being equal as having the same properties, you can keep the keys as (stringified) indices in a collection object and check if a properties-key already exists:
var arrcoll = {};
function add(o){
var keys = JSON.stringify(Object.keys(o).sort());
var arr = arrcoll[keys];
if(arr)
arr.push(o);
else
arrcoll[keys] = [o];
return arr;
}
This can be done on the fly or on a pre existing array as shown in this Fiddle
Suppose you have a list of objects that have different properties like so:
var placesOrPeople = [
{ name: 'Seymour Skinner', occupation: 'Principal' },
{ name: 'Kwik-E-Mart', lat: 23, long: 100 },
{ name: 'Sideshow Bob', occupation: 'Comic Foil' },
{ name: 'Flaming Tyre Yard', lat: 12, long: 88 },
{ name: 'Joe Quimby', occupation: 'Mayor' }
];
And you want them sorted into separate lists like so:
places = [
{ name: 'Kwik-E-Mart', lat: 23, long: 100 },
{ name: 'Flaming Tyre Yard', lat: 12, long: 88 }
];
people = [
{ name: 'Seymour Skinner', occupation: 'Principal' },
{ name: 'Sideshow Bob', occupation: 'Comic Foil' },
{ name: 'Joe Quimby', occupation: 'Mayor' }
];
You can use the built-in Array.filter command like so:
var places = placesOrPeople.filter(function(currentPlaceOrPerson) {
if (currentPlaceOrPerson.occupation !== undefined) {
// it must be a person, since locations don't have occupations
return true;
} else {
return false;
}
});
var people = placesOrPeople.filter(function(currentPlaceOrPerson) {
if (currentPlaceOrPerson.lat !== undefined && currentPlaceOrPerson.long !== undefined) {
// it must be a place, since people don't have co-ordinates
return true;
} else {
return false;
}
});
Javascript Objects are not set types, they are dynamic, meaning you can change them during execution.
JavaScript is a loosely typed or a dynamic language. That means you don't have to declare the type of a variable ahead of time. The type will get determined automatically while the program is being processed. That also means that you can have the same variable as different types:
var anything = arrayOfAnyOtherType[0];
is valid... If you loop your source array and populate it, you can define any behavior to each object

How to merge two arrays into one array in angularjs?

This is my code
$scope.studentDetails=[];
$scope.studentDetails=[0][id:101,name:one]
[1][id:102,name:two]
[2][id:103,name:three]
$scope.studentMarks=[];
$scope.studentMarks=[0][id:101,marks:78]
[1][id:102,marks:89]
i have two arrays,first array contains 2 properties like id and name, second array contains two properties like id and marks,i want to concatinate these two arrays into one array.i want to get output like
$scope.studentDetails=[0][id:101,name:one,marks:78]
[1][id:102,name:two,marks:89]
[2][id:103,name:three,marks:null]
Lodash zip() should do that provided your JavaScript is valid in the first place.
$scope.studentDetails = _.zip($scope.studentDetails, $scope.studentMarks);
I got the answer
var newArray = [];
_.each($scope.studentDetails,function(obj))
{
var data=_.findWhere($scope.studentMarks,{"id":obj.id});
if(!_.isUndefined(data))
{
newArray.push({id:obj.id,name:obj.name,marks:data.marks});
}
else
{
newArray.push({id:obj.id,name:obj.name,marks:"null"});
}
}
Hey you can use the push like
$scope.studentDetails.push({'id':'101','name':'one','marks':'78'});
$scope.studentDetails.push({'id':'102','name':'two','marks':'78'});
$scope.studentDetails.push({'id':'103','name':'three','marks':'78'});
using loop you can append like bellow
for(i = 0; i < studentResult.length; i++){
$scope.studentDetails.push(studentResult[i]);
}
For object array _.zip merged two array into single array where each array element also an array.
You can use .map and .extend to create merged object array with _.zip like
var studentDetails = [{ id: 101, name: 'one' }, { id: 102, name: 'two' }, { id: 103, name: 'three' }];
var studentMarks = [{ id: 101, marks: 78 }, { id: 102, marks: 89 }];
var mergedArray = _.zip(studentDetails, studentMarks); //where each element also an array like [ [{ id: 101, name: 'one' }, { id: 101, marks: 78 }] ]
var studentDetails = _.map(mergedArray, function (item) { return _.extend(item[0], item[1]); }); //[{ id: 101, marks: 78, name: 'one' }, ..]

init javascript object with array property with child objects

Is there a way to initialize a javascript object with an array of child objects in one line? How can I do the following in just on initialization line.
var obj = {doc: 100,
defaultrateid: 32,
rates: [],
};
obj.rates[31] = {rate: 101.00, name: "Rate 1"};
obj.rates[32] = {rate: 121.00, name: "Rate 2"};
Basically what I want is a single javascript object that has my user parameters. This object will be reused on multiple web forms. In the case of 'rates', the forms will have a dropdown to select a rate. The web forms have client side calculations that require the matching rate object based on the rate's unique id (e.g. 32).
I'm trying to use a associative array instead of having to do looping for finding a match based on unique value.
Seems a bit hacky:
obj = {
doc: 100,
defaultrateid: 32,
rates: (new Array(30)).concat([{
rate: 101.00,
name: "Rate 1"
}, {
rate: 121.00,
name: "Rate 2"
}])
};
EDIT:
Maybe you don't really need an array, you can use an object like this:
obj = {
doc: 100,
defaultrateid: 32,
rates: {
"31": {
rate: 101.00,
name: "Rate 1"
},
"32": {
rate: 121.00,
name: "Rate 2"
}
}
};
And you can still get the rates like obj.rates[31].
Do you mean like this?
var obj = {
doc: 100,
defaultrateid: 32,
rates: [{
rate: 101.00
}, {
rate: 121.00
}],
};
alert(obj.rates[1].rate);

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