I have very little javascript experience. I need to add a menu on click of an item. We have been asked to build it from scratch without using any library like bootstrap compoments or JQuery.
We are using Angularjs. In angular I want to know the correct method to create new elements. Something like what we did not document.createElement.
I am adding some of the code for you guys to have a better idea what I want to do.
Menu Directive
.directive('menu', ["$location","menuData", function factory(location, menuData) {
return {
templateUrl: "partials/menu.html",
controller: function ($scope, $location, $document) {
$scope.init = function (menu) {
console.log("init() called");
console.log("$document: " + $document);
if (menu.selected) {
$scope.tabSelected(menu);
}
}
$scope.creteMenu = function(menuContent){
//This is to be called when the action is an array.
}
$scope.tabSelected = function(menu){
$location.url(menu.action);
$scope.selected = menu;
}
$scope.click = function (menu) {
if (typeof (menu.action) == 'string') {
$scope.tabSelected(menu);
}
}
},
link: function (scope, element, attrs) {
scope.menuData = menuData;
}
};
}])
Menu data in service.
.value('menuData', [{ label: 'Process-IDC', action: [] }, { label: 'Dash Board', action: '/dashboard', selected: true }, { label: 'All Jobs', action: '/alljobs', selected: false }, { label: 'My Jobs', action: '/myjobs', selected: false }, { label: 'Admin', action: '/admin', selected: false }, { label: 'Reports', action: '/reports', selected: false }]);
If you notice the action of Process-IDC menu is an array it will contain more menu with actions in it and it should be opened in a sub menu.
Menu.html (partial)
<ul class="menu">
<li ng-class="{activeMenu: menu==selected}" ng-init="init(menu)" data-ng-click="click(menu)" data-ng-repeat="menu in menuData">{{menu.label}}</li>
</ul>
A few things come to mind. First of all, are you sure you need to actually create the element on click? If you are doing to to show a fixed element on click then the better approach would be to generate the element as normal, but not show it until you click. Something like:
<div ng-click="show_it=true">Show item</div>
<div ng-show="show_it">Hidden until the click. Can contain {{dynamic}} content as normal.</div>
If you need it to be dynamic because you might add several elements, and you don't know how many, you should look at using a repeat and pushing elements into a list. Something like this:
<div ng-click="array_of_items.push({'country': 'Sparta'})">Add item</div>
<div ng-repeat="item in array_of_items"> This is {{item.country}}</div>
Each click of the "Add item" text here will create another div with the text "This is Sparta". You can push as complex an item as you want, and you could push an item directly from the scope so you don't have to define it in the template.
<div ng-click="functionInControllerThatPushesToArray()">Add item</div>
<div ng-repeat="item in array_of_items"> This is {{item.country}}</div>
If neither of those options would work because it is a truly dynamic object, then I would start looking at using a directive for it like others have suggested (also look at $compile). But from what you said in the question I think a directive would be to complicate things needlessly.
I recommend you read the ngDirective and the angular.element docs.
Hint: angular.element has an append() method.
This is both really simple, but some what complex if you don't know where to start - I really recommend looking at the Tutorial, and following it end to end: http://docs.angularjs.org/tutorial/ - As that will introduce you to all the concepts around Angular which will help you understand the technical terms used to describe the solution.
If you're creating whole new menu items, if in your controller your menu is something like:
// An Array of Menu Items
$scope.menuItems = [{name: 'Item One',link: '/one'},{name: 'Item Two',link:'/two'}];
// Add a new link to the Array
$scope.addMenuItem = function(theName,theLink){
$scope.menuItems.push({name: theName,link:theLink});
}
And in the template, use the array inside ng-repeat to create the menu:
<ul>
<li ng-repeat="menuItem in menuItems">{{menuItem.name}}</li>
</ul>
If you just want to toggle the display of an item that might be hidden, you can use ng-if or ng-show
Assuming that you are doing it in a directive and you have angular dom element, you can do
element.append("<div>Your child element html </div>");
We can use $scope in App Controller to create Div Elements and then we can append other Div elements into it similarly.
Here's an Example:
$scope.div = document.createElement("div");
$scope.div.id = "book1";
$scope.div.class = "book_product";
//<div id="book1_name" class="name"> </div>
$scope.name = document.createElement("div");
$scope.name.id = "book1_name";
$scope.name.class= "name";
// $scope.name.data="twilight";
$scope.name.data = $scope.book.name;
$scope.div.append($scope.name);
console.log($scope.name);
//<div id="book1_category" class="name"> </div>
$scope.category = document.createElement("div");
$scope.category.id = "book1_category";
$scope.category.class= "category";
// $scope.category.data="Movies";
$scope.category.data=$scope.book.category;
$scope.div.append($scope.category);
console.log("book1 category = " + $scope.category.data);
//<div id="book1_price" class="price"> </div>
$scope.price = document.createElement("div");
$scope.price.id = "book1_price";
$scope.price.class= "price";
// $scope.price.data=38;
$scope.price.data=$scope.book.price;
$scope.div.append($scope.price);
console.log("book1 price = " + $scope.price.data);
//<div id="book1_author" class="author"> </div>
$scope.author = document.createElement("div");
$scope.author.id = "book1_author";
$scope.author.class= "author";
// $scope.author.data="mr.book1 author";
$scope.author.data=$scope.book.author;
$scope.div.append($scope.author);
console.log("book1 author = " + $scope.author.data);
//adding the most outer Div to document body.
angular.element(document.getElementsByTagName('body')).append($scope.div);
For more illustration, Here each book has some attributes (name, category, price and author) and book1 is the most outer Div Element and has it's attributes as inner Div elements.
Created HTML element will be something like that
Related
I would like to use a javascript loop to create multiple HTML wrapper elements and insert JSON response API data into some of the elements (image, title, url, etc...).
Is this something I need to go line-by-line with?
<a class="scoreboard-video-outer-link" href="">
<div class="scoreboard-video--wrapper">
<div class="scoreboard-video--thumbnail">
<img src="http://via.placeholder.com/350x150">
</div>
<div class="scoreboard-video--info">
<div class="scoreboard-video--title">Pelicans # Bulls Postgame: E'Twaun Moore 10-8-17</div>
</div>
</div>
</a>
What I am trying:
var link = document.createElement('a');
document.getElementsByTagName("a")[0].setAttribute("class", "scoreboard-video-outer-link");
document.getElementsByTagName("a")[0].setAttribute("url", "google.com");
mainWrapper.appendChild(link);
var videoWrapper= document.createElement('div');
document.getElementsByTagName("div")[0].setAttribute("class", "scoreboard-video-outer-link");
link.appendChild(videoWrapper);
var videoThumbnailWrapper = document.createElement('div');
document.getElementsByTagName("div")[0].setAttribute("class", "scoreboard-video--thumbnail");
videoWrapper.appendChild(videoThumbnailWrapper);
var videoImage = document.createElement('img');
document.getElementsByTagName("img")[0].setAttribute("src", "url-of-image-from-api");
videoThumbnailWrapper.appendChild(videoImage);
Then I basically repeat that process for all nested HTML elements.
Create A-tag
Create class and href attributes for A-tag
Append class name and url to attributes
Append A-tag to main wrapper
Create DIV
Create class attributes for DIV
Append DIV to newly appended A-tag
I'd greatly appreciate it if you could enlighten me on the best way to do what I'm trying to explain here? Seems like it would get very messy.
Here's my answer. It's notated. In order to see the effects in the snippet you'll have to go into your developers console to either inspect the wrapper element or look at your developers console log.
We basically create some helper methods to easily create elements and append them to the DOM - it's really not as hard as it seems. This should also leave you in an easy place to append JSON retrieved Objects as properties to your elements!
Here's a Basic Version to give you the gist of what's happening and how to use it
//create element function
function create(tagName, props) {
return Object.assign(document.createElement(tagName), (props || {}));
}
//append child function
function ac(p, c) {
if (c) p.appendChild(c);
return p;
}
//example:
//get wrapper div
let mainWrapper = document.getElementById("mainWrapper");
//create link and div
let link = create("a", { href:"google.com" });
let div = create("div", { id: "myDiv" });
//add link as a child to div, add the result to mainWrapper
ac(mainWrapper, ac(div, link));
//create element function
function create(tagName, props) {
return Object.assign(document.createElement(tagName), (props || {}));
}
//append child function
function ac(p, c) {
if (c) p.appendChild(c);
return p;
}
//example:
//get wrapper div
let mainWrapper = document.getElementById("mainWrapper");
//create link and div
let link = create("a", { href:"google.com", textContent: "this text is a Link in the div" });
let div = create("div", { id: "myDiv", textContent: "this text is in the div! " });
//add link as a child to div, add the result to mainWrapper
ac(mainWrapper, ac(div, link));
div {
border: 3px solid black;
padding: 5px;
}
<div id="mainWrapper"></div>
Here is how to do specifically what you asked with more thoroughly notated code.
//get main wrapper
let mainWrapper = document.getElementById("mainWrapper");
//make a function to easily create elements
//function takes a tagName and an optional object for property values
//using Object.assign we can make tailored elements quickly.
function create(tagName, props) {
return Object.assign(document.createElement(tagName), (props || {}));
}
//document.appendChild is great except
//it doesn't offer easy stackability
//The reason for this is that it always returns the appended child element
//we create a function that appends from Parent to Child
//and returns the compiled element(The Parent).
//Since we are ALWAYS returning the parent(regardles of if the child is specified)
//we can recursively call this function to great effect
//(you'll see this further down)
function ac(p, c) {
if (c) p.appendChild(c);
return p;
}
//these are the elements you wanted to append
//notice how easy it is to make them!
//FYI when adding classes directly to an HTMLElement
//the property to assign a value to is className -- NOT class
//this is a common mistake, so no big deal!
var link = create("a", {
className: "scoreboard-video-outer-link",
url: "google.com"
});
var videoWrapper = create("div", {
className: "scoreboard-video-outer-link"
});
var videoThumbnailWrapper = create("div", {
className: "scoreboard-video--thumbnail"
});
var videoImage = create("img", {
src: "url-of-image-from-api"
});
//here's where the recursion comes in:
ac(mainWrapper, ac(link, ac(videoWrapper, ac(videoThumbnailWrapper, videoImage))));
//keep in mind that it might be easiest to read the ac functions backwards
//the logic is this:
//Append videoImage to videoThumbnailWrapper
//Append (videoImage+videoThumbnailWrapper) to videoWrapper
//Append (videoWrapper+videoImage+videoThumbnailWrapper) to link
//Append (link+videoWrapper+videoImage+videoThumbnailWrapper) to mainWrapper
let mainWrapper = document.getElementById('mainWrapper');
function create(tagName, props) {
return Object.assign(document.createElement(tagName), (props || {}));
}
function ac(p, c) {
if (c) p.appendChild(c);
return p;
}
var link = create("a", {
className: "scoreboard-video-outer-link",
url: "google.com"
});
var videoWrapper = create("div", {
className: "scoreboard-video-outer-link"
});
var videoThumbnailWrapper = create("div", {
className: "scoreboard-video--thumbnail"
});
var videoImage = create("img", {
src: "url-of-image-from-api"
});
ac(mainWrapper, ac(link, ac(videoWrapper, ac(videoThumbnailWrapper, videoImage))));
//pretty fancy.
//This is just to show the output in the log,
//feel free to just open up the developer console and look at the mainWrapper element.
console.dir(mainWrapper);
<div id="mainWrapper"></div>
Short version
Markup.js's loops.
Long version
You will find many solutions that work for this problem. But that may not be the point. The point is: is it right? And you may using the wrong tool for the problem.
I've worked with code that did similar things. I did not write it, but I had to work with it. You'll find that code like that quickly becomes very difficult to manage. You may think: "Oh, but I know what it's supposed to do. Once it's done, I won't change it."
Code falls into two categories:
Code you stop using and you therefore don't need to change.
Code you keep using and therefore that you will need to change.
So, "does it work?" is not the right question. There are many questions, but some of them are: "Will I be able to maintain this? Is it easy to read? If I change one part, does it only change the part I need to change or does it also change something else I don't mean to change?"
What I'm getting at here is that you should use a templating library. There are many for JavaScript.
In general, you should use a whole JavaScript application framework. There are three main ones nowadays:
ReactJS
Vue.js
Angular 2
For the sake of honesty, note I don't follow my own advice and still use Angular. (The original, not Angular 2.) But this is a steep learning curve. There are a lot of libraries that also include templating abilities.
But you've obviously got a whole project already set up and you want to just plug in a template into existing JavaScript code. You probably want a template language that does its thing and stays out of the way. When I started, I wanted that too. I used Markup.js . It's small, it's simple and it does what you want in this post.
https://github.com/adammark/Markup.js/
It's a first step. I think its loops feature are what you need. Start with that and work your way to a full framework in time.
Take a look at this - [underscore._template]
It is very tiny, and useful in this situation.
(https://www.npmjs.com/package/underscore.template).
const targetElement = document.querySelector('#target')
// Define your template
const template = UnderscoreTemplate(
'<a class="<%- link.className %>" href="<%- link.url %>">\
<div class="<%- wrapper.className %>">\
<div class="<%- thumbnail.className %>">\
<img src="<%- thumbnail.image %>">\
</div>\
<div class="<%- info.className %>">\
<div class="<%- info.title.className %>"><%- info.title.text %></div>\
</div>\
</div>\
</a>');
// Define values for template
const obj = {
link: {
className: 'scoreboard-video-outer-link',
url: '#someurl'
},
wrapper: {
className: 'scoreboard-video--wrapper'
},
thumbnail: {
className: 'scoreboard-video--thumbnail',
image: 'http://via.placeholder.com/350x150'
},
info: {
className: 'scoreboard-video--info',
title: {
className: 'scoreboard-video--title',
text: 'Pelicans # Bulls Postgame: E`Twaun Moore 10-8-17'
}
}
};
// Build template, and set innerHTML to output element.
targetElement.innerHTML = template(obj)
// And of course you can go into forEach loop here like
const arr = [obj, obj, obj]; // Create array from our object
arr.forEach(item => targetElement.innerHTML += template(item))
<script src="https://unpkg.com/underscore.template#0.1.7/dist/underscore.template.js"></script>
<div id="target">qq</div>
I'm trying to toggle an open class on a list of items in a v-repeat. I only want one list item (the one most recently clicked) to have the class open.
The data being output has a "class" attribute which is a blank string by default. I'm using this to set the class of the list items in the v-repeat like so:
<li v-repeat="dataSet"
v-on="click: toggleFunction(this)"
class="{{ class }}">
{{ itemContent }}
</li>
I'm using v-on="click: toggleFunction(this)" on each item, which lets me change the class for the specific item, but how do I change the class on all the other items?
My current on-click method:
toggleFunction: function(item) {
if (item.class == '') {
// code to remove the `open` class from all other items should go here.
item.class = 'open';
} else {
item.class = '';
}
}
I've tried using a regular jQuery function to strip the classes: that does remove the classes but it doesn't change the item.class attribute, so things get weird once an item gets clicked more than once...
I'm sure there must be a straightforward way to fix this that I'm not seeing, and having to set a class attribute in the data itself feels hacky anyway (but I'll settle for any fix that works).
I just ran into the same issue. I am still learning Vue, but I tackled it using the "v-class" directive. Using v-class, any time an active value is true for a record, it will automatically add the class "open" to the list element. Hope this JSFiddle helps.
<ul>
<li
v-repeat="people"
v-on="click: toggleActive(this)"
v-class="open: active">{{ name }}
</li>
</ul>
new Vue({
el: '#app',
data: {
people: [
{name: 'mike'},
{name: 'joe',active: true},
{name: 'tom'},
{name: 'mary'}
]
},
methods: {
toggleActive: function(person) {
// remove active from all people
this.people.forEach(function(person){
person.$set('active',false);
});
//set active to clicked person
person.$set('active',true);
}
}
});
In my angular application I have several panels which have a shared structure, identical html.
Inside the panel the content and behavior changes, basically each one is a separate directive, let's call them panel-content.
This is the close to the solution I think is optimal but I have some architectural doubts.
Since I have directive (which has transclude true set):
<panel></panel>
It's template looks like this:
<div>
Content
<ng-transclude></ng-transclude>
</div>
I have to repeat the panels
<ul>
<li ng-repeat="panel in panels">
<panel>
<panel-content></panel-content>
</panel>
</li>
</ul
This is all fine, but what would be a reasonably good way of "choosing" on each iteration which <panel-content> should I show?
Lets say I have a panel.id I can use.
I notice I can achieve it in several ways, I could do an ng-switch inside the <panel-content> view using the panel id, I could set up that the templateUrl of has a dynamic part and links to different URLs depending on the panel.id.
But for some reason, I am convinced I am missing something nicer more straightforward?
Please not that this architecture is not set in stone, if there is another structure that would better fit my needs please let me know.
So, the question again is, how do I choose? Or rather, who is responsible for choosing which <panel-content> should be displayed.
If I understand you right, I would use ng-include in directive that changes each time the template by id:
Something like:
<ul>
<li ng-repeat="panel in panels">
<panel type-id="panel.id">
</panel>
</li>
</ul>
and Directive:
app.directive('panel',
function() {
return {
restrict: 'E',
replace: true,
template: '<ng-include src="getTemplateUrl()"/>',
link: function(scope,elem,attrs) {
scope.getTemplateUrl = function() {
var url;
if(attrs.typeId !== undefined){
var url = $rootScope.list_templates[attrs.typeId].value; // TODO: add validation
}
return url;
};
}
});
app
$rootScope.list_templates = [
{ id: 0, value: 'partials/upcoming_0.html'},
{ id: 1, value: 'partials/upcoming_1.html'},
{ id: 2, value: 'partials/upcoming_2.html'}
];
I am trying to add a class to a clicked element and remove it when user clicks other elements.
I have something like
<li ng-repeat='test in tests' >
<a href='' ng-click='pickTest($index, $event)'>{{test.title}}</a>
</li>
js
$scope.pickTest = function(index, event) {
$(event.target).addClass('blur');
//this works when user clicks one of the <a> tags
//but I want to remove the class if user clicks another <a> tag
};
How do I do this?
Thanks!
You can use ng-class to determine if the class needs to be appended based on a certain condition. Additionally, using $index in an ng-repeat is really not advisable because it pose problems when filters are applied in the ng-repeat directive. You can create two functions, isActive() for the ng-class directive and setActive() to set the active item.
angular.module('app', [])
.controller('Ctrl', function($scope) {
var activeTest = {};
$scope.tests = [{
title: 'Test 1'
}, {
title: 'Test 2'
}, {
title: 'Test 3'
}, {
title: 'Test 4'
}];
$scope.setActive = function(test) {
activeTest = test;
};
$scope.isActive = function(test) {
return angular.equals(activeTest, test);
};
});
.blur {
color: red;
}
<div ng-app="app" ng-controller="Ctrl">
<ul>
<li ng-repeat="test in tests">
{{test.title}}
</li>
</ul>
</div>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
Use ng-class, like this:
<li ng-repeat='test in tests' >
<a ng-class={blur:blurActive} href='' ng-click='pickTest($index, $event);blurActive=true'>{{test.title}}</a>
</li>
Notice that you don't need to set blurActive to true inside your function, because ng-repeat creates a new scope for each "repeated item", so you can set it active inside the same ng-click, after you call your function, in this way the logic of your function won't be mixed with the design.
Doing DOM manipulation in a controller is considered bad practice, you could achieve this angular way using ng-class:-
<li ng-repeat="test in tests">
<a href="#" ng-click="pickTest($index, $event)"
ng-class="{'blur': opt.selectedIdx == $index}">{{test.title}}</a>
</li>
and in your controller, just do:-
$scope.opt = {}; //Set an initial value in your controller
$scope.pickTest = function(index, $event) {
$event.preventDefault(); //If you need
$scope.opt.selectedIdx = index ; //Set the current index here, You could do this inline as well in the html, but probably better off having logic in your controller
}
Plnkr
Just select all other elements with the class blur and remove the class from them before you assign the class to the currently clicked element.
$scope.pickTest = function(index, event) {
$('.blur').removeClass('blur');
$(event.target).addClass('blur');
};
I'm trying to create a menu bar using Angularjs. I've done similar things before with Backbonejs, but I have a hard time getting my head around how to do this with angular.
In my html file, I have the following menu placeholder.
<div id='menu1'></div>
<div id='menu2'></div>
<div id='menu3'></div>
<div id='menu4'></div>
<div id='menu5'></div>
A number of my angular modules add a menu when they are loaded (in run). Each of them only reserves a particular slot (i.e. menu1..5), so they don't clash. When some modules aren't loaded, their menu would not show in the menu bar.
An angular module would conceptually look like:
angular.module('myModule3', [])
.service('someService', function($http) {
// get some data to populate menu (use $http)
this.menuItems = ['orange', 'apple', 'banana']
})
.run(['someService', function(someService) {
// create a rendered menu item
...
// insert it at id="menu3"
})
For sake of simplicity, the rendered menu item should look like:
<ul>
<li>organge</li>
<li>apple</li>
<li>banana</li>
</ul>
I'm fairly new to angular, so I don't really know where to begin. I've been reading up on directives, but don't see how they fit in here, as they require some custom markup (maybe a custom menu tag containing the DOM target (i.e. menu..5). Also, how to connect this to a controller is not clear to me.
Update
In addition to the above base template (containing arbitrary anchor points in the DOM) and the directive (which will produce a DOM element which will be inserted at these anchor points), a template will facilitate the creation of the DOM element. This template will be located in a separate file containing the position the directive's DOM element will be inserted to (as opposed to the usual case of directives in which an already existing tag will be replaced/inserted into specific markup that matches the directive's definition:
<menu ng-model="Model3DataService" target="#menu3">
<ul>
<li ng-repeat="for item in items"></li>
</ul>
</menu>
Again, coming from a Backbone/jquery background this makes sense, but this may not be the right thing to do in angular. If so, please let me know how I could keep the base template free of any knowledge about the modules and assumptions of where they put their menu (i.e. which slot of the menu bar they allocate). I'm happy to hear about other solutions...
Each module should have its menu loader defined:
angular.module('module1', []).
factory('module1.menuLoader', function() {
return function(callback) {
callback(['oranges', 'bananas'])
}
});
Your application should contain menu directive which can load menu items for any module only if exists.
angular.module('app', ['module1']).
directive('menu', ['$injector', function($injector) {
return {
restrict: 'A',
template:
'<ul><li ng-repeat="item in items">{{item}}</li></ul>',
scope: {},
link: function($scope, $element, $attrs) {
var menuLoaderName = $attrs.menu+'.menuLoader';
if ($injector.has(menuLoaderName)) {
var loaderFn = $injector.get(menuLoaderName);
loaderFn(function(menuItems) {
$scope.items = menuItems;
});
}
}
};
}]);
Final html:
<div class="content">
<div menu="module1"></div>
<div menu="module2"></div>
<div menu="module3"></div>
</div>
After running the application only module1 menu will be loaded. Other menu placeholders remain empty.
Live demo: http://plnkr.co/edit/4tZQGSkJToGCirQ1cmb6
Updated: If you want to generate markup on the module side the best way is to put the template to the $templateCache in the module where it's defined and then pass the templateName to the application.
angular.module('module1', []).
factory('module1.menuLoader', ['$templateCache', function($templateCache) {
$templateCache.put('module1Menu', '<ul><li ng-repeat="item in items">{{item}}</li></ul>');
return function(callback) {
callback('module1Menu', ['oranges', 'bananas'])
}
}]);
angular.module('app', ['module1'])
.directive('menu', ['$injector', function($injector) {
return {
restrict: 'A',
template:
'<div ng-include="menuTemplate"></div>',
scope: {},
link: function($scope, $element, $attrs) {
var menuLoaderName = $attrs.menu+'.menuLoader';
if ($injector.has(menuLoaderName)) {
var loaderFn = $injector.get(menuLoaderName);
loaderFn(function(menuTemplate, menuItems) {
$scope.menuTemplate = menuTemplate;
$scope.items = menuItems;
});
}
}
};
}]);