Develop Reference

KnockoutJs call function in other viewmodel of applyBindings

On a page I'm calling ko.applyBindings twice to iniate 2 view models. When viewModelOne saves successfully, I want to reload the other view model as some data is added in the backend as they are loosely linked.
Now I'm trying to call viewModelTwo.reloadData in saveSuccess() but I keep getting the error that it can't find the function whatever I try.
(Uncaught TypeError: viewModelTwo.reloadData is not a function)
What is the correct way of calling a function from the other viewmodel in KnockoutJs? Could anyone point me in the right direction?
var viewModelOne = (function () {
function reloadData(url) {
...
}
function saveSuccess(){
viewModelTwo.reloadData('');
}
});
var viewModelTwo = (function () {
function reloadData(url) {
...
}
});
ko.applyBindings(viewModelOne, document.getElementById("modelOneContainer"));
ko.applyBindings(viewModelTwo, document.getElementById("modelTwoContainer"));

You could use a constructor function:
function ViewModelOne() {
var vm = this;
vm.reloadData = function() {
console.log('vm1 reloaddata');
}
}
var vm1 = new ViewModelOne();
function ViewModelTwo() {
var vm = this;
vm.reloadData = function() {
vm1.reloadData();
console.log('vm2 reloaddata');
}
}
var vm2 = new ViewModelTwo();
ko.applyBindings(vm1, document.getElementById("modelOneContainer"));
ko.applyBindings(vm2, document.getElementById("modelTwoContainer"));
vm2.reloadData();
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.4.2/knockout-min.js"></script>
<div id="modelOneContainer"></div>
<div id="modelTwoContainer"></div>

jQuery plugin instances variable with event handlers

I am writing my first jQuery plugin which is a tree browser. It shall first show the top level elements and on click go deeper and show (depending on level) the children in a different way.
I got this up and running already. But now I want to implement a "back" functionality and for this I need to store an array of clicked elements for each instance of the tree browser (if multiple are on the page).
I know that I can put instance private variables with "this." in the plugin.
But if I assign an event handler of the onClick on a topic, how do I get this instance private variable? $(this) is referencing the clicked element at this moment.
Could please anyone give me an advise or a link to a tutorial how to get this done?
I only found tutorial for instance specific variables without event handlers involved.
Any help is appreciated.
Thanks in advance.
UPDATE: I cleaned out the huge code generation and kept the logical structure. This is my code:
(function ($) {
$.fn.myTreeBrowser = function (options) {
clickedElements = [];
var defaults = {
textColor: "#000",
backgroundColor: "#fff",
fontSize: "1em",
titleAttribute: "Title",
idAttribute: "Id",
parentIdAttribute: "ParentId",
levelAttribute: "Level",
treeData: {}
};
var opts = $.extend({}, $.fn.myTreeBrowser.defaults, options);
function getTreeData(id) {
if (opts.data) {
$.ajax(opts.data, { async: false, data: { Id: id } }).success(function (resultdata) {
opts.treeData = resultdata;
});
}
}
function onClick() {
var id = $(this).attr('data-id');
var parentContainer = getParentContainer($(this));
handleOnClick(parentContainer, id);
}
function handleOnClick(parentContainer, id) {
if (opts.onTopicClicked) {
opts.onTopicClicked(id);
}
clickedElements.push(id);
if (id) {
var clickedElement = $.grep(opts.treeData, function (n, i) { return n[opts.idAttribute] === id })[0];
switch (clickedElement[opts.levelAttribute]) {
case 1:
renderLevel2(parentContainer, clickedElement);
break;
case 3:
renderLevel3(parentContainer, clickedElement);
break;
default:
debug('invalid level element clicked');
}
} else {
renderTopLevel(parentContainer);
}
}
function getParentContainer(elem) {
return $(elem).parents('div.myBrowserContainer').parents()[0];
}
function onBackButtonClick() {
clickedElements.pop(); // remove actual element to get the one before
var lastClickedId = clickedElements.pop();
var parentContainer = getParentContainer($(this));
handleOnClick(parentContainer, lastClickedId);
}
function renderLevel2(parentContainer, selectedElement) {
$(parentContainer).html('');
var browsercontainer = $('<div>').addClass('myBrowserContainer').appendTo(parentContainer);
//... rendering the div ...
// for example like this with a onClick handler
var div = $('<div>').attr('data-id', element[opts.idAttribute]).addClass('fct-bs-col-md-4 pexSubtopic').on('click', onClick).appendTo(subtopicList);
// ... rendering the tree
var backButton = $('<button>').addClass('btn btn-default').text('Back').appendTo(browsercontainer);
backButton.on('click', onBackButtonClick);
}
function renderLevel3(parentContainer, selectedElement) {
$(parentContainer).html('');
var browsercontainer = $('<div>').addClass('myBrowserContainer').appendTo(parentContainer);
//... rendering the div ...
// for example like this with a onClick handler
var div = $('<div>').attr('data-id', element[opts.idAttribute]).addClass('fct-bs-col-md-4 pexSubtopic').on('click', onClick).appendTo(subtopicList);
// ... rendering the tree
var backButton = $('<button>').addClass('btn btn-default').text('Back').appendTo(browsercontainer);
backButton.on('click', onBackButtonClick);
}
function renderTopLevel(parentContainer) {
parentContainer.html('');
var browsercontainer = $('<div>').addClass('fct-page-pa fct-bs-container-fluid pexPAs myBrowserContainer').appendTo(parentContainer);
// rendering the top level display
}
getTreeData();
//top level rendering! Lower levels are rendered in event handlers.
$(this).each(function () {
renderTopLevel($(this));
});
return this;
};
// Private function for debugging.
function debug(debugText) {
if (window.console && window.console.log) {
window.console.log(debugText);
}
};
}(jQuery));

Just use one more class variable and pass this to it. Usually I call it self. So var self = this; in constructor of your plugin Class and you are good to go.
Object oriented way:
function YourPlugin(){
var self = this;
}
YourPlugin.prototype = {
constructor: YourPlugin,
clickHandler: function(){
// here the self works
}
}
Check this Fiddle
Or simple way of passing data to eventHandler:
$( "#foo" ).bind( "click", {
self: this
}, function( event ) {
alert( event.data.self);
});

You could use the jQuery proxy function:
$(yourElement).bind("click", $.proxy(this.yourFunction, this));
You can then use this in yourFunction as the this in your plugin.

Deleting todos not working correctly

When a todo is created,I push it onto this array:
$scope.$on('todo:created',function(event,todo){
$scope.model.todos.push(todo);
});
I am trying to delete a todo using the $scope.$on functionality like this:
//from a child scope for the item
$scope.actions.remove = function remove()
{
TodoService.delete($scope.model.todo);
$scope.$emit('todo:deleted',$scope.model.todo);
};
//from a parent of the scope which has ng-repeat:
$scope.$on('todo:deleted',function(event,todo){
for(var i =0;i<$scope.model.todos.length;i++)
{
if(todo._id === $scope.model.todos[i]._id)
{
console.log(i);
$scope.model.todos.splice(i,1);
break;
}
}
});
I find that this seemingly normal code causes a lot of issues:
1)last item gets deleted correctly
2)when deleting the penultimate item,the last item gets deleted
3)all other items are unresponsive on delete
I find that the UI renders with the correct items deleted on page reload.
I have tried changing the code to:
$scope.$on('todo:deleted',function(event,todo){
$scope.model.todos = $.grep($scope.model.todos, function (todoItem, i) {
if (todoItem._id === todo._id) {
console.log(i);
return false;
} else {
return true;
}
});
});
The entire code can be found here on github
EDIT:
My code uses ng-repeat like this:
<section class="ui three column doubling page grid">
<div class="column" ng-repeat="todo in model.todos track by $index">
<todo-item value="todo"></todo-item>
</div>
</section>
UPDATE:
I have tried to accomplish the delete using this code:
var onItemDeleted = function onItemDeleted(todo){
var todos = $scope.model.todos;
var checkIndex = function checkIndex(t){
return t._id !== todo._id;
};
todos = todos.filter(checkIndex);
//$scope.model.todos = todos;
};
$scope.$on('todo:deleted',function(event,todo){
$scope.$apply(onItemDeleted(todo));
});
var onTodoAdded = function onTodoAdded(todo){
var todos = $scope.model.todos;
todos.push(todo);
};
$scope.$on('todo:created',function(event,todo){
$scope.$apply(onTodoAdded(todo));
});
In both these cases,I get the error:
Error: [$rootScope:inprog] $digest already in progress
http://errors.angularjs.org/1.3.15/$rootScope/inprog?p0=%24digest
at REGEX_STRING_REGEXP (angular.js:66)
at beginPhase (angular.js:14823)
at Scope.$get.Scope.$apply (angular.js:14567)
at app.js:218
at Scope.$get.Scope.$emit (angular.js:14715)
at app.js:264
at processQueue (angular.js:13251)
at angular.js:13267
at Scope.$get.Scope.$eval (angular.js:14469)
at Scope.$get.Scope.$digest (angular.js:14285)
I have tried replacing the data by replacing the data from the service like this:
$scope.$on('todo:deleted',function(event,todo){
var todosPromise = TodoService.get();
todosPromise.then(function(data){
$scope.model.todos = data;
});
});
And I have changed the event code to fire only after the delete operation is completed:
$scope.actions.remove = function remove(id)
{
TodoService.deleteItem($scope.model.todo)
.then(function(){
$scope.$emit('todo:deleted',$scope.model.todo);
})
.catch(function(err){
console.log(err,err.stack);
});
};
I find that the data from the service or upon splicing is obtained correctly but the wrong element is pulled by ng-repeat,is it because I am using track by $index.

I faced some issues with splice and used $grep to fix those issues.
Can you try the below code:
$scope.$on('todo:deleted',function(event, todo) {
$scope.model.todos = $.grep($scope.model.todos, function (todoItem, i) {
if (todoItem._id === todo._id) {
return false;
console.log(i);
} else {
return true;
}
});
});

Can't bind or render Rich Text from REST with Knockout

I'm getting data back and it does render Title, but can't seem to render rich text.
markup:
<div id="bodyarea">
<div data-bind=foreach:list>
<span data-bind="text:Title" />
<div data-bind="html: RichData"></div>
</div>
</div>
<p id="myarea"></p>
ko:
function LoadLists() {
var listItems = [];
var count = 0;
$.getJSON("https://myserver.com/sites/knockout/_api/lists/getbytitle('List%20One')/items?$filter=Title eq
'zzzz'",
function (data, textstatus, jqXHR) {
$(data.value).each(function (index, item) {
count++;
var koItem = {};
koItem.Title = item.Title;
koItem.RichData = item.Rich;
listItems.push(koItem);
if (data.value.length == count) {
var vm =
{
list: ko.observableArray(listItems)
};
ko.applyBindings(vm, document.getElementById("bodyarea"));
}
})
});
}
$(document).ready(function () { LoadLists(); });

In general, with knockout, you should not:
Call applyBindings more than once
Call applyBindings inside an ajax call
Create a viewModel as a plain object (usually, sometimes it's alright)
Do knockout databinding inside jQuery event handlers.
Code:
// this is a reusable view model for each item. it takes a raw item from the ajax return, and creates observables for each property.
var ListItem = function (item) {
var self = this;
self.Title = ko.observable(item.Title);
self.RichData = ko.observable(item.Rich);
}
// Your viewModel. Constructor-esque syntax is pretty standard.
var ViewModel = function () {
var self = this;
// this is your list array.
self.list = ko.observableArray();
// This is a your reusable function to load lists, when it returns, it maps each item
// in data.value to a ListItem viewModel and puts them all in the lists observableArray
self.loadList = function() {
$.getJSON('yourUrl', function(data) {
var items = data.value.map(function(item) { return new ListItem(item); });
self.list(items);
}
};
};
// When the document is ready, create a view model and apply bindings once. Then call loaLists to initialize
$(document).ready(function () {
var vm = new ViewModel();
ko.applyBindings(vm);
vm.loadList();
});

AngularJS : How to run JavaScript from inside Directive after directive is compiled and linked

I have a responsive template that I am trying to use with my Angularjs app. This is also my first Angular app so I know I have many mistakes and re-factoring in my future.
I have read enough about angular that I know DOM manipulations are suppose to go inside a directive.
I have a javascript object responsible for template re-sizes the side menu and basically the outer shell of the template. I moved all of this code into a directive and named it responsive-theme.
First I added all the methods that are being used and then I defined the App object at the bottom. I removed the function bodies to shorten the code.
Basically the object at the bottom is a helper object to use with all the methods.
var directive = angular.module('bac.directive-manager');
directive.directive('responsiveTheme', function() {
return {
restrict: "A",
link: function($scope, element, attrs) {
// IE mode
var isRTL = false;
var isIE8 = false;
var isIE9 = false;
var isIE10 = false;
var sidebarWidth = 225;
var sidebarCollapsedWidth = 35;
var responsiveHandlers = [];
// theme layout color set
var layoutColorCodes = {
};
// last popep popover
var lastPopedPopover;
var handleInit = function() {
};
var handleDesktopTabletContents = function () {
};
var handleSidebarState = function () {
};
var runResponsiveHandlers = function () {
};
var handleResponsive = function () {
};
var handleResponsiveOnInit = function () {
};
var handleResponsiveOnResize = function () {
};
var handleSidebarAndContentHeight = function () {
};
var handleSidebarMenu = function () {
};
var _calculateFixedSidebarViewportHeight = function () {
};
var handleFixedSidebar = function () {
};
var handleFixedSidebarHoverable = function () {
};
var handleSidebarToggler = function () {
};
var handleHorizontalMenu = function () {
};
var handleGoTop = function () {
};
var handlePortletTools = function () {
};
var handleUniform = function () {
};
var handleAccordions = function () {
};
var handleTabs = function () {
};
var handleScrollers = function () {
};
var handleTooltips = function () {
};
var handleDropdowns = function () {
};
var handleModal = function () {
};
var handlePopovers = function () {
};
var handleChoosenSelect = function () {
};
var handleFancybox = function () {
};
var handleTheme = function () {
};
var handleFixInputPlaceholderForIE = function () {
};
var handleFullScreenMode = function() {
};
$scope.App = {
//main function to initiate template pages
init: function () {
//IMPORTANT!!!: Do not modify the core handlers call order.
//core handlers
handleInit();
handleResponsiveOnResize(); // set and handle responsive
handleUniform();
handleScrollers(); // handles slim scrolling contents
handleResponsiveOnInit(); // handler responsive elements on page load
//layout handlers
handleFixedSidebar(); // handles fixed sidebar menu
handleFixedSidebarHoverable(); // handles fixed sidebar on hover effect
handleSidebarMenu(); // handles main menu
handleHorizontalMenu(); // handles horizontal menu
handleSidebarToggler(); // handles sidebar hide/show
handleFixInputPlaceholderForIE(); // fixes/enables html5 placeholder attribute for IE9, IE8
handleGoTop(); //handles scroll to top functionality in the footer
handleTheme(); // handles style customer tool
//ui component handlers
handlePortletTools(); // handles portlet action bar functionality(refresh, configure, toggle, remove)
handleDropdowns(); // handle dropdowns
handleTabs(); // handle tabs
handleTooltips(); // handle bootstrap tooltips
handlePopovers(); // handles bootstrap popovers
handleAccordions(); //handles accordions
handleChoosenSelect(); // handles bootstrap chosen dropdowns
handleModal();
$scope.App.addResponsiveHandler(handleChoosenSelect); // reinitiate chosen dropdown on main content resize. disable this line if you don't really use chosen dropdowns.
handleFullScreenMode(); // handles full screen
},
fixContentHeight: function () {
handleSidebarAndContentHeight();
},
setLastPopedPopover: function (el) {
lastPopedPopover = el;
},
addResponsiveHandler: function (func) {
responsiveHandlers.push(func);
},
// useful function to make equal height for contacts stand side by side
setEqualHeight: function (els) {
var tallestEl = 0;
els = jQuery(els);
els.each(function () {
var currentHeight = $(this).height();
if (currentHeight > tallestEl) {
tallestColumn = currentHeight;
}
});
els.height(tallestEl);
},
// wrapper function to scroll to an element
scrollTo: function (el, offeset) {
pos = el ? el.offset().top : 0;
jQuery('html,body').animate({
scrollTop: pos + (offeset ? offeset : 0)
}, 'slow');
},
scrollTop: function () {
App.scrollTo();
},
// wrapper function to block element(indicate loading)
blockUI: function (ele, centerY) {
var el = jQuery(ele);
el.block({
message: '<img src="./assets/img/ajax-loading.gif" align="">',
centerY: centerY !== undefined ? centerY : true,
css: {
top: '10%',
border: 'none',
padding: '2px',
backgroundColor: 'none'
},
overlayCSS: {
backgroundColor: '#000',
opacity: 0.05,
cursor: 'wait'
}
});
},
// wrapper function to un-block element(finish loading)
unblockUI: function (el) {
jQuery(el).unblock({
onUnblock: function () {
jQuery(el).removeAttr("style");
}
});
},
// initializes uniform elements
initUniform: function (els) {
if (els) {
jQuery(els).each(function () {
if ($(this).parents(".checker").size() === 0) {
$(this).show();
$(this).uniform();
}
});
} else {
handleUniform();
}
},
updateUniform : function(els) {
$.uniform.update(els);
},
// initializes choosen dropdowns
initChosenSelect: function (els) {
$(els).chosen({
allow_single_deselect: true
});
},
initFancybox: function () {
handleFancybox();
},
getActualVal: function (ele) {
var el = jQuery(ele);
if (el.val() === el.attr("placeholder")) {
return "";
}
return el.val();
},
getURLParameter: function (paramName) {
var searchString = window.location.search.substring(1),
i, val, params = searchString.split("&");
for (i = 0; i < params.length; i++) {
val = params[i].split("=");
if (val[0] == paramName) {
return unescape(val[1]);
}
}
return null;
},
// check for device touch support
isTouchDevice: function () {
try {
document.createEvent("TouchEvent");
return true;
} catch (e) {
return false;
}
},
isIE8: function () {
return isIE8;
},
isRTL: function () {
return isRTL;
},
getLayoutColorCode: function (name) {
if (layoutColorCodes[name]) {
return layoutColorCodes[name];
} else {
return '';
}
}
};
}
};
});
Originally the App.init() object method would be called at the bottom of any regular html page, and I have others that do certain things also that would be used on specific pages like Login.init() for the login page and so forth.
I did read that stackoverflow post
"Thinking in AngularJS" if I have a jQuery background? and realize that I am trying to go backwards in a sense, but I want to use this template that I have so I need to retro fit this solution.
I am trying to use this directive on my body tag.
<body ui-view="dashboard-shell" responsive-theme>
<div class="page-container">
<div class="page-sidebar nav-collapse collapse" ng-controller="SidemenuController">
<sidemenu></sidemenu>
</div>
<div class="page-content" ui-view="dashboard">
</div>
</div>
</body>
So here is my problem. This kinda sorta works. I don't get any console errors but when I try to use my side menu which the javascript for it is in the directive it doesn't work until I go inside the console and type App.init(). After that all of the template javascript works. I want to know how to do responsive theme stuff in these directives. I have tried using it both in the compile and link sections. I have tried putting the code in compile and link and calling the $scope.App.init() from a controller and also at the bottom after defining everything. I also tried putting this in jsfiddle but can't show a true example without having the console to call App.init().
My end design would be having some way to switch the pages through ui-router and when a route gets switched it calls the appropriate methods or re-runs the directive or something. The only method that will run on every page is the App.init() method and everything else is really page specific. And technically since this is a single page app the App.init() only needs to run once for the application. I have it tied to a parent template inside ui-router and the pages that will switch all use this shell template. There are some objects that need to access other to call their methods.
Im sorry in advance for maybe a confusing post. I am struggling right now trying to put together some of the ways that you do things from an angular perspective. I will continue to edit the post as I get responses to give further examples.

You said I have read enough about angular that I know DOM manipulations are suppose to go inside a directive but it sounds like you missed the point of a directive. A directive should handle DOM manipulation, yes, but not one directive for the entire page. Each element (or segment) of the page should have its own directive (assuming DOM manip needs to be done on that element) and then the $controller should handle the interactions between those elements and your data (or model).
You've created one gigantic directive and are trying to have it do way too much. Thankfully, you've kinda sorta designed your code in such a way that it shouldn't be too hard to break it up into several directives. Basically, each of your handle functions should be its own directive.
So you'd have something like:
.directive('sidebarMenu', function(){
return {
template: 'path/to/sidebar/partial.html',
link: function(scope, elem, attrs){
// insert the code for your 'handleSidebarMenu()' function here
}
};
})
.directive('horizontalMenu', function(){
return {
template: 'path/to/horizontal/partial.html',
link: function(scope, elem, attrs){
// insert the code for your 'handleHorizontalMenu()' function here
}
};
})
and then your view would look something like:
<body ui-view="dashboard-shell" responsive-theme>
<div class="page-container">
<div class="page-sidebar nav-collapse collapse">
<horizontal-menu></horizontal-menu>
<sidebar-menu></sidebar-menu>
</div>
<div class="page-content" ui-view="dashboard">
</div>
</div>
</body>
And then you don't need a SidebarmenuController because your controller functions shouldn't be handling DOM elements like the sidebar. The controller should just handling the data that you're going to display in your view, and then the view (or .html file) will handle the displaying and manipulation of that data by its use of the directives you've written.
Does that make sense? Just try breaking that huge directive up into many smaller directives that handle specific elements or specific tasks in the DOM.