Is there any way to make an expression for something like ng-class to be a conditional?
For example, I have tried the following:
<span ng-class="{test: 'obj.value1 == \'someothervalue\''}">test</span>
The issue with this code is that no matter what obj.value1 is, the class test is always applied to the element. Doing this:
<span ng-class="{test: obj.value2}">test</span>
As long as obj.value2 does not equal a truthy value, the class in not applied. Now I can work around the issue in the first example by doing this:
<span ng-class="{test: checkValue1()}">test</span>
Where the checkValue1 function looks like this:
$scope.checkValue1 = function() {
return $scope.obj.value === 'somevalue';
}
I am just wondering if this is how ng-class is supposed to work. I am also building a custom directive where I would like to do something similar to this. However, I can't find a way to watch an expression (and maybe that is impossible and the reason why it works like this).
Here is a plnkr to show what I mean.
Your first attempt was almost right, It should work without the quotes.
{test: obj.value1 == 'someothervalue'}
Here is a plnkr.
The ngClass directive will work with any expression that evaluates truthy or falsey, a bit similar to Javascript expressions but with some differences, you can read about here.
If your conditional is too complex, then you can use a function that returns truthy or falsey, as you did in your third attempt.
Just to complement: You can also use logical operators to form logical expressions like
ng-class="{'test': obj.value1 == 'someothervalue' || obj.value2 == 'somethingelse'}"
Using ng-class inside ng-repeat
<table>
<tbody>
<tr ng-repeat="task in todos"
ng-class="{'warning': task.status == 'Hold' , 'success': task.status == 'Completed',
'active': task.status == 'Started', 'danger': task.status == 'Pending' } ">
<td>{{$index + 1}}</td>
<td>{{task.name}}</td>
<td>{{task.date|date:'yyyy-MM-dd'}}</td>
<td>{{task.status}}</td>
</tr>
</tbody>
</table>
For each status in task.status a different class is used for the row.
Angular JS provide this functionality in ng-class Directive. In which you can put condition and also assign conditional class. You can achieve this in two different ways.
Type 1
<div ng-class="{0:'one', 1:'two',2:'three'}[status]"></div>
In this code class will be apply according to value of status value
if status value is 0 then apply class one
if status value is 1 then apply class two
if status value is 2 then apply class three
Type 2
<div ng-class="{1:'test_yes', 0:'test_no'}[status]"></div>
In which class will be apply by value of status
if status value is 1 or true then it will add class test_yes
if status value is 0 or false then it will add class test_no
I see great examples above but they all start with curly brackets (json map). Another option is to return a result based on computation. The result can also be a list of css class names (not just map). Example:
ng-class="(status=='active') ? 'enabled' : 'disabled'"
or
ng-class="(status=='active') ? ['enabled'] : ['disabled', 'alik']"
Explanation: If the status is active, the class enabled will be used. Otherwise, the class disabled will be used.
The list [] is used for using multiple classes (not just one).
There is a simple method which you could use with html class attribute and shorthand if/else. No need to make it so complex. Just use following method.
<div class="{{expression == true ? 'class_if_expression_true' : 'class_if_expression_false' }}">Your Content</div>
I am going to show you two methods by which you can dynamically apply ng-class
Step-1
By using ternary operator
<div ng-class="condition?'class1':'class2'"></div>
Output
If your condition is true then class1 will be applied to your element else class2 will be applied.
Disadvantage
When you will try to change the conditional value at run time the class somehow will not changed. So I will suggest you to go for step2 if you have requirement like dynamic class change.
Step-2
<div ng-class="{value1:'class1', value2:'class2'}[condition]"></div>
Output
if your condition matches with value1 then class1 will be applied to your element, if matches with value2 then class2 will be applied and so on. And dynamic class change will work fine with it.
Hope this will help you.
Angular syntax is to use the : operator to perform the equivalent of an if modifier
<div ng-class="{ 'clearfix' : (row % 2) == 0 }">
Add clearfix class to even rows. Nonetheless, expression could be anything we can have in normal if condition and it should evaluate to either true or false.
Using function with ng-class is a good option when someone has to run complex logic to decide the appropriate CSS class.
http://jsfiddle.net/ms403Ly8/2/
HTML:
<div ng-app>
<div ng-controller="testCtrl">
<div ng-class="getCSSClass()">Testing ng-class using function</div>
</div>
</div>
CSS:
.testclass { Background: lightBlue}
JavaScript:
function testCtrl($scope) {
$scope.getCSSClass = function() {
return "testclass ";
}
}
For Angular 2, use this
<div [ngClass]="{'active': dashboardComponent.selected_menu == 'mapview'}">Content</div>
use this
<div ng-class="{states}[condition]"></div>
for example if the condition is [2 == 2], states are {true: '...', false: '...'}
<div ng-class="{true: 'ClassA', false: 'ClassB'}[condition]"></div>
ng-class is a Directive of core AngularJs. In which you can use "String Syntax", "Array Syntax", "Evaluated Expression", " Ternary Operator" and many more options described below:
ngClass Using String Syntax
This is the simplest way to use ngClass. You can just add an Angular variable to
ng-class and that is the class that will be used for that element.
<!-- whatever is typed into this input will be used as the class for the div below -->
<input type="text" ng-model="textType">
<!-- the class will be whatever is typed into the input box above -->
<div ng-class="textType">Look! I'm Words!
Demo Example of ngClass Using String Syntax
ngClass Using Array Syntax
This is similar to the string syntax method except you are able to apply multiple classes.
<!-- both input boxes below will be classes for the div -->
<input type="text" ng-model="styleOne">
<input type="text" ng-model="styleTwo">
<!-- this div will take on both classes from above -->
<div ng-class="[styleOne, styleTwo]">Look! I'm Words!
ngClass Using Evaluated Expression
A more advanced method of using ngClass (and one that you will probably use the most) is to evaluate an expression. The way this works is that if a variable or expression evaluates to true, you can apply a certain class. If not, then the class won't be applied.
<!-- input box to toggle a variable to true or false -->
<input type="checkbox" ng-model="awesome"> Are You Awesome?
<input type="checkbox" ng-model="giant"> Are You a Giant?
<!-- add the class 'text-success' if the variable 'awesome' is true -->
<div ng-class="{ 'text-success': awesome, 'text-large': giant }">
Example of ngClass Using Evaluated Expression
ngClass Using Value
This is similar to the evaluated expression method except you just able to compares multiple values with the only variable.
<div ng-class="{value1:'class1', value2:'class2'}[condition]"></div>
ngClass Using the Ternary Operator
The ternary operator allows us to use shorthand to specify two different classes, one if an expression is true and one for false. Here is the basic syntax for the ternary operator:
ng-class="$variableToEvaluate ? 'class-if-true' : 'class-if-false'">
Evaluating First, Last or Specific Number
If you are using the ngRepeat directive and you want to apply classes to the first, last, or a specific number in the list, you can use special properties of ngRepeat. These include $first, $last, $even, $odd, and a few others. Here's an example of how to use these.
<!-- add a class to the first item -->
<ul>
<li ng-class="{ 'text-success': $first }" ng-repeat="item in items">{{ item.name }}</li>
</ul>
<!-- add a class to the last item -->
<ul>
<li ng-class="{ 'text-danger': $last }" ng-repeat="item in items">{{ item.name }}</li>
</ul>
<!-- add a class to the even items and a different class to the odd items -->
<ul>
<li ng-class="{ 'text-info': $even, 'text-danger': $odd }" ng-repeat="item in items">{{ item.name }}</li>
</ul>
I have the following table markup:
<tr ng-repeat="client in clientsIndex">
<td>{{client.fullName}}</td>
<td>{{item.contactPhone}}</td>
</tr>
When the view for this renders, I see only one column is populated, but nothing logged in the console. Is there a way I can tell angular this is a debugging session, and I'd like to see big screaming error messages if I make a copy and paste mistake?
Surely at the time the {{}} expression is evaluated whatever does that can output a non-blank value at least?
As of Angular 1.1.5 there is support for ternary operators in templates. So you can define something like this to get a default value if undefined:
<tr ng-repeat="client in clientsIndex">
<td>{{client.fullName}}</td>
<td>{{item.contactPhone ? item.contactPhone : 'Error: not defined'}}</td>
</tr>
The general structure is: {{(condition) ? (expression if true) : (expression if false)}}.
For debugging purpose you can select the element using any angular.element("") selectors and see the scope of that element to check the variable you are trying to access inside the element is inside the scope available to that element.Find the example below.i have used an id selector you can use a child selector.
<tr id="canbeReplacedWithChildSelectors" ng-repeat="client in clientsIndex">
<td>{{client.fullName}}</td>
<td>{{item.contactPhone}}</td>
</tr>
angular.element("#canbeReplacedWithChildSelectors").scope() execute this and check client.fullName is available in the scope.in your case angular.element("#canbeReplacedWithChildSelectors").scope().client would give you undefined.
This should be simple. For some reason, when using ng-model inside of ng-repeat it updates all ng-models inside that repeat loop.
Here's the code. Any ideas?
http://plnkr.co/edit/iAgrPwwBMilCyeReeLt9?p=info
Thanks.
Interesting!!!
Problem is that you are resetting row.field with an object from "$scope.columns"
in
<td>
<select ng-model="row.field" ng-options="column.title for column in columns"></select>
</td>
Here, row.field is reset with an object from $scope.columns and if you change this object in one row, as the other rows also use the same object, they repeat the same value.
You can change this model to row.field.type as
<td>
<select ng-model="row.field.type" ng-options="column.type as column.title for column in columns" ng-change="resetRow(row.field)"></select>
</td>
and define $scope.resetRow in your controller to reset other properties based on the field type.
Here is the updated plunker.
I would love to have a feature in ng-options to return a copy of
the object selected instead of the object reference to solve your problem though.
I have an array with classes set in the controller (has to be this way, it's read from page's meta-template). I'd also like to have a conditional classes applied to the same element. Is it possible?
Edit, more info: my html element has classes that originate from two sources - one is a set of classes created by the controller (they are provided by a service outside of my code, I can't have them hardcoded in the view). The other source is an output of a condition (for example: if "$scope.activeElement === name_of_this_element, add 'active' class).
In ng-class directive, I can't use an object notation for unspecified list of classes (the first source) and I have to use an object notation for conditional classes.
Edit: found a solution (see below).
Another option is to write an ng-class in this way
<div ng-class="[item.class, item.errorClass, item.locked ? 'locked-item' : '']"></div>
I found a solution - I placed the "fixed" classes in a regular class attribute (converted that string to an array first) and conditional ones in ng-class object, like this:
<td ng-repeat="cell in row.cells" class="{{cell.cssClass}}" ng-class="{active: condition}">
The fact that you stored a array of classes' name is not relevant here.
HTML
<div ng-class="arrOfClasses[condition]"></div>
Angular
app.controller('myCtrl', function($scope) {
$scope.arrOfClasses = ['class1', 'class2', 'class3'];
$scope.condition = 1; // what ever number here
});
A good way, and also to avoid using {{}} inside class would be with just an expression:
<td ng-repeat="cell in row.cells" ng-class="(condition ? 'active ' : '') + cell.cssClass">
I have an array of 3 items and want them to be "ng-repeated"
<li ng-repeat="item in obj.items id="testobj{{testobj.number}}">
</li>
When I look at the page, it appears that the id of the "li" is just "testobj" for all 3 items and not testobj1 testobj2 testobj3 like I was expecting. What is the issue?
Your ng-repeat attribute is missing a final ".
The {{ }} binding is probably coming back with no data and so being treated as if it was an empty string. I see no reference to testobj (the scope variable) anywhere outside of your binding. Is this defined, or should your id read id="testobj{{item.number}}" or something similar?