The Salesforce mobile app and Lightning Experience handle some events, which you can fire in your Aura component. System Events The framework fires several system events during its lifecycle.
Table of Contents
What are application events and component events in Salesforce Lightning?
Application events and component events are the two types of Salesforce Lightning events that are used to communicate and transfer data between two components. What Is Component Event Propagation? Event propagation determines how you communicate in your application.
What is the event attribute in Salesforce?
The event attribute specifies the event being handled. The format is namespace: eventName. In this example, when the event is fired, the handleComponentEvent client-side controller action is called. Component event handlers are associated with the bubble phase by default.
What is the Lightning component framework in Salesforce?
It consists of the Lightning Component Framework, which can be used to create reusable components, customize Salesforce1 applications, and build standalone applications. Using an event-based approach, the framework facilitates communication with the various components.
What is the future of Salesforce Lightning?
Salesforce Lightning, known as the future of Salesforce, comprises the no. innovative tools and technologies that bring several upgrades for enhancing the Salesforce1 Platform. It consists of the Lightning Component Framework, which can be used to create reusable components, customize Salesforce1 applications, and build standalone applications.
How do I use events in Salesforce lightning?
To create a component event in salesforce, navigate File -> New -> Lightning Event in developerconsole. Name the event, enter the description and click submit to create lightning event. The attribute type is the one that will differentiate Component event from Application event. The events can be fired from controller.
How many events are in lightning component?
There are two types of events in the framework: Component events are handled by the component itself or a component that instantiates or contains the component. Application events are handled by all components that are listening to the event.
How do you handle events in Lightning Web components?
You can handle events in HTML (add an event listener in the template) or JavaScript (write an event listener function). We recommend using the HTML approach, as follows. Each tile component listens for the user click because the tile component’s HTML (tile. html) contains an onclick event listener.
How do you communicate between two lightning components using events?
Steps to communicate between two Lightning Components using events:Create an event.Create two lightning components: Child component and parent component.Register the event in the child component and fired the event in the child component JavaScript controller action.Handle the event in the parent component.
What are different types of events in Salesforce lightning?
Salesforce Lightning Events are broadly classified into four:System Events.Lightning Application Events from library.Application Events.Component Events.
Why do we use events in lightning?
In simple terms, Events are used to establish communication between components. If you want to send the data from one component to another component, we use events. You fire an event in the source component and this event will be handled by any other component depends on the type.
What is the difference between aura and LWC?
Aura and LWC can be able to communicate using Public API’s and Events. LWC can be embedded inside Aura Components, but Aura Components cannot be embedded inside LWC.
What are events in Lightning component?
A component event in the lightning component is an event that is fired by another lightning component. A component event can either be managed by the component itself or it can be managed by any of another component that is already present in the hierarchy that gets that particular event.
What is event bubbling in LWC?
In this behavior, the event bubbles up the DOM, but don’t cross the shadow boundary. In simple terms, It bubbles up inside the current template, in which event is fired, but it would not cross it’s boundary. For example :- There are two component, where parent component contain child component.
What is the difference between component event and application event?
Component events can only be handled by components above them in the containment hierarchy so their usage is more localized to the components that need to know about them. Application events are best used for something that should be handled at the application level, such as navigating to a specific record.
What is bubble and capture phase in lightning?
The framework supports capture and bubble phases for the propagation of component events. These phases are similar to DOM handling patterns and provide an opportunity for interested components to interact with an event and potentially control the behavior for subsequent handlers.
How do you communicate between parent and child in lightning component?
Create and code a new parent component named augmentor :Create a Lightning web component named augmentor .In augmentor.js, paste this code inside the Augmentor class: … Save the file.Open augmentor.html and add this code between the template tags: … Save the file.More items…
What is application event?
Application events allow communication between components that are in separate parts of the application and have no direct containment relationship. Actions and Events. The framework uses events to communicate data between components. Events are usually triggered by a user action.
When does a component rerender?
A component is instantiated, rendered, and rerendered during its lifecycle. A component rerenders only when there’s a programmatic or value change that requires a rerender. For example, if a browser event triggers an action that updates the component’s data, the component rerenders.
Can component events be handled by component events?
Always try to use a component event instead of an application event, if possible. Component events can only be handled by components above them in the containment hierarchy so their usage is more localized to the components that need to know about them. Application events are best used for something that should be handled at …
Can you fire an event in Aura?
You can fire Aura events from JavaScript code outside an Aura app. For example, your Aura app might need to call out to some non-Aura code, and then have that code communicate back to your Aura app once it’s done. Events Best Practices. Here are some best practices for working with events.
Event Handling Phases
Component event handlers are associated with the bubble phase by default. To add a handler for the capture phase instead, use the phase attribute.
Get the Source of an Event
In the client-side controller action for an <aura:handler> tag, use evt.getSource () to find out which component fired the event, where evt is a reference to the event. To retrieve the source element, use evt.getSource ().getElement ().
Component Relationships
In this app, multiple components work together; some components are nested inside other components. Just as you nest HTML elements inside each other, Lightning web components—which are custom HTML elements—can be nested inside other Lightning web components.
Events Up, Properties Down
In a complex component (one that contains several parent and child components), the components can communicate up and down.
Passing Information Down
Information can be passed down using public properties and public methods.
Handling Events in HTML
So our selector app needs to handle one type of event—the user clicking a tile. When this happens, the detail component should re-render with the information from the related tile. You can handle events in HTML (add an event listener in the template) or JavaScript (write an event listener function). We recommend using the HTML approach, as follows.
Selector App Event Pattern
In our product selector app, we use a complex component (one that contains several parent and child components), We recommend that you propagate the event up through the component hierarchy, so parent components can respond to child events.
Deploy Your Files to Your Org
Let’s deploy these files to your Dev Hub enabled org to see how it works. Using the same steps you performed in the last unit, deploy your new files, open the org, and create a page in Lightning App Builder with this app.
What is an event in Salesforce?
An event is a notification that makes an interested entity discover that something has happened and can now take the appropriate action. The interested entity is defined as the components that you create in Salesforce Lightning. The components will register for the events they are interested in and trigger it if necessary.
What is Salesforce Lightning?
Salesforce Lightning, known as the future of Salesforce, comprises the no. innovative tools and technologies that bring several upgrades for enhancing the Salesforce1 Platform. It consists of the Lightning Component Framework, which can be used to create reusable components, customize Salesforce1 applications, and build standalone applications.
What are the propagation rules for component events?
1.Event Propagation rules for the component events: Component events are fired by the child components and processed by the parent component. MiddleComp is the immediate parent of BottomComp, and TopComp is the immediate parent of MiddleComp and MiddleComp2. 2) Bubble phase: If we do not specify any phase, it is considered a bubble phase.
How to stop an event from propagating?
1. In this event object, you can use the stopPropagation () method to stop the event from propagating to other components.#N#2. You can use the event.pause () to pause the event.#N#3. You can call pause () or resume () in the capture or bubble phases.
What is system event?
System events are also part of the containment hierarchy fired automatically by the framework during its life cycles, such as during component initialization, changing of an attribute value, and rendering. This movement of events is also known as propagation that determines the sequence in which the event can be processed.
What is event propagation phase?
Depending on the type of phase, events can be handled starting from the innermost or outermost container. Frames allow you to process events in different phases. In these phases, you have the flexibility to decide how effectively you can handle the event for your application.
Which container is the first to handle events?
The innermost container is the first to handle events, while the top container is the last to handle events.It is a tree of components with a top-level container as its root. The user actions and events trigger the events resulting from actions and are different from application and component events.
