The client-side controller calls $A.createComponent () to create a lightning:button with a local ID (aura:id) and a handler for the onclick attribute. The function (newButton,...) callback appends the button to the body of c:createComponent.
Full Answer
How to create a lightning web component using Salesforce CLI?
The target directory must be named lwc --type — This specifies that you want to create a Lightning Web Component. As you experienced, it’s easy to use Salesforce CLI in your development process. If you want to use Visual Studio Code for this instead, right-click the lwc folder or open the Command Palette in Visual Studio Code.
How to create a lightning web component in Visual Studio Code?
We can use Visual Studio Code for creating a Lightning web component, just as we did to create the Salesforce DX project. Or we can use Salesforce CLI directly. Open Visual Studio Code. Press Command + Shift + P on macOS or Ctrl + Shift + P on Windows or Linux, then type focus terminal.
How to create a scratch Org in Salesforce?
To authenticate Dev Hub is a precondition for creating a scratch org, which is an ephemeral environment for developing on the Salesforce Platform. We create one in the next step. In Visual Studio Code, press Command + Shift + P on macOS or Ctrl + Shift + P on Windows or Linux.
How do I use Salesforce CLI with Visual Studio Code?
As you experienced, it’s easy to use Salesforce CLI in your development process. If you want to use Visual Studio Code for this instead, right-click the lwc folder or open the Command Palette in Visual Studio Code. Both provide the option SFDX: Create Lightning Web Component, which then invokes Salesforce CLI.
What is a createComponent?
createComponent() Create a component from a type and a set of attributes. This method accepts the name of a type of component, a map of attributes, and a callback to notify the caller.
How do you make a dynamic component of lightning?
To dynamically create a component in the body of another component, use $A. createComponents() to create the components. In the function callback, nest the components by setting the inner component in the body of the outer component.
What is a getCallback?
getCallback() to wrap any code that modifies a component outside the normal rerendering lifecycle, such as in a setTimeout() call. The $A. getCallback() call ensures that the framework rerenders the modified component and processes any enqueued actions.
What is the use of a enqueueAction action in lightning?
enqueueAction(action) sends the request the server. More precisely, it adds the call to the queue of asynchronous server calls. That queue is an optimization feature of Lightning.
What is renderedCallback in LWC?
From the documentation, we know that renderedCallback method is called when component is completely rendered and it can be called multiple times. So if we want to perform any operation after rendering, we would put that code inside renderedCallback.
What is Aura dependency?
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What is $a and a Util in lightning?
$A is how you gain access to the underlying Aura framework, such as enqueuing actions, getting application events, managing the Aura rendering life cycle, and various utility methods.
What is callback in Salesforce?
Remote Objects sends all requests to the Salesforce service asynchronously. Your code handles responses to Remote Objects operations in a callback function that you provide. Callback functions handle updating the page with the results of the operation and errors that are returned.
What is promise in lightning?
Promises execute their resolve and reject functions asynchronously so the code is outside the Lightning event loop and normal rendering lifecycle. If the resolve or reject code makes any calls to the Lightning Component framework, such as setting a component attribute, use $A. getCallback() to wrap the code.
What is the purpose of enqueueAction?
enqueueAction() The framework queues up actions before sending them to the server. This mechanism is largely transparent to you when you're writing code but it enables the framework to minimize network traffic by batching multiple actions into one request (XHR).
What is a enqueueAction?
enqueueAction(action) adds the server-side controller action to the queue of actions to be executed. All actions that are enqueued will run at the end of the event loop.
What is $a in lightning component?
The $A namespace is the entry point for using the framework in JavaScript code. It allows you to interact with the framework.
Client-Side Versus Server-Side Component Creation
The $A.createComponent () and $A.createComponents () methods support both client-side (synchronous) and server-side (asynchronous) component creation. For performance and other reasons, client-side creation is preferred.
Syntax
type —The type of component to create; for example, "lightning:button".
Creating Nested Components
To dynamically create a component in the body of another component, use $A.createComponents () to create the components. In the function callback, nest the components by setting the inner component in the body of the outer component. This example creates a lightning:icon component in the body of a lightning:card component.
Destroying Dynamically Created Components
After a component that is declared in markup is no longer in use, the framework automatically destroys it and frees up its memory.
Create a Salesforce DX Project
The basic foundation for interacting with an org using Salesforce CLI is a Salesforce DX project. A project consists of several local configuration files, as well as the code you want to deploy. In Salesforce terms we call this code metadata, which is the foundation of the Salesforce Platform.
Authorize Your Dev Hub
The next step is to authenticate Dev Hub. If you're using a Trailhead Playground you can learn in Get Your Trailhead Playground Username and Password how to get the credentials for the next step.
Create a Scratch Org
In Visual Studio Code, press Command + Shift + P on macOS or Ctrl + Shift + P on Windows or Linux.
Create a Lightning Web Component
Creating a Lightning web component is a straightforward process. And Salesforce CLI already created a project structure that helps make getting started even easier.
Adding Code and Metadata to Your First Lightning Web Component
Let’s take a look now at the files that make up a Lightning web component. For that we’re going to copy and paste some HTML, JavaScript, and XML that we’ve already prepared for you. We start with the myFirstWebComponent.js-meta.xml file.
Verify Step
You’ll be completing this project in your own hands-on org. Click Launch to get started, or click the name of your org to choose a different one.
