Category Archives: Salesforce

Salesforce Test Class Data For ContentDocumentLink

Sample Code:

//Create Document Parent Record
Account acc = new Account(Name='Test Account');
Insert acc;

//Create Document
ContentVersion cv = new ContentVersion();
cv.Title = 'Test Document';
cv.PathOnClient = 'TestDocument.pdf';
cv.VersionData = Blob.valueOf('Test Content');
cv.IsMajorVersion = true;
Insert cv;

//Get Content Documents
Id conDocId = [SELECT ContentDocumentId FROM ContentVersion WHERE Id =:cv.Id].ContentDocumentId;

//Create ContentDocumentLink 
ContentDocumentLink cdl = New ContentDocumentLink();
cdl.LinkedEntityId = acc.Id;
cdl.ContentDocumentId = conDocId;
cdl.shareType = 'V';
Insert cdl;

Component Events vs Application Events

Component Events:

  • Component Events can be handled by same component or a component that instantiates or contains the component.
  • The component events can only be registered in child component and handled by parent component.
  • We use attribute type="COMPONENT" in the aura:event tag for an component event.
  • While handling component events, we need to specify name attribute in aura:handler. The name attribute in aura:handler must match the name attribute in the aura:registerEvent tag in the Child Component that fires the event.
  • We use cmp.getEvent("evtName") in JavaScript to get an instance of the Component type event.

Application Events:

  • Application Events are handled by any component have handler defined for event.These events are essentially a traditional publish-subscribe model.
  • Application event can be used through out the application.
  • We use attribute type="APPLICATION" in the aura:event tag for an application event.
  • While handling application events, no need to specify name attribute in aura:handler.
  • We use $A.get("e.myNamespace:myAppEvent") in JavaScript to get an instance of the Application type event.

Application Events in Salesforce Lightning Framework

Lightning framework is based on event-driven architecture which allows to communicate between different events. Lightning events are fired from JavaScript controller actions that are triggered by a user interacting with the user interface.

The communication between components are handled by events. There are two types of custom events in the Lightning Framework:

  • Component Events
  • Application Events

Application Events are handled by any component have handler defined for event.These events are essentially a traditional publish-subscribe model.

Application Event Example:
In below example by using Application event, I’m passing the values from Component1 to a Component2 via event.

Sample Application Event:
Create a sample application type event. Use type=”APPLICATION” in the aura:event tag for an application event. The attribute type is the one that will differentiate Application event from Component event.

<!--SampleApplicationEvent.evt-->
<aura:event type="Application" description="Sample Application Event">
    <aura:attribute name="message" type="String" />
</aura:event>

Component1:

<!--Component1.cmp-->
<aura:component>
    <aura:registerEvent name="SampleApplicationEvent" type="c:SampleApplicationEvent"/>
    <lightning:button label="Click to fire the event" variant="brand" onclick="{!c.component1Event}"/>
</aura:component>

Component1 JS Controller:
Use $A.get(“e.myNamespace:myAppEvent”) in JavaScript to get an instance of the myAppEvent event in the myNamespace namespace.
To set the attribute values of event, call event.setParam() or event.setParams().

({
    component1Event : function(cmp, event,helper) { 
        //Get the event using event name. 
        var appEvent = $A.get("e.c:SampleApplicationEvent"); 
        //Set event attribute value
        appEvent.setParams({"message" : "Welcome "}); 
        appEvent.fire(); 
    }
})

Component2:
The application event handled by the Component2 that fired using aura:handler in the markup.
The action attribute of aura:handler sets the client-side controller action to handle the event.

<!--Component2.cmp-->
<aura:component>
    <aura:attribute name="eventMessage" type="String"/> 
    <aura:handler event="c:SampleApplicationEvent" action="{!c.component2Event}"/>
    <div class="slds-m-around_xx-large">
        <p>{!v.eventMessage}</p> 
    </div>
</aura:component>

Component2 JS Controller:

({
    component2Event : function(cmp, event) { 
        //Get the event message attribute
        var message = event.getParam("message"); 
        //Set the handler attributes based on event data 
        cmp.set("v.eventMessage", message + 'Biswajeet');         
    }
})

Lightning Application:

<aura:application extends="force:slds">
    <c:Component1/>
    <c:Component2/>
</aura:application>

Output:

Component Events in Salesforce Lightning Framework

Lightning framework is based on event-driven architecture which allows to communicate between different events. Lightning events are fired from JavaScript controller actions that are triggered by a user interacting with the user interface.

The communication between components are handled by events. There are two types of custom events in the Lightning Framework:

  • Component Events
  • Application Events

Component Events can be handled by same component or a component that instantiates or contains the component. The component events can only be registered in child component and handled by parent component.

Component Event Example:
In below example by using component event, I’m passing the values from a child component to a parent component via event.

Sample Component Event:
Create a sample component type event. Use type=”COMPONENT” in the aura:event tag for an component event. The attribute type is the one that will differentiate Component event from Application event.

<!--SampleComponentEvent.evt-->
<aura:event type="COMPONENT" description="Sample Component Event">
    <aura:attribute name="message" type="String" default="Hello World!!" />
</aura:event>

Child Component:
The event is registered in this component by using aura:registerEvent in its markup.

<!--Child.cmp-->
<aura:component >
    <aura:registerEvent name="sampleCmpEvent" type="c:SampleComponentEvent" />
    <lightning:button label="Click to fire the event" variant="brand" onclick="{!c.childComponentEvent}"/>
</aura:component>

Child Component JS Controller:
To set the attribute values of event, call event.setParam() or event.setParams().

({
    childComponentEvent : function(cmp, event,helper) { 
        //Get the event using registerEvent name. 
        var cmpEvent = cmp.getEvent("sampleCmpEvent"); 
        //Set event attribute value
        cmpEvent.setParams({"message" : "Welcome "}); 
        cmpEvent.fire(); 
    }
})

Parent Component:
The component event handled by the Parent Component that fired using aura:handler in the markup.
The name attribute in aura:handler must match the name attribute in the aura:registerEvent tag in the Child Component that fires the event.
The action attribute of aura:handler sets the client-side controller action to handle the event.

<!--Parent.cmp-->
<aura:component >
    <aura:attribute name="eventMessage" type="String"/> 
    <aura:handler name="sampleCmpEvent" event="c:SampleComponentEvent" action="{!c.parentComponentEvent}"/>
    <div class="slds-m-around_xx-large">
        <c:Child /> 
        <p>{!v.eventMessage}</p> 
    </div>
</aura:component>

Parent Component JS Controller:

({
    parentComponentEvent : function(cmp, event) { 
        //Get the event message attribute
        var message = event.getParam("message"); 
        //Set the handler attributes based on event data 
        cmp.set("v.eventMessage", message + 'Biswajeet');         
    } 
})

Output:

System Events in Lightning Framework

System events are fired automatically by the Lightning framework such as during component initialization, attribute value change, rendering etc. All Components can register for system events in their HTML markup.

We can handle these events in the Lightning apps or components, and within the Salesforce mobile app. Here are few examples of system events.

Event Name Description
aura:doneRendering Indicates that the initial rendering of the root application has completed.
aura:doneWaiting Indicates that the app is done waiting for a response to a server request.
aura:locationChange Indicates that the hash part of the URL has
changed.
aura:noAccess Indicates that a requested resource is not accessible due to
security constraints on that resource.
aura:systemError Indicates that an error has occurred.
aura:valueChange Indicates that an attribute value has
changed.
aura:valueDestroy Indicates that a component has been
destroyed.
aura:valueInit Indicates that an app or component has been
initialized.
aura:valueRender Indicates that an app or component has been rendered or
rerendered.
aura:waiting Indicates that the app is waiting for a response to a server request.