Lightning Components Developer's Guide

Introducing the Lightning Component Framework
Quick Start
Creating Components
Working with UI Components
Using Expressions
Supporting Accessibility
Communicating with Events
Creating Apps
Debugging
Reference
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aura:if

aura:if renders the content within the tag if the isTrue attribute evaluates to true.

The framework evaluates the isTrue expression and instantiates components either in its body or else attribute.

aura:if instantiates the components in either its body or the else attribute, but not both. aura:renderIf instantiates both the components in its body and the else attribute, but only renders one. If the state of isTrue changes, aura:if has to first instantiate the components for the other state and then render them. We recommend using aura:if instead of aura:renderIf to improve performance.

Note

Attribute Name Type Description
else ComponentDefRef[] The markup to render when isTrue evaluates to false. Set this attribute using the aura:set tag.
isTrue string Required. An expression that determines whether the content is displayed. If it evaluates to true, the content is displayed.

Example

This snippet of markup uses the <aura:if> tag to conditionally display an edit button.

1<aura:attribute name="edit" type="Boolean" default="true"/>
2<aura:if isTrue="{!v.edit}">
3    <ui:button label="Edit"/>
4    <aura:set attribute="else">
5        You can’t edit this.
6    </aura:set>
7</aura:if>

If the edit attribute is set to true, a ui:button displays. Otherwise, the text in the else attribute displays.