Lightning Aura Components Developer Guide
jComponent Body
The <aura:component> tag can contain tags, such as <aura:attribute>, <aura:registerEvent>, <aura:handler>, <aura:set>, and so on. Any free markup that is not enclosed in one of the tags allowed in a component is assumed to be part of the body and is set in the body attribute.
The body attribute has type Aura.Component[]. It can be an array of one component, or an empty array, but it's always an array.
In a component, use “v” to access the collection of attributes. For example, {!v.body} outputs the body of the component.
Setting the Body Content
To set the body attribute in a component, add free markup within the <aura:component> tag. For example:
1<aura:component>
2 <!--START BODY-->
3 <div>Body part</div>
4 <lightning:button label="Push Me" onclick="{!c.doSomething}"/>
5 <!--END BODY-->
6</aura:component>To set the value of an inherited attribute, use the <aura:set> tag. Setting the body content is equivalent to wrapping that free markup inside <aura:set attribute="body">. Since the body attribute has this special behavior, you can omit <aura:set attribute="body">.
The previous sample is a shortcut for this markup. We recommend the less verbose syntax in the previous sample.
1<aura:component>
2 <aura:set attribute="body">
3 <!--START BODY-->
4 <div>Body part</div>
5 <lightning:button label="Push Me" onclick="{!c.doSomething}"/>
6 <!--END BODY-->
7 </aura:set>
8</aura:component>The same logic applies when you use any component that has a body attribute, not just <aura:component>. For example:
1<lightning:tabset>
2 <lightning:tab label="Tab 1">
3 Hello world!
4 </lightning:tab>
5</lightning:tabset>This is a shortcut for:
1<lightning:tabset>
2 <lightning:tab label="Tab 1">
3 <aura:set attribute="body">
4 Hello World!
5 </aura:set>
6 </lightning:tab>
7</lightning:tabset>Accessing the Component Body
To access a component body in JavaScript, use component.get("v.body").