< Jewel Components list

Jewel Container

Reference

Available since version 0.9.4.

Class Extends Implements
org.apache.royale.jewel.Container Jewel ContainerBase org.apache.royale.core.IMXMLDocument

Note: This component is currently only available for JavaScript.

Overview

The Jewel Container class is a container that adds up to the features already provided by Jewel Group.

The position and size of the children are determined by BasicLayout while the size of a Container can either be determined by its children or by specifying an exact size in pixels or as a percentage of the parent element. You can swap the layout for any other one available making children arrange in different ways (i.e: horizontal, vertical,…)

Container clip content by default thanks to its Viewport bead. This bead can also manage clipping trough clipContent property. To add scrolling functionality Viewport bead can be changed by ScrollingViewport.

Other Container feature are View States to provide state management to show diferent parts of the interface to the user.

Finally Container can add elements directly to the strand (throught strandChildren property) instead to its view content unlike the addElement() APIs which place children into the contentView.

While the container is relatively lightweight, it should generally not be used as the base class for other controls, even if those controls are composed of children. That’s because the fundamental API of Container is to support an arbitrary set of children, and most controls only support a specific set of children.

Example of use

In MXML declare a Container like this:

<j:Container width="200" height="200" className="wrapper">
    <j:Button text="Origin"/>
    <j:Button text="x:30,y:30" x="30" y="30"/>
    <j:Button text="x:60,y:60" x="60" y="60"/>
    <j:Button text="bottom/right" style="bottom:0;right:0"/>
</j:Container>

In ActionScript we can do the same in the following way:

var container:Container = new Container();
// add a button to the Container
var button:Button = new Button();
container.addElement(button);
// add the Container to the parent
parent.addElement(container);

where parent is the container where the control will be added.

Relevant Properties and Methods

Check the Reference of org.apache.royale.jewel.Container for a more detailed list of properties and methods.

Properties

PROPERTY Type Description
currentState String The name of the current state.
numElements int The number of element children that can be laid out.
mxmlContent Array The array of childs for this container. Is the DefaultProperty.
states Array The array of view states. These should be instances of org.apache.royale.states.State
strandChildren IParent An object to access the immediate children of the strand.

Methods

Method Parameters Description
addElement c(IChild), dispatchEvent(Boolean=true) Add a component to the parent.
addElementAt c(IChild), index(int), dispatchEvent(Boolean=true) Add a component to the parent at the specified index.
getElementIndex c(IChild) Gets the index of this subcomponent.
getElementAt index(int) Get a component from the parent at specified index.
removeElement c(IChild), dispatchEvent(Boolean=true) Remove a component from the parent.

Relevant Events

The most important event is initComplete, which indicates that the initialization of the container is complete.

Is needed when some action coded in a callback function need to be triggered as the container is ready to use after initialization.

You can attach callback listeners to the initComplete event in MXML as follows:

<j:Container initComplete="initCompleteHandler(event)"/>

the initComplete event will use the initCompleteHandler callback function you provide in ActionScript:

<fx:Script>
    <![CDATA[      
        private function initCompleteHandler(event:Event):void {
            trace("Container is ready!");
        }
    ]]>
</fx:Script>

When the container is initialized the message “Container is ready!” appears in the console log.

In ActionScript we can add an event handler this way:

var c:Container = new Container();
c.addEventListener('initComplete', initCompleteHandler);
parent.addElement(c);

Relevant Beads

Bead Type Implementation Description
ContainerView org.apache.royale.core.IBeadView This is the default view bead.
BasicLayout org.apache.royale.core.IBeadLayout This is the default layout bead.

Optional Beads

Bead Type Implementation Description
ContainerDataBinding org.apache.royale.binding.DataBindingBase Provide binding capabilities to the container.

Common Beads

Jewel Container can use any of the layout beads available in Jewel library. Also you can check Related controls section to see some preconfigured containers with specific layouts.

More examples

Other useful Jewel containers components are: