6.85.  < rich:tree >

6.85.1. Description

The component is designed for hierarchical data presentation and is applied for building a tree structure with a drag-and-drop capability.

Expanded <rich:tree> with child elements

Figure 6.248. Expanded <rich:tree> with child elements


6.85.2. Key Features

  • Highly customizable look-and-feel

  • Built-in drag and drop capability, than enable relocating tree nodes within the tree

  • Built-in Ajax processing

  • Possibility to define a visual representation by node type

  • Support of several root elements in a tree

Table 6.465. rich : tree attributes

Attribute NameDescription
acceptCursorsList of comma separated cursors that indicates when acceptable draggable over dropzone
acceptedTypesA list of drag zones types, which elements are accepted by a drop zone
adviseNodeOpenedMethodBinding pointing at a method accepting an org.richfaces.component.UITree with return of java.lang.Boolean type. If returned value is: java.lang.Boolean. TRUE, a particular treeNode is expanded; java.lang.Boolean.FALSE, a particular treeNode is collapsed; null, a particular treeNode saves the current state
adviseNodeSelectedMethodBinding pointing at a method accepting an org.richfaces.component.UITree with return of java.lang.Boolean type. If returned value is: java.lang.Boolean. TRUE, a particular treeNode is selected; java.lang.Boolean.FALSE, a particular treeNode is unselected; null, a particular treeNode saves the current state
ajaxSingleif "true", submits ONLY one field/link, instead of all form controls
ajaxSubmitSelectionIf "true", an Ajax request to be submit when selecting node. Default value is "false".
bindingThe attribute takes a value-binding expression for a component property of a backing bean
bypassUpdatesIf "true", after process validations phase it skips updates of model beans on a force render response. It can be used for validating components input
changeExpandListenerListener called on expand/collapse event on the node
componentStateIt defines EL-binding for a component state for saving or redefinition
cursorTypeMappingMapping between drop types and acceptable cursors
dataSerialized (on default with JSON) data passed on the client by a developer on AJAX request. It's accessible via "data.foo" syntax
dragIndicatorId of a component that is used as drag pointer during the drag operation
dragListenerMethodBinding representing an action listener method that will be notified after drag operation
dragTypeA drag zone type that is used for zone definition, which elements can be accepted by a drop zone
dragValueData to be sent to the drop zone after a drop event. Default value is "getRowKey()".
dropListenerMethodBinding representing an action listener method that will be notified after drop operation
dropValueData to be processed after a drop event. Default value is "getRowKey()".
eventsQueueName of requests queue to avoid send next request before complete other from same event. Can be used to reduce number of requests of frequently events (key press, mouse move etc.)
focusid of element to set focus after request completed on client side
grabbingCursorsList of comma separated cursors that indicates when you has grabbed something
grabCursorsList of comma separated cursors that indicates when you can grab and drag an object
highlightedClassCorresponds to the HTML class attribute. Applied to highlighted node
iconThe icon for node
iconCollapsedThe icon for collapsed node
iconExpandedThe icon for expanded node
iconLeafAn icon for component leaves
idEvery component may have a unique id that is automatically created if omitted
ignoreDupResponsesAttribute allows to ignore an Ajax Response produced by a request if the newest 'similar' request is in a queue already. ignoreDupResponses="true" does not cancel the request while it is processed on the server, but just allows to avoid unnecessary updates on the client side if the response isn't actual now
immediateA flag indicating that this component value must be converted and validated immediately (during an Apply Request Values phase), rather than waiting until a Process Validations phase
limitToListIf "true", updates on client side ONLY elements from this 'reRender' property. If "false" (default) updates all rendered by ajax region components
nodeFaceNode face facet name
nodeSelectListenerMethodBinding representing an action listener method that will be notified after selection of node.
onbeforedomupdateJavaScript code for call before DOM has been updated on client side
onclickHTML: a script expression; a pointer button is clicked
oncollapseHTML: script expression to invoke on node collapsing
oncompleteJavaScript code for call after request completed on client side
ondblclickHTML: a script expression; a pointer button is double-clicked
ondragendA JavaScript event handler called after a drag operation
ondragenterA JavaScript event handler called on enter draggable object to zone
ondragexitA JavaScript event handler called after a drag object leaves zone
ondragstartA JavaScript event handler called before drag operation
ondropIt's an event that is called when something is dropped on a drop zone
ondropendA JavaScript handler for event fired on a drop even the drop for a given type is not available
ondropoutA JavaScript event handler called after a out operation
ondropoverA JavaScript event handler called after a drop operation
onexpandHTML: script expression to invoke on node expansion
onkeydownHTML: a script expression; a key is pressed down
onkeypressHTML: a script expression; a key is pressed and released
onkeyupHTML: a script expression; a key is released
onmousedownHTML: script expression; a pointer button is pressed down
onmousemoveHTML: a script expression; a pointer is moved within
onmouseoutHTML: a script expression; a pointer is moved away
onmouseoverHTML: a script expression; a pointer is moved onto
onmouseupHTML: script expression; a pointer button is released
onselectedHTML: script expression to invoke on node selection
preserveDataInRequestIf "true", data is preserved in a request. Default value is "true".
preserveModelPossible values are "state", "request", "none". Default value is "request"
processId['s] (in format of call UIComponent.findComponent()) of components, processed at the phases 2-5 in case of AjaxRequest caused by this component. Can be single id, comma-separated list of Id's, or EL Expression with array or Collection
rejectCursorsList of comma separated cursors that indicates when rejectable draggable over dropzone
renderedIf "false", this component is not rendered
requestDelayAttribute defines the time (in ms.) that the request will be wait in the queue before it is ready to send. When the delay time is over, the request will be sent to the server or removed if the newest 'similar' request is in a queue already
reRenderId['s] (in format of call UIComponent.findComponent()) of components, rendered in case of AjaxRequest caused by this component. Can be single id, comma-separated list of Id's, or EL Expression with array or Collection
rowKeyVarThe attribute provides access to a row key in a Request scope
selectedClassCorresponds to the HTML class attribute. Applied to selected node
showConnectingLinesIf "true", connecting lines are show
stateAdvisorValueBinding pointing at instance of class implementing org.richfaces.component.state.TreeStateAdvisor interface.
stateVarThe attribute provides access to a component state on the client side
statusID (in format of call UIComponent.findComponent()) of Request status component
styleCSS style(s) is/are to be applied when this component is rendered
styleClassCorresponds to the HTML class attribute
switchTypeTree switch algorithm: "client", "server", "ajax"
timeoutResponse waiting time on a particular request. If a response is not received during this time, the request is aborted
toggleOnClickIf "false" do not toggle node state on click. If "true", than node will be toggles on click on ether node content, or node icon. Default value is "false".
treeNodeVarThe attribute provides access to a TreeNode instance in a Request scope
typeMappingMap between a draggable type and an indicator name on zone. it's defined with the pair (drag type:indicator name))
valueThe current value for this component
varAttribute contains a name providing an access to data defined with value

Table 6.466. Component identification parameters

NameValue
component-typeorg.richfaces.Tree
component-classorg.richfaces.component.html.HtmlTree
component-familyorg.richfaces.Tree
renderer-typeorg.richfaces.TreeRenderer
tag-classorg.richfaces.taglib.TreeTag

6.85.3. Creating the Component with a Page Tag

There are two ways to set up a tree: 1) with <rich:recursiveTreeNodesAdaptor> or <rich:treeNodesAdaptor> 2) and without them. The first method allows to omit "value" and "var" attributes definition as follows:

Example:


...
<rich:tree>
    <rich:recursiveTreeNodesAdaptor roots="#{fileSystemBean.sourceRoots}" var="item" nodes="#{item.nodes}" />
</rich:tree>
...

The second way requires defining some attributes, as it's shown in the example:

Example:


...
<rich:tree value="#{library.data}" var="item" >
    <rich:treeNode  icon="/images/tree/singer.png" >
        <h:outputText value="#{item.name}" />
    </rich:treeNode>
    ...
</rich:tree>
...

6.85.4. Creating the Component Dynamically Using Java

Example:


import org.richfaces.component.html.HtmlTree;
...
HtmlTree myTree = new HtmlTree();
...

6.85.5. Details of Usage

As it has been mentioned above the <rich:tree> component allows rendering any tree-like data model.

The component interacts with data model via "TreeNode" interface (org.richfaces.model.TreeNode) that is used for tree nodes representation. The "value" attribute of the <rich:tree> component contains a nodes structure defined in a bean property. The property keeps a structure of objects that implements "TreeNode" interface.

<rich:treeNode> has a property "data" (see org.richfaces.model.TreeNode). Data contained in the property is placed in a request scope variable, which name is defined with "var" attribute for the <rich:tree> component.

You can develop and use your own pattern of the "TreeNode" interface or use a default implementation, which is defined with a default class "TreeNodeImpl" (org.richfaces.model.TreeNodeImpl).

There is a "XmlTreeDataBuilder" class (org.richfaces.component.xml.XmlTreeDataBuilder) that allows transforming XML into structures of objects containing "XmlNodeData" (org.richfaces.component.xml.XmlNodeData) instances as data, which could be represented by the <rich:tree> component.

It's possible to define a visual representation of a node data model (to define a node icon) and its behavior in correspondence with the data contained in this node (with a value of the "var" attribute). The node behavior is defined by the components nested into the <rich:treeNode> (e.g. links or buttons). For these purposes you should use "nodeFace" attribute. For each tree node a value of "nodeFace" attribute is evaluated and <rich:treeNode> with a value of "type" attribute equal to a value of "nodeFace" is used for node representation. See an example below.

Example:


...
<h:form>    
    <rich:tree style="width:300px" value="#{library.data}" var="item" nodeFace="#{item.type}">
        <rich:treeNode type="artist" iconLeaf="/images/tree/singer.png" icon="/images/tree/singer.png">
            <h:outputText value="#{item.name}" />
        </rich:treeNode>
        <rich:treeNode type="album" iconLeaf="/images/tree/disc.png" icon="/images/tree/disc.png">
            <h:outputText value="#{item.title}" />
        </rich:treeNode>
        <rich:treeNode type="song" iconLeaf="/images/tree/song.png" icon="/images/tree/song.png">
            <h:outputText value="#{item.title}" />
        </rich:treeNode>
    </rich:tree>
</h:form>
...

This is a result:

The "nodeFace" attribute usage

Figure 6.249. The "nodeFace" attribute usage


In the example above, when each node of data model is processed, data contained in the "data" property of "TreeNode" interface is assigned to a request scope variable, which name is defined with "var" attribute. The value of the "nodeFace" attribute is evaluated in correspondence with the data assigned to the "var" attribute. The corresponding <rich:treeNode> component (with a value of "type" attribute equal to a value of "nodeFace" ) is used for the node representation. For example, during data model processing, an object with a name "Chris Rea" was inserted in the "var" attribute. Then the value of "nodeFace" attribute was evaluated as "artist". Thus, for the node representation the <rich:treeNode> with "type" equal to "artist" was used.

You can also assign an EL-expression as value of the "nodeFace" attribute. See an example below:

Example:



nodeFace="#{data.name != 'param-value' ? 'artist' : 'album'}" 
 

There are some essential points in a "nodeFace" attribute usage: you need to define notions for typeless and a default nodes.

The typeless node is the first <rich:treeNode> component (from all children nodes nested to the <rich:tree> component) with not defined "type" attribute and defined "rendered" attribute. The typeless node is used for representation when "nodeFace" attribute is null.

Default node has the following interior presentation:

Example:


...
<h:outputText value="#{varAttributeName}">
...

"varAttributeName" is a value for "var" attribute.

Default node is used in the following cases:

  • "nodeFace" attribute is defined, but its value isn't equal to any "type" attribute value from all children nodes;

  • "nodeFace" attribute is defined and its value is equal to a value of some "type" attribute from all children nodes , but the value of "rendered" attribute for this node is "false".

There is also one thing that has to be remembered using "type" and "rendered" attributes: it's possible to define several <rich:treeNode> components with equal values of "type" attribute and different values of "rendered" attribute. It provides a possibility to define different representation styles for the same node types. In the example with artists and their albums (see above) it's possible to represent albums that are available for sale and albums that are not available. Please study the example below:

Example:


...
<h:form>    
    <rich:tree style="width:300px" value="#{library.data}" var="item" nodeFace="#{item.type}">
    ...
        <rich:treeNode type="album" iconLeaf="/images/tree/album.gif" icon="/images/tree/album.gif"
                      rendered="#{item.exist}">
            <h:outputText value="#{item.name}" />
        </rich:treeNode>
        <rich:treeNode type="album" iconLeaf="/images/tree/album_absent.gif" icon="/images/tree/album_absent.gif"
                      rendered="#{not item.exist}">
            <h:outputText value="#{item.name}" />
        </rich:treeNode>
    ...
    </rich:tree>
</h:form>
...

This is a result of the code:

The "type" and the "rendered" attributes usage

Figure 6.250. The "type" and the "rendered" attributes usage


In the example the <rich:treeNode> components has equal values of the "type" attribute. Depending on value of the "rendered" attribute the corresponding <rich:treeNode> component is selected for node representation. If an album is available for sale the value of the "rendered" for the first <rich:treeNode> component is "true", for the second one is "false". Thus, the first <rich:treeNode> is selected for node representation.

Tree node can be run in tree modes. Modes can be specified with "switchType" attribute for <rich:tree> component.

  • Ajax (default value) - Ajax submission is used performing the functionality. Note, that for collapse/expand operations an Ajax request is sent to the server and it can cause a short delay.

  • Server - regular form of submission request is used.

  • Client – all operations are performed totally on the client; no interaction with a server is involved. Full page content is reloaded after every action.

The "icon" , "iconCollapsed" , "iconExpanded" , "iconLeaf" attributes set the icons' images for the component. You can also define icons using facets with the same names. If the facets are defined, the corresponding attributes are ignored and facets' content is used as icons. By default the width of a rendered facet area is 16px.

Example:


...
<rich:tree value="#{library.data}" var="item">
    ...
    <f:facet name="icon">
        <h:graphicImage value="/images/tree/singer.png "/>
    </f:facet>
    <f:facet name="iconCollapsed">
        <h:graphicImage value="/images/tree/singer.png " />
    </f:facet>      
    <f:facet name="iconExpanded">
        <h:graphicImage value="/images/tree/singer.png " />
    </f:facet>
    <f:facet name="iconLeaf">
        <h:graphicImage value="/images/tree/song.png " />
    </f:facet>
    ...
</rich:tree>
...

The <rich: tree> component can be used together with <rich: treeNodeAdaptor> . In this case there is no need to specify the attributes "value" and "var" . Besides, visual representation shouldn't be defined right in the tree. In this case a <rich: tree> tag is applied mainly for defining common attributes such as "ajaxSubmitSelection" etc.

Information about the "process" attribute usage you can find here.

6.85.6. Built-In Drag and Drop

The <rich: tree> component functionality provides a built-in support for Drag and Drop operations. The main usage principles are similar to RichFaces DnD wrapper components. Hence, to get additional information on the issue, read the corresponding chapters:"rich:dndParam", "rich:dragSupport", "rich:dragIndicator", "rich:dropSupport". Since treeNodescan be assigned as Drag, Drop or Drag-and-Drop elements, a tree can include the following groups of attributes.

Table 6.467. Drag group

Attribute NameDescription
dragValueElement value drag passed into processing after a Drop event
dragListenerA listener that processes a Drag event
dragIndicatorId of a component that is used as a drag pointer during the drag operation
dragTypeDefines a drag zone type that is used for definition of a dragged element, which can be accepted by a drop zone

Table 6.468. Drop group

Attribute NameDescription
dropValueElement value drop passed into processing after Drop events
dropListenerA listener that processes a Drop event.
acceptedTypesDrag zone names are allowed to be processed with a Drop zone
typeMappingDrag zones names mapping on the corresponding drop zone parameters

Please see an example below.

Example:


...
<h:form>    
    <rich:tree dragIndicator=":treeDragIndicator" dropListener="#{libraryAjaxTree.processDrop}" style="width:300px" value="#{libraryAjaxTree.data}" var="item" nodeFace="#{item.type}">
        <rich:treeNode type="artist" acceptedTypes="album" iconLeaf="/images/tree/group.png" icon="/images/tree/group.png">
            <h:outputText value="#{item.name}" />
        </rich:treeNode>
        <rich:treeNode type="album" dragType="album" acceptedTypes="song" iconLeaf="/images/tree/cd.png" icon="/images/tree/cd.png">
            <h:outputText value="#{item.title}" />
            <rich:dndParam name="label" type="drag" value="Album: #{item.title}" />
        </rich:treeNode>
        <rich:treeNode type="song" dragType="song" iconLeaf="/images/tree/music.png" icon="/images/tree/music.png">
            <h:outputText value="#{item.title}" />
            <rich:dndParam name="label" type="drag" value="Song: #{item.title}" />
        </rich:treeNode>
    </rich:tree>
</h:form>
...

In the shown example a song from one album can be dragged into another because attribute "acceptedTypes" ="song" defined in the second treeNode with "type" ="album". Its value is equal to the value of the "type" attribute defined in the third treeNode (see picture below). An album can be also dragged into treeNode with "type" ="artist" property.

DnD operations

Figure 6.251. DnD operations


6.85.7. Events handling

Listeners classes that process events on the server side are defined with the help of:

  • changeExpandListener processes expand/collapse event of a treeNode

  • dropListener processes a Drop event

  • dragListener processes a Drag event

  • nodeSelectListener is called during request sending on a node selecting event (if request sending on this event is defined)

Listener methods can be defined using the following attributes or using nested tags.

Client event attributes are:

  • onexpand is a script expression to invoke when a node is expanded

  • oncollapse is a script expression to invoke when a node is collapsed

  • ondragexit is a script expression to invoke when an element passing out from a tree zone

  • ondragstart is a script expression to invoke when dragging starts

  • ondragend is a script expression to invoke when dragging ends (a drop event)

  • ondragenter is a script expression to invoke when a dragged element appears on a tree

They can be used to add some JavaScript effects.

Standart HTML event attributes like "onclick" , "onmousedown" , "onmouseover" etc. can be also used. Event handlers of a <rich:tree> component capture events occured on any tree part. But event handlers of treeNode capture events occured on treeNode only, except for children events.

6.85.8. Look-and-Feel Customization

For skinnability implementation, the components use a style class redefinition method. Default style classes are mapped on skin parameters.

There are two ways to redefine the appearance of all <rich:tree> components at once:

  • Redefine the corresponding skin parameters

  • Add to your style sheets style classes used by a <rich:tree> component

6.85.9. Skin Parameters Redefinition:

There is only one skin parameter for <rich:tree> . As it's a wrapper component for <rich:treeNode> components, look and feel customization is described in the corresponding section.

Table 6.469. Skin parameters for a wrapper element

Skin parametersCSS properties
overAllBackgroundbackground-color

6.85.10. Definition of Custom Style Classes

Table 6.470. Classes names that define a component appearance

Class nameDescription
rich-treeDefines styles for a wrapper <div> element of a tree

In order to redefine styles for all <rich:tree> components on a page using CSS, it's enough to create classes with the same names (possible classes could be found in the table above) and define necessary properties in them. An example is placed below:

Example:


...
 
.rich-tree{
    
font-weight:bold;
}
...

This is a result:

Redefinition styles with predefined classes

Figure 6.252. Redefinition styles with predefined classes


In the example a tree font weight was changed to bold.

Also it's possible to change styles of a particular <rich:tree> component. In this case you should create own style classes and use them in corresponding <rich:tree> styleClass attributes. An example is placed below:

Example:


...
.myClass{
    
font-weight:bold;
}
...

The "highlightedClass" attribute for <rich:tree> is defined as it’s shown in the example below:

Example:


...
<rich:tree ... styleClass="myClass"/>
...

This is a result:

Redefinition styles with own classes and styleClass attributes

Figure 6.253. Redefinition styles with own classes and styleClass attributes


As it's shown on the picture above, font weight of highlighted text node of a tree was changed to bold.

6.85.11. Relevant Resources Links

Here you can see the example of <rich:tree> usage and sources for the given example.

How to Expand/Collapse Tree Nodes from code, see here.