I'm using PrimeFaces and I have a line:
<p:ajax update="toUpdate">
the problem is, that this ID not always exists on the page.
( the page is dynamic and sometimes it contains a part that have this specific ID and sometimes not)
When it exists, it works great, but when the ID doesn't exist, the component crash - (probably it's some validation issue)
How can I fix it?
Is it a well known issue?
Thanks!
You need to provide an always rendered component to update, for example:
<p:ajax update="toUpdate">
<h:panelGroup id="toUpdate">
<p:dataTable id="tableID" rendered="#{bean.someCondition>"...
</h:panelGroup>
So, if you have a component that can be o or not visible, do not use it for update, because can be out of components tree. Instead, use a component (container) that your are sure that be rendered and present in the components tree.
Try this code
<f:ajax render="toUpdate">
<h:outputText id="toUpdate">
<!-- do something -->
</h:outputText>
Related
The following code is inspired from PrimeFaces DataGrid + DataTable Tutorials and put into a <p:tab> of a <p:tabView> residing in a <p:layoutUnit> of a <p:layout>. Here is the inner part of the code (starting from p:tab component); the outer part is trivial.
<p:tabView id="tabs">
<p:tab id="search" title="Search">
<h:form id="insTable">
<p:dataTable id="table" var="lndInstrument" value="#{instrumentBean.instruments}">
<p:column>
<p:commandLink id="select" update="insTable:display" oncomplete="dlg.show()">
<f:setPropertyActionListener value="#{lndInstrument}"
target="#{instrumentBean.selectedInstrument}" />
<h:outputText value="#{lndInstrument.name}" />
</p:commandLink>
</p:column>
</p:dataTable>
<p:dialog id="dlg" modal="true" widgetVar="dlg">
<h:panelGrid id="display">
<h:outputText value="Name:" />
<h:outputText value="#{instrumentBean.selectedInstrument.name}" />
</h:panelGrid>
</p:dialog>
</h:form>
</p:tab>
</p:tabView>
When I click the <p:commandLink>, the code stops working and gives the message:
Cannot find component with expression "insTable:display" referenced from "tabs:insTable:select".
When I try the same using <f:ajax>, then it fails with a different message basically telling the same:
<f:ajax> contains an unknown id "insTable:display" cannot locate it in the context of the component "tabs:insTable:select"
When it happens during another Ajax postback and the JSF project stage is set to Development, then it fails with a JavaScript alert with the message:
malformedXML: During update: insTable:display not found
How is this caused and how can I solve it?
Look in HTML output for actual client ID
You need to look in the generated HTML output to find out the right client ID. Open the page in browser, do a rightclick and View Source. Locate the HTML representation of the JSF component of interest and take its id as client ID. You can use it in an absolute or relative way depending on the current naming container. See following chapter.
Note: if it happens to contain iteration index like :0:, :1:, etc (because it's inside an iterating component), then you need to realize that updating a specific iteration round is not always supported. See bottom of answer for more detail on that.
Memorize NamingContainer components and always give them a fixed ID
If a component which you'd like to reference by ajax process/execute/update/render is inside the same NamingContainer parent, then just reference its own ID.
<h:form id="form">
<p:commandLink update="result"> <!-- OK! -->
<h:panelGroup id="result" />
</h:form>
If it's not inside the same NamingContainer, then you need to reference it using an absolute client ID. An absolute client ID starts with the NamingContainer separator character, which is by default :.
<h:form id="form">
<p:commandLink update="result"> <!-- FAIL! -->
</h:form>
<h:panelGroup id="result" />
<h:form id="form">
<p:commandLink update=":result"> <!-- OK! -->
</h:form>
<h:panelGroup id="result" />
<h:form id="form">
<p:commandLink update=":result"> <!-- FAIL! -->
</h:form>
<h:form id="otherform">
<h:panelGroup id="result" />
</h:form>
<h:form id="form">
<p:commandLink update=":otherform:result"> <!-- OK! -->
</h:form>
<h:form id="otherform">
<h:panelGroup id="result" />
</h:form>
NamingContainer components are for example <h:form>, <h:dataTable>, <p:tabView>, <cc:implementation> (thus, all composite components), etc. You recognize them easily by looking at the generated HTML output, their ID will be prepended to the generated client ID of all child components. Note that when they don't have a fixed ID, then JSF will use an autogenerated ID in j_idXXX format. You should absolutely avoid that by giving them a fixed ID. The OmniFaces NoAutoGeneratedIdViewHandler may be helpful in this during development.
If you know to find the javadoc of the UIComponent in question, then you can also just check in there whether it implements the NamingContainer interface or not. For example, the HtmlForm (the UIComponent behind <h:form> tag) shows it implements NamingContainer, but the HtmlPanelGroup (the UIComponent behind <h:panelGroup> tag) does not show it, so it does not implement NamingContainer. Here is the javadoc of all standard components and here is the javadoc of PrimeFaces.
Solving your problem
So in your case of:
<p:tabView id="tabs"><!-- This is a NamingContainer -->
<p:tab id="search"><!-- This is NOT a NamingContainer -->
<h:form id="insTable"><!-- This is a NamingContainer -->
<p:dialog id="dlg"><!-- This is NOT a NamingContainer -->
<h:panelGrid id="display">
The generated HTML output of <h:panelGrid id="display"> looks like this:
<table id="tabs:insTable:display">
You need to take exactly that id as client ID and then prefix with : for usage in update:
<p:commandLink update=":tabs:insTable:display">
Referencing outside include/tagfile/composite
If this command link is inside an include/tagfile, and the target is outside it, and thus you don't necessarily know the ID of the naming container parent of the current naming container, then you can dynamically reference it via UIComponent#getNamingContainer() like so:
<p:commandLink update=":#{component.namingContainer.parent.namingContainer.clientId}:display">
Or, if this command link is inside a composite component and the target is outside it:
<p:commandLink update=":#{cc.parent.namingContainer.clientId}:display">
Or, if both the command link and target are inside same composite component:
<p:commandLink update=":#{cc.clientId}:display">
See also Get id of parent naming container in template for in render / update attribute
How does it work under the covers
This all is specified as "search expression" in the UIComponent#findComponent() javadoc:
A search expression consists of either an identifier (which is matched exactly against the id property of a UIComponent, or a series of such identifiers linked by the UINamingContainer#getSeparatorChar character value. The search algorithm should operates as follows, though alternate alogrithms may be used as long as the end result is the same:
Identify the UIComponent that will be the base for searching, by stopping as soon as one of the following conditions is met:
If the search expression begins with the the separator character (called an "absolute" search expression), the base will be the root UIComponent of the component tree. The leading separator character will be stripped off, and the remainder of the search expression will be treated as a "relative" search expression as described below.
Otherwise, if this UIComponent is a NamingContainer it will serve as the basis.
Otherwise, search up the parents of this component. If a NamingContainer is encountered, it will be the base.
Otherwise (if no NamingContainer is encountered) the root UIComponent will be the base.
The search expression (possibly modified in the previous step) is now a "relative" search expression that will be used to locate the component (if any) that has an id that matches, within the scope of the base component. The match is performed as follows:
If the search expression is a simple identifier, this value is compared to the id property, and then recursively through the facets and children of the base UIComponent (except that if a descendant NamingContainer is found, its own facets and children are not searched).
If the search expression includes more than one identifier separated by the separator character, the first identifier is used to locate a NamingContainer by the rules in the previous bullet point. Then, the findComponent() method of this NamingContainer will be called, passing the remainder of the search expression.
Note that PrimeFaces also adheres the JSF spec, but RichFaces uses "some additional exceptions".
"reRender" uses UIComponent.findComponent() algorithm (with some additional exceptions) to find the component in the component tree.
Those additional exceptions are nowhere in detail described, but it's known that relative component IDs (i.e. those not starting with :) are not only searched in the context of the closest parent NamingContainer, but also in all other NamingContainer components in the same view (which is a relatively expensive job by the way).
Never use prependId="false"
If this all still doesn't work, then verify if you aren't using <h:form prependId="false">. This will fail during processing the ajax submit and render. See also this related question: UIForm with prependId="false" breaks <f:ajax render>.
Referencing specific iteration round of iterating components
It was for long time not possible to reference a specific iterated item in iterating components like <ui:repeat> and <h:dataTable> like so:
<h:form id="form">
<ui:repeat id="list" value="#{['one','two','three']}" var="item">
<h:outputText id="item" value="#{item}" /><br/>
</ui:repeat>
<h:commandButton value="Update second item">
<f:ajax render=":form:list:1:item" />
</h:commandButton>
</h:form>
However, since Mojarra 2.2.5 the <f:ajax> started to support it (it simply stopped validating it; thus you would never face the in the question mentioned exception anymore; another enhancement fix is planned for that later).
This only doesn't work yet in current MyFaces 2.2.7 and PrimeFaces 5.2 versions. The support might come in the future versions. In the meanwhile, your best bet is to update the iterating component itself, or a parent in case it doesn't render HTML, like <ui:repeat>.
When using PrimeFaces, consider Search Expressions or Selectors
PrimeFaces Search Expressions allows you to reference components via JSF component tree search expressions. JSF has several builtin:
#this: current component
#form: parent UIForm
#all: entire document
#none: nothing
PrimeFaces has enhanced this with new keywords and composite expression support:
#parent: parent component
#namingcontainer: parent UINamingContainer
#widgetVar(name): component as identified by given widgetVar
You can also mix those keywords in composite expressions such as #form:#parent, #this:#parent:#parent, etc.
PrimeFaces Selectors (PFS) as in #(.someclass) allows you to reference components via jQuery CSS selector syntax. E.g. referencing components having all a common style class in the HTML output. This is particularly helpful in case you need to reference "a lot of" components. This only prerequires that the target components have all a client ID in the HTML output (fixed or autogenerated, doesn't matter). See also How do PrimeFaces Selectors as in update="#(.myClass)" work?
first of all: as far as i know placing dialog inside a tabview is a bad practice... you better take it out...
and now to your question:
sorry, took me some time to get what exactly you wanted to implement,
did at my web app myself just now, and it works
as I sayed before place the p:dialog out side the `p:tabView ,
leave the p:dialog as you initially suggested :
<p:dialog modal="true" widgetVar="dlg">
<h:panelGrid id="display">
<h:outputText value="Name:" />
<h:outputText value="#{instrumentBean.selectedInstrument.name}" />
</h:panelGrid>
</p:dialog>
and the p:commandlink should look like this (all i did is to change the update attribute)
<p:commandLink update="display" oncomplete="dlg.show()">
<f:setPropertyActionListener value="#{lndInstrument}"
target="#{instrumentBean.selectedInstrument}" />
<h:outputText value="#{lndInstrument.name}" />
</p:commandLink>
the same works in my web app, and if it does not work for you , then i guess there is something wrong in your java bean code...
It's because the tab is a naming container aswell... your update should be update="Search:insTable:display" What you can do aswell is just place your dialog outside the form and still inside the tab then it would be: update="Search:display"
Please note that from PrimeFaces 10 and up, you are able to use observer and event.
This allows you to update components based on a custom event name, set by the #obs(event) keyword. For example:
<p:commandButton update="#obs(myEvent)"/>
<h:panelGroup>
<p:autoUpdate on="myEvent"/>
</h:panelGroup>
See:
https://www.primefaces.org/showcase/ui/ajax/observer.xhtml
I know this already has a great answer by BalusC but here is a little trick I use to get the container to tell me the correct clientId.
Remove the update on your component that is not working
Put a temporary component with a bogus update within the component you were trying to update
hit the page, the servlet exception error will tell you the correct client Id you need to reference.
Remove bogus component and put correct clientId in the original update
Here is code example as my words may not describe it best.
<p:tabView id="tabs">
<p:tab id="search" title="Search">
<h:form id="insTable">
<p:dataTable id="table" var="lndInstrument" value="#{instrumentBean.instruments}">
<p:column>
<p:commandLink id="select"
Remove the failing update within this component
oncomplete="dlg.show()">
<f:setPropertyActionListener value="#{lndInstrument}"
target="#{instrumentBean.selectedInstrument}" />
<h:outputText value="#{lndInstrument.name}" />
</p:commandLink>
</p:column>
</p:dataTable>
<p:dialog id="dlg" modal="true" widgetVar="dlg">
<h:panelGrid id="display">
Add a component within the component of the id you are trying to update using an update that will fail
<p:commandButton id="BogusButton" update="BogusUpdate"></p:commandButton>
<h:outputText value="Name:" />
<h:outputText value="#{instrumentBean.selectedInstrument.name}" />
</h:panelGrid>
</p:dialog>
</h:form>
</p:tab>
</p:tabView>
Hit this page and view the error.
The error is:
javax.servlet.ServletException: Cannot find component for expression "BogusUpdate" referenced from
tabs:insTable: BogusButton
So the correct clientId to use would then be the bold plus the id of the target container (display in this case)
tabs:insTable:display
Try change update="insTable:display" to update="display". I believe you cannot prefix the id with the form ID like that.
I have two problems which are closely related:
I need to update a form inside a tag inside ui:repeat from a dialog at the main page and cannot figure out how (because there are many tags in the ui:repeat and I need to update only one)
naming containers are messed up and lose their "index" when I use id in that form (in case of trying to determine the update path expression...)
reason I need this: updating the 'wholelist' (current situation) breaks all <p:calendar> inside the <p:dialog> somehow (no errors...) (the calendar overlay shows at the first time, but after updating the list it does not appear any more (must reload page again). Also I don't want to update 100 elements each time if only one can be changed
page.xhtml
<h:panelGroup id="wholelist">
<ui:repeat var="entry" value="#{bean.foundEntries}" id="repeatId">
<customTag:someTag entry="#{entry}" />
</ui:repeat>
</h:panelGroup>
...
<p:dialog widgetVar="dialog" id="dialog">
<p:calendar value="#{bean.date}" ... /> <!-- overlay pops up on select until the whole list is refreshed. after that it does not appear until page reload -->
<p:commandButton actionlistener="#{bean.saveSomething()}" update="#{bean.componentToUpdate WHICH DOES NOT WORK...}"/>
</p:dialog>
someTag.xhtml
and within the <customTag:someTag> (which is a tag because of multiple reuses) :
...
<h:form>
... display a lot of data which can be changed by the dialog...
<p:commandButton value="show edit dialog" onComplete="PF('dialog').show()" update=":dialog">
<f:setPropertyActionListener value="??? (#form does not work)" target="#{bean.componentToUpdate}" />
</p:commandButton>
</h:form>
First Question:
I need to refresh one single form from the dialog (=the dialog which needs to know which form I want to refresh, and I have no idea how to do so...)
And how can I get the update-logic working (pass the component to update to the bean so the dialog knows what to update or equal)?
Second Question:
why does JSF generate in case of not defining a id="..." to a naming container within a ui:repeat something like
repeatId:0:j_id_c0_6
repeatId:1:j_id_c0_6
repeatId:2:j_id_c0_6
and when I define a id to the form (<h:form id="formname">) something like
repeatId:formname
repeatId:formname
repeatId:formname
which causes duplicateId (because the lack of the "iterator-number" in the name)?
Does this make sense?
I have solved it; error was elsewhere: I have forgotten in an included tag file which caused the js warning (which broke the calendar).
many thanks
I'm asking how I can achieve updating a specific element of a loop?
e.g.
<h:form>
<ui:repeat var="element" value="#{bean.elements}" varStatus="status">
<h:outputtext value="#{element.text}" id="#{element.id}" />
<p:commandLink update="#{element.id}" >
<h:outputtext value="UpdateTextField #{element.id}" />
</p:commandLink>
</ui:repeat>
</h:form>
I know that status.index doen't work since its view-rendered. Also the "dynamic" index-setting also doen't work since its view-rendered... But how can i achieve that when the button is clicked, it updates (ajax) the outputtext? Is this only possible with c:forEach?
its ViewScoped and the form must be outside of the loop. otherwise i would solve it with update="#form", but here its not possible
thanks for any help!
Since both ui:repeat and c:forEach generate different dynamic Component Ids for the elements you can't Guarantee the update an individual Item out of all generated items from outside.
I think best approach for this kind of problem would be placing a h:panelGroup around ui:repeat or c:forEach itself and update the h:panelGroupitself.
I have a query here regarding the value given to the update attribute of the primefaces command button.
Here is a simple code. I have a simple xhtml page
<h:body>
<h:form id="main">
<p:growl id="maingrowl" showDetail="true"></p:growl>
<p:panelGrid id="mainpanel" columns="2">
<p:commandButton value="Ajax Submit" update="test" id="ajax"
actionListener="#{mytestBean.display}" />
</p:panelGrid>
<p:panelGrid id="test" rendered="#{mytestBean.show}" columns="1">
<h:inputText value="#{mytestBean.val1}" />
<h:inputText value="#{mytestBean.val2}" />
<p:commandButton value="value in" id="aj" update="test"
actionListener="#{mytestBean.displaysec}">
</p:commandButton>
</p:panelGrid>
</h:form>
</h:body>
Now, If I have to update the panelgrid "test" then in the first command button I have to provide the id "test" prefixed with ":main:" in the update attribute of the command button since that is the exact id in the HTML DOM as I find it in the view source in the browser. But, I was able to update even by given just "test" in the update attribute.
So my question here is when should I use the ":" in the id or is it mandatory or is there any pre defined rule to give the id's in the attribute?
Also, I am aware of the fact that the id given in the update attribute is through the UINamingContainer in which it is placed. Please pardon me if its trivial, I am really confused here.
Any help greatly appreciated.
Thank you.
If both components (the one to update and the one that triggers the update) are inside the same NamingContainer, the relative client id withoud the : is sufficient.
NamingContainers in jsf are all those components that prepend their own id to the client id of all child components, e.g. <h:form>, <h:dataTable> or <ui:repeat> (or to be more precise: all components that implement the javax.faces.component.NamingContainer interface).
If both components are not inside the same NamingContainer, you have to use the absolute id beginning with a : from the view root.
If you are interested in more detailed information I recommend reading the javadoc of the UIComponent#findComponent() method where the search algorithm is described.
Note that the : is the default character to separate segments of a clientId. You can change it with a context parameter in your web.xml.
The following code is inspired from PrimeFaces DataGrid + DataTable Tutorials and put into a <p:tab> of a <p:tabView> residing in a <p:layoutUnit> of a <p:layout>. Here is the inner part of the code (starting from p:tab component); the outer part is trivial.
<p:tabView id="tabs">
<p:tab id="search" title="Search">
<h:form id="insTable">
<p:dataTable id="table" var="lndInstrument" value="#{instrumentBean.instruments}">
<p:column>
<p:commandLink id="select" update="insTable:display" oncomplete="dlg.show()">
<f:setPropertyActionListener value="#{lndInstrument}"
target="#{instrumentBean.selectedInstrument}" />
<h:outputText value="#{lndInstrument.name}" />
</p:commandLink>
</p:column>
</p:dataTable>
<p:dialog id="dlg" modal="true" widgetVar="dlg">
<h:panelGrid id="display">
<h:outputText value="Name:" />
<h:outputText value="#{instrumentBean.selectedInstrument.name}" />
</h:panelGrid>
</p:dialog>
</h:form>
</p:tab>
</p:tabView>
When I click the <p:commandLink>, the code stops working and gives the message:
Cannot find component with expression "insTable:display" referenced from "tabs:insTable:select".
When I try the same using <f:ajax>, then it fails with a different message basically telling the same:
<f:ajax> contains an unknown id "insTable:display" cannot locate it in the context of the component "tabs:insTable:select"
When it happens during another Ajax postback and the JSF project stage is set to Development, then it fails with a JavaScript alert with the message:
malformedXML: During update: insTable:display not found
How is this caused and how can I solve it?
Look in HTML output for actual client ID
You need to look in the generated HTML output to find out the right client ID. Open the page in browser, do a rightclick and View Source. Locate the HTML representation of the JSF component of interest and take its id as client ID. You can use it in an absolute or relative way depending on the current naming container. See following chapter.
Note: if it happens to contain iteration index like :0:, :1:, etc (because it's inside an iterating component), then you need to realize that updating a specific iteration round is not always supported. See bottom of answer for more detail on that.
Memorize NamingContainer components and always give them a fixed ID
If a component which you'd like to reference by ajax process/execute/update/render is inside the same NamingContainer parent, then just reference its own ID.
<h:form id="form">
<p:commandLink update="result"> <!-- OK! -->
<h:panelGroup id="result" />
</h:form>
If it's not inside the same NamingContainer, then you need to reference it using an absolute client ID. An absolute client ID starts with the NamingContainer separator character, which is by default :.
<h:form id="form">
<p:commandLink update="result"> <!-- FAIL! -->
</h:form>
<h:panelGroup id="result" />
<h:form id="form">
<p:commandLink update=":result"> <!-- OK! -->
</h:form>
<h:panelGroup id="result" />
<h:form id="form">
<p:commandLink update=":result"> <!-- FAIL! -->
</h:form>
<h:form id="otherform">
<h:panelGroup id="result" />
</h:form>
<h:form id="form">
<p:commandLink update=":otherform:result"> <!-- OK! -->
</h:form>
<h:form id="otherform">
<h:panelGroup id="result" />
</h:form>
NamingContainer components are for example <h:form>, <h:dataTable>, <p:tabView>, <cc:implementation> (thus, all composite components), etc. You recognize them easily by looking at the generated HTML output, their ID will be prepended to the generated client ID of all child components. Note that when they don't have a fixed ID, then JSF will use an autogenerated ID in j_idXXX format. You should absolutely avoid that by giving them a fixed ID. The OmniFaces NoAutoGeneratedIdViewHandler may be helpful in this during development.
If you know to find the javadoc of the UIComponent in question, then you can also just check in there whether it implements the NamingContainer interface or not. For example, the HtmlForm (the UIComponent behind <h:form> tag) shows it implements NamingContainer, but the HtmlPanelGroup (the UIComponent behind <h:panelGroup> tag) does not show it, so it does not implement NamingContainer. Here is the javadoc of all standard components and here is the javadoc of PrimeFaces.
Solving your problem
So in your case of:
<p:tabView id="tabs"><!-- This is a NamingContainer -->
<p:tab id="search"><!-- This is NOT a NamingContainer -->
<h:form id="insTable"><!-- This is a NamingContainer -->
<p:dialog id="dlg"><!-- This is NOT a NamingContainer -->
<h:panelGrid id="display">
The generated HTML output of <h:panelGrid id="display"> looks like this:
<table id="tabs:insTable:display">
You need to take exactly that id as client ID and then prefix with : for usage in update:
<p:commandLink update=":tabs:insTable:display">
Referencing outside include/tagfile/composite
If this command link is inside an include/tagfile, and the target is outside it, and thus you don't necessarily know the ID of the naming container parent of the current naming container, then you can dynamically reference it via UIComponent#getNamingContainer() like so:
<p:commandLink update=":#{component.namingContainer.parent.namingContainer.clientId}:display">
Or, if this command link is inside a composite component and the target is outside it:
<p:commandLink update=":#{cc.parent.namingContainer.clientId}:display">
Or, if both the command link and target are inside same composite component:
<p:commandLink update=":#{cc.clientId}:display">
See also Get id of parent naming container in template for in render / update attribute
How does it work under the covers
This all is specified as "search expression" in the UIComponent#findComponent() javadoc:
A search expression consists of either an identifier (which is matched exactly against the id property of a UIComponent, or a series of such identifiers linked by the UINamingContainer#getSeparatorChar character value. The search algorithm should operates as follows, though alternate alogrithms may be used as long as the end result is the same:
Identify the UIComponent that will be the base for searching, by stopping as soon as one of the following conditions is met:
If the search expression begins with the the separator character (called an "absolute" search expression), the base will be the root UIComponent of the component tree. The leading separator character will be stripped off, and the remainder of the search expression will be treated as a "relative" search expression as described below.
Otherwise, if this UIComponent is a NamingContainer it will serve as the basis.
Otherwise, search up the parents of this component. If a NamingContainer is encountered, it will be the base.
Otherwise (if no NamingContainer is encountered) the root UIComponent will be the base.
The search expression (possibly modified in the previous step) is now a "relative" search expression that will be used to locate the component (if any) that has an id that matches, within the scope of the base component. The match is performed as follows:
If the search expression is a simple identifier, this value is compared to the id property, and then recursively through the facets and children of the base UIComponent (except that if a descendant NamingContainer is found, its own facets and children are not searched).
If the search expression includes more than one identifier separated by the separator character, the first identifier is used to locate a NamingContainer by the rules in the previous bullet point. Then, the findComponent() method of this NamingContainer will be called, passing the remainder of the search expression.
Note that PrimeFaces also adheres the JSF spec, but RichFaces uses "some additional exceptions".
"reRender" uses UIComponent.findComponent() algorithm (with some additional exceptions) to find the component in the component tree.
Those additional exceptions are nowhere in detail described, but it's known that relative component IDs (i.e. those not starting with :) are not only searched in the context of the closest parent NamingContainer, but also in all other NamingContainer components in the same view (which is a relatively expensive job by the way).
Never use prependId="false"
If this all still doesn't work, then verify if you aren't using <h:form prependId="false">. This will fail during processing the ajax submit and render. See also this related question: UIForm with prependId="false" breaks <f:ajax render>.
Referencing specific iteration round of iterating components
It was for long time not possible to reference a specific iterated item in iterating components like <ui:repeat> and <h:dataTable> like so:
<h:form id="form">
<ui:repeat id="list" value="#{['one','two','three']}" var="item">
<h:outputText id="item" value="#{item}" /><br/>
</ui:repeat>
<h:commandButton value="Update second item">
<f:ajax render=":form:list:1:item" />
</h:commandButton>
</h:form>
However, since Mojarra 2.2.5 the <f:ajax> started to support it (it simply stopped validating it; thus you would never face the in the question mentioned exception anymore; another enhancement fix is planned for that later).
This only doesn't work yet in current MyFaces 2.2.7 and PrimeFaces 5.2 versions. The support might come in the future versions. In the meanwhile, your best bet is to update the iterating component itself, or a parent in case it doesn't render HTML, like <ui:repeat>.
When using PrimeFaces, consider Search Expressions or Selectors
PrimeFaces Search Expressions allows you to reference components via JSF component tree search expressions. JSF has several builtin:
#this: current component
#form: parent UIForm
#all: entire document
#none: nothing
PrimeFaces has enhanced this with new keywords and composite expression support:
#parent: parent component
#namingcontainer: parent UINamingContainer
#widgetVar(name): component as identified by given widgetVar
You can also mix those keywords in composite expressions such as #form:#parent, #this:#parent:#parent, etc.
PrimeFaces Selectors (PFS) as in #(.someclass) allows you to reference components via jQuery CSS selector syntax. E.g. referencing components having all a common style class in the HTML output. This is particularly helpful in case you need to reference "a lot of" components. This only prerequires that the target components have all a client ID in the HTML output (fixed or autogenerated, doesn't matter). See also How do PrimeFaces Selectors as in update="#(.myClass)" work?
first of all: as far as i know placing dialog inside a tabview is a bad practice... you better take it out...
and now to your question:
sorry, took me some time to get what exactly you wanted to implement,
did at my web app myself just now, and it works
as I sayed before place the p:dialog out side the `p:tabView ,
leave the p:dialog as you initially suggested :
<p:dialog modal="true" widgetVar="dlg">
<h:panelGrid id="display">
<h:outputText value="Name:" />
<h:outputText value="#{instrumentBean.selectedInstrument.name}" />
</h:panelGrid>
</p:dialog>
and the p:commandlink should look like this (all i did is to change the update attribute)
<p:commandLink update="display" oncomplete="dlg.show()">
<f:setPropertyActionListener value="#{lndInstrument}"
target="#{instrumentBean.selectedInstrument}" />
<h:outputText value="#{lndInstrument.name}" />
</p:commandLink>
the same works in my web app, and if it does not work for you , then i guess there is something wrong in your java bean code...
It's because the tab is a naming container aswell... your update should be update="Search:insTable:display" What you can do aswell is just place your dialog outside the form and still inside the tab then it would be: update="Search:display"
Please note that from PrimeFaces 10 and up, you are able to use observer and event.
This allows you to update components based on a custom event name, set by the #obs(event) keyword. For example:
<p:commandButton update="#obs(myEvent)"/>
<h:panelGroup>
<p:autoUpdate on="myEvent"/>
</h:panelGroup>
See:
https://www.primefaces.org/showcase/ui/ajax/observer.xhtml
I know this already has a great answer by BalusC but here is a little trick I use to get the container to tell me the correct clientId.
Remove the update on your component that is not working
Put a temporary component with a bogus update within the component you were trying to update
hit the page, the servlet exception error will tell you the correct client Id you need to reference.
Remove bogus component and put correct clientId in the original update
Here is code example as my words may not describe it best.
<p:tabView id="tabs">
<p:tab id="search" title="Search">
<h:form id="insTable">
<p:dataTable id="table" var="lndInstrument" value="#{instrumentBean.instruments}">
<p:column>
<p:commandLink id="select"
Remove the failing update within this component
oncomplete="dlg.show()">
<f:setPropertyActionListener value="#{lndInstrument}"
target="#{instrumentBean.selectedInstrument}" />
<h:outputText value="#{lndInstrument.name}" />
</p:commandLink>
</p:column>
</p:dataTable>
<p:dialog id="dlg" modal="true" widgetVar="dlg">
<h:panelGrid id="display">
Add a component within the component of the id you are trying to update using an update that will fail
<p:commandButton id="BogusButton" update="BogusUpdate"></p:commandButton>
<h:outputText value="Name:" />
<h:outputText value="#{instrumentBean.selectedInstrument.name}" />
</h:panelGrid>
</p:dialog>
</h:form>
</p:tab>
</p:tabView>
Hit this page and view the error.
The error is:
javax.servlet.ServletException: Cannot find component for expression "BogusUpdate" referenced from
tabs:insTable: BogusButton
So the correct clientId to use would then be the bold plus the id of the target container (display in this case)
tabs:insTable:display
Try change update="insTable:display" to update="display". I believe you cannot prefix the id with the form ID like that.