Problem: Sometimes you will want to access a component from javascript with
getElementById, but id's are generated dynamically in JSF, so you
need a method of getting an objects id. I answer below on how you can do this.
Original Question:
I want to use some code like below. How can I reference the inputText JSF component in my Javascript?
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core">
<head>
<title>Input Name Page</title>
<script type="javascript" >
function myFunc() {
// how can I get the contents of the inputText component below
alert("Your email address is: " + document.getElementById("emailAddress").value);
}
</script>
</head>
<h:body>
<f:view>
<h:form>
Please enter your email address:<br/>
<h:inputText id="emailAddresses" value="#{emailAddresses.emailAddressesStr}"/>
<h:commandButton onclick="myFunc()" action="results" value="Next"/>
</h:form>
</f:view>
</h:body>
</html>
Update: this post Client Identifiers in JSF2.0 discusses using a technique like:
<script type="javascript" >
function myFunc() {
alert("Your email address is: " + document.getElementById("#{myInptTxtId.clientId}").value);
}
</script>
<h:inputText id="myInptTxtId" value="backingBean.emailAddress"/>
<h:commandButton onclick="myFunc()" action="results" value="Next"/>
Suggesting that the attribute id on the inputText component
creates an object that can be accessed with EL using #{myInptTxtId},
in the above example. The article goes on to state that JSF 2.0 adds
the zero-argument getClientId() method to the UIComponent class.
Thereby allowing the #{myInptTxtId.clientId} construct suggested
above to get the actual generated id of the component.
Though in my tests this doesn't work. Can anyone else confirm/deny.
The answers suggested below suffer from drawback that the above
technique doesn't. So it would be good to know if the above technique
actually works.
You need to use exactly the ID as JSF has assigned in the generated HTML output. Rightclick the page in your webbrowser and choose View Source. That's exactly the HTML code which JS sees (you know, JS runs in webbrowser and intercepts on HTML DOM tree).
Given a
<h:form>
<h:inputText id="emailAddresses" ... />
It'll look something like this:
<form id="j_id0">
<input type="text" id="j_id0:emailAddress" ... />
Where j_id0 is the generated ID of the generated HTML <form> element.
You'd rather give all JSF NamingContainer components a fixed id so that JSF don't autogenerate them. The <h:form> is one of them.
<h:form id="formId">
<h:inputText id="emailAddresses" value="#{emailAddresses.emailAddressesStr}"/>
This way the form won't get an autogenerated ID like j_id0 and the input field will get a fixed ID of formId:emailAddress. You can then just reference it as such in JS.
var input = document.getElementById('formId:emailAddress');
From that point on you can continue using JS code as usual. E.g. getting value via input.value.
See also:
How to select JSF components using jQuery?
Update as per your update: you misunderstood the blog article. The special #{component} reference refers to the current component where the EL expression is been evaluated and this works only inside any of the attributes of the component itself. Whatever you want can also be achieved as follows:
var input = document.getElementById('#{emailAddress.clientId}');
with (note the binding to the view, you should absolutely not bind it to a bean)
<h:inputText binding="#{emailAddress}" />
but that's plain ugly. Better use the following approach wherein you pass the generated HTML DOM element as JavaScript this reference to the function
<h:inputText onclick="show(this)" />
with
function show(input) {
alert(input.value);
}
If you're using jQuery, you can even go a step further by abstracting them using a style class as marker interface
<h:inputText styleClass="someMarkerClass" />
with
$(document).on("click", ".someMarkerClass", function() {
var $input = $(this);
alert($input.val());
});
Answer: So this is the technique I'm happiest with. Doesn't require doing too much weird stuff to figure out the id of a component. Remember the whole point of this is so you can know the id of a component from anywhere on your page, not just from the actual component itself. This is key. I press a button, launch javascript function, and it should be able to access any other component, not just the one that launched it.
This solution doesn't require any 'right-click' and see what the id is. That type of solution is brittle, as the id is dynamically generated and if I change the page I'll have to go through that nonsense each time.
Bind the component to a backing bean.
Reference the bound component wherever you want.
So here is a sample of how that can be done.
Assumptions: I have an *.xhtml page (could be *.jsp) and I have defined a backing bean. I'm also using JSF 2.0.
*.xhtml page
<script>
function myFunc() {
var inputText = document.getElementById("#{backBean.emailAddyInputText.clientId}")
alert("The email address is: " + inputText.value );
}
</script>
<h:inputText binding="#{backBean.emailAddyInputText}"/>
<h:commandButton onclick="myFunc()" action="results" value="Next"/>
BackBean.java
UIInput emailAddyInputText;
Make sure to create your getter/setter for this property too.
Id is dynamically generated, so you should define names for all parent elements to avoid j_id123-like ids.
Note that if you use jQuery to select element - than you should use double slash before colon:
jQuery("my-form-id\\:my-text-input-block\\:my-input-id")
instead of:
jQuery("my-form-id:my-text-input-block:my-input-id")
In case of Richfaces you can use el expression on jsf page:
#{rich:element('native-jsf-input-id')}
to select javascript element, for example:
#{rich:element('native-jsf-input-id')}.value = "Enter something here";
You can view the HTML source when this is generated and see what the id is set to, so you can use that in your JavaScript. As it's in a form it is probably prepending the form id to it.
I know this is not the JSF way but if you want to avoid the ID pain you can set a special CSS class for the selector. Just make sure to use a good name so that when someone reads the class name it is clear that it was used for this purpose.
<h:inputText id="emailAddresses" class="emailAddressesForSelector"...
In your JavaScript:
jQuery('.emailAddressesForSelector');
Of course you would still have to manually manage class name uniqueness.
I do think this is maintainable as long as you do not use this in reusable components. In that case you could generate the class names using a convention.
<h:form id="myform">
<h:inputText id="name" value="#{beanClass.name}"
a:placeholder="Enter Client Title"> </h:inputText>
</h:form>
This is a small example of jsf. Now I will write javascript code to get the value of the above jsf component:
var x = document.getElementById('myform:name').value; //here x will be of string type
var y= parseInt(x,10); //here we converted x into Integer type and can do the
//arithmetic operations as well
Related
I have an input in a form built with aura (Salesforce JS framework):
<input class=" input uiInput uiInputText uiInput--default uiInput--input" type="text" aria-describedby="5284:0" placeholder="" id="7:4790;a" data-aura-rendered-by="17:4790;a" data-aura-class="uiInput uiInputText uiInput--default uiInput--input" data-interactive-lib-uid="54" aria-required="true">
I need to change the value of this input using javascript.
However, when doing:
document.getElementById("7:4790;a").value = "random value";
Visually, it changes the value in the input, but it is not taken into account when saving as if I didn't change anything.
How can I achieve this ?
Do I need to trigger a specific event so that aura takes notice of the new data ?
You need to create an attribute of string type.
<aura:attribute name="myInputValue" type="String" />
Pass the attribute to the value property of the input tag.
<input .... value="{! v.myInputValue}" />
Now, whenever you want to change the value in the input, you can simply do this from your javascript function:
component.set('v.myInputValue, "My new String" />
Important Note: Salesforce frameworks don't allow DOM level manipulation due to a security architecture called Locker service. It is not advisable to follow DOM level Manipulation. Instead, follow the state-based approach like above.
Problem: Sometimes you will want to access a component from javascript with
getElementById, but id's are generated dynamically in JSF, so you
need a method of getting an objects id. I answer below on how you can do this.
Original Question:
I want to use some code like below. How can I reference the inputText JSF component in my Javascript?
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core">
<head>
<title>Input Name Page</title>
<script type="javascript" >
function myFunc() {
// how can I get the contents of the inputText component below
alert("Your email address is: " + document.getElementById("emailAddress").value);
}
</script>
</head>
<h:body>
<f:view>
<h:form>
Please enter your email address:<br/>
<h:inputText id="emailAddresses" value="#{emailAddresses.emailAddressesStr}"/>
<h:commandButton onclick="myFunc()" action="results" value="Next"/>
</h:form>
</f:view>
</h:body>
</html>
Update: this post Client Identifiers in JSF2.0 discusses using a technique like:
<script type="javascript" >
function myFunc() {
alert("Your email address is: " + document.getElementById("#{myInptTxtId.clientId}").value);
}
</script>
<h:inputText id="myInptTxtId" value="backingBean.emailAddress"/>
<h:commandButton onclick="myFunc()" action="results" value="Next"/>
Suggesting that the attribute id on the inputText component
creates an object that can be accessed with EL using #{myInptTxtId},
in the above example. The article goes on to state that JSF 2.0 adds
the zero-argument getClientId() method to the UIComponent class.
Thereby allowing the #{myInptTxtId.clientId} construct suggested
above to get the actual generated id of the component.
Though in my tests this doesn't work. Can anyone else confirm/deny.
The answers suggested below suffer from drawback that the above
technique doesn't. So it would be good to know if the above technique
actually works.
You need to use exactly the ID as JSF has assigned in the generated HTML output. Rightclick the page in your webbrowser and choose View Source. That's exactly the HTML code which JS sees (you know, JS runs in webbrowser and intercepts on HTML DOM tree).
Given a
<h:form>
<h:inputText id="emailAddresses" ... />
It'll look something like this:
<form id="j_id0">
<input type="text" id="j_id0:emailAddress" ... />
Where j_id0 is the generated ID of the generated HTML <form> element.
You'd rather give all JSF NamingContainer components a fixed id so that JSF don't autogenerate them. The <h:form> is one of them.
<h:form id="formId">
<h:inputText id="emailAddresses" value="#{emailAddresses.emailAddressesStr}"/>
This way the form won't get an autogenerated ID like j_id0 and the input field will get a fixed ID of formId:emailAddress. You can then just reference it as such in JS.
var input = document.getElementById('formId:emailAddress');
From that point on you can continue using JS code as usual. E.g. getting value via input.value.
See also:
How to select JSF components using jQuery?
Update as per your update: you misunderstood the blog article. The special #{component} reference refers to the current component where the EL expression is been evaluated and this works only inside any of the attributes of the component itself. Whatever you want can also be achieved as follows:
var input = document.getElementById('#{emailAddress.clientId}');
with (note the binding to the view, you should absolutely not bind it to a bean)
<h:inputText binding="#{emailAddress}" />
but that's plain ugly. Better use the following approach wherein you pass the generated HTML DOM element as JavaScript this reference to the function
<h:inputText onclick="show(this)" />
with
function show(input) {
alert(input.value);
}
If you're using jQuery, you can even go a step further by abstracting them using a style class as marker interface
<h:inputText styleClass="someMarkerClass" />
with
$(document).on("click", ".someMarkerClass", function() {
var $input = $(this);
alert($input.val());
});
Answer: So this is the technique I'm happiest with. Doesn't require doing too much weird stuff to figure out the id of a component. Remember the whole point of this is so you can know the id of a component from anywhere on your page, not just from the actual component itself. This is key. I press a button, launch javascript function, and it should be able to access any other component, not just the one that launched it.
This solution doesn't require any 'right-click' and see what the id is. That type of solution is brittle, as the id is dynamically generated and if I change the page I'll have to go through that nonsense each time.
Bind the component to a backing bean.
Reference the bound component wherever you want.
So here is a sample of how that can be done.
Assumptions: I have an *.xhtml page (could be *.jsp) and I have defined a backing bean. I'm also using JSF 2.0.
*.xhtml page
<script>
function myFunc() {
var inputText = document.getElementById("#{backBean.emailAddyInputText.clientId}")
alert("The email address is: " + inputText.value );
}
</script>
<h:inputText binding="#{backBean.emailAddyInputText}"/>
<h:commandButton onclick="myFunc()" action="results" value="Next"/>
BackBean.java
UIInput emailAddyInputText;
Make sure to create your getter/setter for this property too.
Id is dynamically generated, so you should define names for all parent elements to avoid j_id123-like ids.
Note that if you use jQuery to select element - than you should use double slash before colon:
jQuery("my-form-id\\:my-text-input-block\\:my-input-id")
instead of:
jQuery("my-form-id:my-text-input-block:my-input-id")
In case of Richfaces you can use el expression on jsf page:
#{rich:element('native-jsf-input-id')}
to select javascript element, for example:
#{rich:element('native-jsf-input-id')}.value = "Enter something here";
You can view the HTML source when this is generated and see what the id is set to, so you can use that in your JavaScript. As it's in a form it is probably prepending the form id to it.
I know this is not the JSF way but if you want to avoid the ID pain you can set a special CSS class for the selector. Just make sure to use a good name so that when someone reads the class name it is clear that it was used for this purpose.
<h:inputText id="emailAddresses" class="emailAddressesForSelector"...
In your JavaScript:
jQuery('.emailAddressesForSelector');
Of course you would still have to manually manage class name uniqueness.
I do think this is maintainable as long as you do not use this in reusable components. In that case you could generate the class names using a convention.
<h:form id="myform">
<h:inputText id="name" value="#{beanClass.name}"
a:placeholder="Enter Client Title"> </h:inputText>
</h:form>
This is a small example of jsf. Now I will write javascript code to get the value of the above jsf component:
var x = document.getElementById('myform:name').value; //here x will be of string type
var y= parseInt(x,10); //here we converted x into Integer type and can do the
//arithmetic operations as well
I'm running into a bit of an issue. My JavaScript function returns "undefined" when using master pages. However, when I'm not using master pages, it works fine. Here is my code:
HTML:
<input id="txtPhoneNumberAreaCode" class="TextBox" runat="server" type="text" onkeyup="GoToNextTextBox(this.id, 3, 'cphMainArea_txtPhoneNumberFirstThree')" />
The Javascript:
function GoToNextTextBox(CurrentTextBox, MaxCharLength, NextTextBox) {
alert(CurrentTextBox.value);//pops up "undefined"
if (CurrentTextBox.value.length == MaxCharLength) {
NextTextBox.focus();
NextTextBox.style.backgroundColor = '#FFFFFF';
}
Again, this works fine when not using master pages. So I'm completely confused.
This is because, you are doing it wrong.
In GoToNextTextBox(), you are expecting a DOM element, but you are passing only its id.
DO this:
<input id="txtPhoneNumberAreaCode" class="TextBox" runat="server" type="text"
onkeyup="GoToNextTextBox(this, 3, 'cphMainArea_txtPhoneNumberFirstThree')" />
When using master pages and user controls the rendered ID of your controls change, but there is a way to stop it.
Let's say you have a Textbox
<asp:Textbox id="txtName" runat="server"></asp:Textbox>
on a standard asp page, it's id will be as you expect, txtName
Now you add a master page, called Site.Master. In your rendered html, the controls name is now different.
cntl1_Site_txtName
I might have the syntax of the new name a bit off, but you can view source and find it for yourself.
There is a way to control that though. There is a property on your page, ClientIDMode.
If i remember correctly it has 3 or 4 options. Auto ID is default I believe.
If you set it to static for that page, then you will no longer get the verbose control IDs, they will be as you expect.
This can be a downfall when using things like Repeaters though. You will not have easy access to specific fields if they do not have the verbose ID
I have the following code.
<h:form id="Form">
<div class="pageBody">
<h:outputLabel id="lbl" styleClass="formLabel" value="#{messages['lable.email']}:" />
<s:button id="login" label="#{messages['login.button']}" actionBean="#{account}" actionMethod="login" />
</div>
</h:form>
Here is the javascript
var obj = document.getElementById("Form:lbl"); //This works
var obj1 = document.getElementById("Form:login"); //This doesnt work
Keep in mind that <s:button> is a custom JSF Component.
Any help is appreciated
It should work fine with custom components. Is it a custom component or a composite component? The problem you're having and the presence of JSF 2.0 tag indicates that it's actually a componsite component. For the difference between custom tags, custom components and composite components, check When to use <ui:include>, tag files, composite components and/or custom components?
In this answer, I'll assume that it's indeed a composite component.
First of all, JavaScript works with HTML DOM tree, not with JSF component tree. JavaScript namely runs on webbrowser, not on webserver. JSF runs on webserver, produces a bunch of HTML and sends it to webbrowser. The document.getElementById() accepts only HTML DOM element ID's.
So, to find out which HTML DOM element ID the <s:button> has generated, you should open the JSF page in your webbrowser, do a rightclick and then View Source and locate the generated HTML element in the HTML source.
In case of your <s:button id="login"> composite component which in turn uses for example <h:commandButton id="button"> in the implementation, then it'll look like something like this:
<input type="submit" id="Form:login:button" />
A composite component by itself namely an NamingContainer component, which prepends the IDs like that. The <h:form> is also such a component. This enables you to use multiple composite components inside the same parent container.
You should use exactly that ID in your JavaScript function.
var button = document.getElementById("Form:login:button");
I have apex tag that generate input text field.
<apex:page id="my_page">
<apex:inputText id="foo" id="c_txt"></apex:inputText>
</apex:page>
When someone clicks this field, I want to execute javascript.
But when I check the HTML source, this apex tag which becomes input tag has (I think) dynamically generated part.
<input type="text" size="50" value="Tue Nov 16 00:00:00 GMT 2010"
name="j_id0:j_id3:j_id4:c_txt" id="j_id0:j_id3:j_id4:c_txt">
As you can see id has junk part :(
id="j_id0:j_id3:j_id4:c_txt"
In my Javascript I'm trying to getElementById('c_txt') but this does not work of course. How to deal with this???
UPDATE
Seems like I can do this but not working...
<apex:includeScript value="{!URLFOR($Resource.datepickerjs)}"></apex:includeScript>
<apex:inputText id="foo" id="c_txt" onclick="javascript:displayDatePicker()" />
datepickerjs
var elem = getElementById('c_txt');
alert(elem);
The alert shows 'null' so something must be wrong.
Even this alert returns null...
var targetDateField = document.getElementById('{!$Component.my_page:c_txt}');
alert(targetDateField);
You can use the $Component notation in javascript, you use it like so:
var e = document.getElementById("{!$Component.ComponentId}");
One thing to be wary of though, is if your element is contained within several levels of Visualforce tags which have IDs:
<apex:pageBlock id="theBlock">
<apex:pageBlockSection id="theBlockSection">
<apex:commandLink action="{!someAction}" value="LINK!" id="theLink"/>
// snip
// in javascript you would reference this component using:
document.getElementById("{!$Component.theBlock.theSection.theLink}");
I got solution to my problem.
$Compoent global visualforce expression can only be used in visualforce code not inside of
Javascript as far as my search.
Below code works fine. It outputs the value in the inputText field to js alert message Now you can pass id attribute to the Javascript and process whatever the task needed.
Created Date: <apex:inputText id="dah" value="{!created}" size="50"
onclick="javascript:go('{!$Component.dah}')"></apex:inputText>
<script>
function go(field) {
var huh = document.getElementById(field).value;
alert(huh); //returns the string u put inside of input text field
}
</script>