Is it possible to add JSF Components using javascript? In my case , on change of a select option , i need to display a different combination of input controls (like text box(s)). I thought i could use a element and innerHTML property to display the dynamic controls.But it seems to not work!!!
<h:selectOneMenu id="browseType" class="TextBlackNormal"
value="#{adminBean.browseType}" onchange="showDynamicBox(this);"
valueChangeListener="#{adminBean.theValueChanged}">
<f:selectItems value="#{adminBean.browseTypeList}" />
</h:selectOneMenu> </td>
<td>
<div id="dynamicBox" style="display:block"><h:inputText
class="TextBlackNormal" size="32" name="browseValue"
id="browseValue" value="#{adminBean.browseValue}" /></div>
</td>
javascript code :
~~~~~~~~~~~~~~~~
function showDynamicBox(selectObjj)
{
//alert('showDynamicBox ' +showDynamicBox);
if(selectObjj.options[selectObjj.selectedIndex].value=='IBD/Office/IP'
|| selectObjj.options[selectObjj.selectedIndex].value=='APA#' )
{
alert('just about to change');
document.getElementById("dynamicBox").innerHTML='<h:inputText class="TextBlackNormal" size="3" name="val1" id="val1" /> <h:inputText class="TextBlackNormal" size="3" name="val2" id="val2" /> <h:inputText class="TextBlackNormal" size="3" name="val3" id="val3" /> ';
alert(' --> ' +document.getElementById("dynamicBox").innerHTML);
}else{
alert('back to pavillion');
document.getElementById("dynamicBox").innerHTML='<h:inputText class="TextBlackNormal" size="32" name="browseValue" id="browseValue" value="#{adminBean.browseValue}" />';
}
}
Is it possible to add JSF Components using javascript?
No - that would be a security nightmare.
JSF controls run on the server (though might emit JavaScript for a richer client-side experience). Those h:foo elements are interpreted by the server's JSP compiler when it translates the JSP to Java.
JavaScript runs in the browser.
I suggest stating what you want to try and achieve and then ask for suggestions about how to do it using JSF.
You can't add jsf components with javascript. You can simply manipulate the visibility (css display and visibility properties) of existing components.
(and you can use jQuery together with richfaces.)
As McDowell says, you can't add a component to the JSF tree via Javascript, but it sounds like all that you want to do is to swap controls on the page between one big input box or three small ones.
There are several ways to do this:
Have all controls on the page and
show/hide them with javascript. You're doing similar already but bind the 3 small boxes to backend values and toggle display none/block rather than dealing with innerHTML.
Have one set of controls on the page and render them selectively with ajax (eg. richfaces).
Related
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 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 a big fan of angularjs, I started lately to use it in all of my 'coding for fun' projects.
I have a big curiosity:
I have a two inputs, one disabled by a ng-disabled directive and the other disabled with an html tag (A better illustration in this link):
//...
<input type="text" disabled value="This is an html input text disabled" />
<input type="text" ng-disabled="true" value="disabled with angular js directive" />
//...
Using the browser ability I can right click on the input and remove the disabled and ng-disabled tags but only the one with the disabled tag would be editable, the other one will still be tracked by angular even when ng-disabled directives has been removed.
So, When and Why should I prefer using ng directives over native html tags? Which could be the impact of letting angular track all these actions? is it really worth to use it everywhere?
Use the native html 'disabled' if the element should always be disabled. (static, for example if you want to provide an input with text and never let the user change it)
Use angular if it should change based on variables value in the scope.
For example, say a button should change the state of an input.
<input type="button" ng-click="inpDisabled = true" >Disable Input</input>
<input type="text" ng-disabled="inpDisabled" />
live example
No harm will come if you still use ng-disabled="true" but it's redundant.
If you want to make directive static, you shoud use native html
<your-tag disable><your-tag>
against
<your-tag ng-disabled="true"><your-tag>
But AngularJS does not work this way, you shoud initialize your application and controller, then pass a variable as parameter to your directive:
JS:
$scope.isDisabled = true;
HTML:
<your-tag ng-disabled="isDisabled"><your-tag>
You shoud read more tutorials to make things clear
I have a JSP page containing a ADD button to add the rows(a HTML code) via Javascript.
I now need to retain the value in my form by replacing the codes in JSP by struts-tags.
How should I then communicate from struts-tags and JS. Since all the HTML code lies in JS, how should it use struts-tags???
Please help!!
Your question is too vague to give an appropriate answer. However, I recently did something similar to this so I will try and give you a few guidelines.
1.) If you are hoping to populate these rows with information from the server this will require an ajax call. Most likely to an action that returns a snippet of jsp containing only a table row.
I suggest avoiding the struts2-jquery plugin for this unless you already are using it in your application. I would just use jQuery - http://api.jquery.com/jQuery.ajax/
2.) If you wish to gather user input in these rows you will just have to make sure to use appropriate naming for your fields.
Eg: In your java action you have a List< String > names.
You would need to generate the following html via js.
<tbody>
<tr>
<input type="text" name="names[0]">
</tr><tr>
<input type="text" name="names[1]">
</tr><tr>
<input type="text" name="names[2]">
</tr>
</tbody>
3.) If you wish to keep track of the number of added rows you could use this in your jsp...
<s:hidden name="rowsCount" id="rowsCount" value="0">
then within your javascript change the value of that input.
Hope one of those 3 helped!