[SalesForce] unable to pass parameter to controller

I have a VF page with two select lists. I'm trying to pass the value selected in the first select list to my controller method that returns a list of select options for the second select list. I'm using actionSupport component, but the parameter is not getting passed back to the controller. In my debug, the event fires on the actionSupport and I enter the method, but the parameter value is not getting passed to the controller. I think it might be related to reRender, but I haven't been able to get it to work.

Here is the VF page code:

    <apex:selectList value="{!innovationCategory}" size="1" id="cat">
        <apex:selectOptions value="{!categories}"/>
        <apex:actionSupport event="onchange" reRender="subCat" >
            <apex:param name="myParam" value="{!innovationCategory}" />
        </apex:actionSupport>
    </apex:selectList>
    <apex:selectList value="{!subCategory}" size="1" id="subCat">
        <apex:selectOptions value="{!subCategories}"/>
    </apex:selectList>

Here is the controller method:

public List<SelectOption> getSubCategories(){
    system.debug('**************** we are inside the getSubCategories method');
    string catName = Apexpages.currentPage().getParameters().get('myParam');
    system.debug('**************** catName' + catName);
    Map<String, List<SelectOption>> subCatMap = getMapOfSubCat();
    system.debug('**************** subCatMap ' + subCatMap);
    return subCatMap.get(catName);
}

Thanks for any help.

Best Answer

You don't need a separate param inside actionSupport to pass the value.. the value field in the selectList will hold the selected value.

So in your getSubCategories method, you can directly use the innovationCategory variable.

also you can wrap the select lists inside actionRegion

<apex:actionRegion>
<apex:selectList value="{!innovationCategory}" size="1" id="cat">
    <apex:selectOptions value="{!categories}"/>
    <apex:actionSupport event="onchange" reRender="subCat" >
    </apex:actionSupport>
</apex:selectList>
</apex:actionRegion>

<apex:actionRegion>
<apex:selectList value="{!subCategory}" size="1" id="subCat">
    <apex:selectOptions value="{!subCategories}"/>
</apex:selectList>
</apex:actionRegion>

Related Solutions

[SalesForce] Apex:selectList value not getting set in controller

I have had the same problem. The solution was to use tha native html select list and an visualforce hidden field. After each change on the selectlist the currently selected value is saved to the hidden field:

<!-- Here is the native select list. 
     It is empty, we fill it later with own options.
     Notice, that by onchange the selected value will be send to the hidden field. -->
<select id="someList" onchange="jQuery('[id$=selectedItemHidden]').val(jQuery(this).val());">
</select>

<!-- Hidden field with a reference to the apex variable -->
<apex:inputHidden value="{!selectedAccount}" id="selectedItemHidden"/>

<!-- Here we fill the select list with some options -->
<script>
for(var i = 0; i < optionsArray.length; i++)
{
    var opt = new Option(optionsArray[i],optionsArray[i]);
    jQuery("select#someList").append(opt);
}
<script>

You can pre fill the html select list with options from the database:

Controller:

public class MyClass{
    // Here we define the list with accounts
    public List<Account> accounts { get; set; }

    // In constructor we will read the accounts
    public MyClass(){
        accounts = [ Select Id, Name From Account Limit 10 ];
    }
}

Page:

<!-- Here we just use repeat function to iterate the list -->
<select id="someList">
    <apex:repeat value="{!accounts}" var="a">
        <option value="{!a.id}">{!a.name}</option>
    </apex:repeat>
</select>

[SalesForce] How to pass in a List to a parameter when calling a class method in Test Class

You can either create a List<String> (or List<Id>) variable in your test class and pass it by reference, like any other parameter, or you can use literal initialization syntax.

For the latter, it would look something like this:

public static List<Product2> getSystemProductsMethod(list<string> productIds);

@isTest
public static void testGetSystemProductsMethod() {
    MyClass.getSystemProductsMethod(new List<String>{
        'String1', 
        'String2', 
        ...
    });

    // assertions go here...
}

Note the use of curly braces rather than parentheses, like a constructor would use.

Also worth noting: if your methods are really accepting a List<Id>, declare it as such - not as a List<String>. If the values aren't Ids, naming the variable productIds may create extra confusion for you down the line.

Best Answer

Related Solutions

[SalesForce] Apex:selectList value not getting set in controller

[SalesForce] How to pass in a List to a parameter when calling a class method in Test Class

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