Visualforce list using Apex function and parameter

Question

So at the moment I have a VisualForce Page that uses the following code:

<apex:page standardController="Contact" extensions="RelationshipTreeController">
    <apex:repeat value="{!nameToRelationType}" var="name">
        <apex:repeat value="{!nameToRelationType[name]}" var="relationType">
            <apex:outputText value="{!name} ({!relationType})"/>
            <br></br>
        </apex:repeat>
    </apex:repeat>
</apex:page>

And an extension controller with a Map<String, List<String>> nameToRelationType. The constructor will populate the map and the VF page lists the contents of the map using the nested <apex:repeats

What I would prefer though is to take those keys and just make a List<String> with them. Then the first repeat in the VF page will iterate through that List and within there it will call a function passing in the current String from the List and the function will create the List<String> that would have been the value in the map and return it. Sadly though I cannot call a function with a paramter using <apex:repeat and I cannot use the <apex:param since it cannot be a child of <apex:repeat. So does anyone have any insight? I am pretty new to Salesforce

Answer 1

What you are looking to do is not possible. From what I understand, basically you would prefer to do something like this:

<apex:repeat value="{!keyList}" var="key">
    <apex:repeat value="{!functionToGenerateList(key)}" var="val">
        // do some stuff related to the val
    </apex:repeat>
</apex:repeat>

Unfortunately, this isn't possible since you can not pass parameters back to Visualforce like that.

The way you are currently doing this is what I would consider best practice. It may feel a bit weird, but if you are new to Salesforce development, you will quickly learn to get really familiar with Map. It is utilized heavily. There is some documentation on working with them in Visualforce, but you are already doing it properly.