Pass object data to Apex using checkboxes on visualforce table

Question

I am using Visualforce to list out a few different opportunities a checkbox for each one. My goal is to select an opportunity by clicking the checkbox, then pressing a commandbutton to pass that opportunity info into apex. I am setting the value field of the checkbox to an opportunity object in my apex controller but it is trying to return a boolean instead of the opportunity object. Here is a snippet of my VF and Apex:

VF:

<apex:page standardController="System__c" extensions="SystemAddToOp" recordSetVar="system__c" >    
<apex:form >
    <apex:pageMessages ></apex:pageMessages>
    <apex:pageBlock title="Add These Systems to an Opportunity">
        <apex:pageBlockButtons >
            <apex:commandButton action="{!updateSystems}" value="Add Selected Systems to Opportunity" />
        </apex:pageBlockButtons>
        <apex:pageBlockTable value="{!ops}" var="o">
            <apex:column value="{!o.Name}"/>
            <apex:column value="{!o.id}"/>
            <apex:column value="{!o.CloseDate}"/>
            <apex:column value="{!o.Amount}"/>
            <apex:column headerValue="Select">
                <apex:inputCheckbox value="{!selectedOp}"/>
            </apex:column>
        </apex:pageBlockTable> 
    </apex:pageBlock>
</apex:form>

APEX (snippet):

public Opportunity selectedOp{get;set;}
public PageReference updateSystems()
{       
    insert selectedOp;
    system.debug(selectedOp);

    return null;
}

Any guidance here would be much appreciated. Thanks!

Answer 1

The first thing you should know is that you can't have more than 1 input set to the same value. Otherwise itll always be the value of the last input.

<apex:inputCheckbox value="{!selectedOp}"/>

With that, the only check box that will work is the last check box on the page. If this was a field on the opp you would be fine but there's a better way (see below).

Second thing you should know is check boxes are boolean so you'll only ever get true/false, you'll never get any opp specific information this way.

What you need to do is create a wrapper class:

public class oppWrapper {
    public Opportunity obj { get; set; }
    public Boolean selected { get; set; }

    public oppWrapper(Opportunity opp) {
        this.obj = opp;
        this.selected = false;
    }
}

Then create a list of this object:

List<OppWrapper> wrappedOpps = new List<OppWrapper>();

for (Opportunity opp : opportunities) {
    wrappedOpps.add(new oppWrapper(opp));
}

Display this onto your page:

<apex:pageBlockTable value="{!wrappedOpps}" var="opp">
    <apex:column value="{!opp.selected}"/>
    <apex:column value="{!opp.obj.Name}"/>
</apex:pageBlockTable>

Lastly, your command button will loop through this list to find the selected opp(s)

public void action() {
    List<Opportunity> selectedOps = new List<Opportunity>();
    for (oppWrapper ow : wrappedOpps) {
        if (ow.selected) {
            selectedOps.add(ow.obj);
        }
    }

    // Do what ever you want with your selected opps
}

I made a component a while back (pretty old so don't judge me on the code quality) that does a good job at creating a list of records and wrapping them with a checkbox. It also uses the standard set controller and provides some pagination, sorting and filtering options IIRC.