How to calculate the row values in apex:repeat

Question

I have a VF Page which displays the values from different object as a table. I need to perform the row based calculation in that table. Please find below the example and help me out in solving this.

   Rl R2 Total  Total(%)
A  25 25 50

B  50 75 125

Answer 1

One way i could think of implementing the same is

1)Create a wrapper class for your tables

2)Perform all calculations at the backend and use that to diaplay the data

public class wrappercalc {

public class mainwrap {
    public List < intwrap > Data {
        get;
        set;
    }
}

public class intwrap {
    public integer row1 {
        get;
        set;
    }
    public integer row2 {
        get;
        set;
    }
    public integer sum {
        get;
        set;
    }

    public intwrap(integer i1, integer i2) {
        row1 = i1;
        row2 = i2;
        sum = i1 + i2; //Logic in constructor
    }
}

public List < intwrap > getData() {

    mainwrap m = new mainwrap();

    m.Data = new List < intwrap > ();

    intwrap i1 = new intwrap(25, 30);
    intwrap i2 = new intwrap(50, 100);

    m.Data.add(i1);
    m.Data.add(i2);

    return m.Data;
   }
 }

---

 <apex:page controller="wrappercalc">
   <apex:pageBlock >
     <apex:pageBlockTable value="{!Data}" var="d">
       <apex:column value="{!d.row1}" title="R1"/>
       <apex:column value="{!d.row2}" title="R2"/>
       <apex:column value="{!d.sum}" title="SUM"/>
     </apex:pageBlockTable>
   </apex:pageBlock>
 </apex:page>

The above code should give an idea. The basic wrapper class concept is needed for your example.

Answer 2

Another solution is to generate totals on the fly just using an apex:variable

Here using apex:variable to generate a total and then set value to the footer:

<apex:page controller="MyTest">
<apex:form >

<!-- Need this variables for totals generation -->
<apex:variable value="{!0.00}" var="total1"/>
<apex:variable value="{!0}" var="total2"/>

<apex:pageBlock title="Totals">
<apex:pageBlockTable value="{!accounts}" var="item" id="list1">

    <apex:column value="{!item.name}" width="20%"/>

    <apex:column headerValue="Number1">
        <apex:outputField value="{!item.number1__c}" />

        <!-- Generating a first total -->
        <apex:variable var="total1" value="{!total1 + item.number1__c}" />

        <!-- Footer of the first Cell -->>
        <apex:facet name="footer">
            Total: <span class="t1"></span>
        </apex:facet>
    </apex:column>

    <apex:column headerValue="Number2">
        <apex:outputField value="{!item.number2__c}" />
        <apex:variable var="total2" value="{!total2 + item.number2__c}" />
        <apex:facet name="footer">
            Total: <span class="t2"></span>
        </apex:facet>
    </apex:column>

</apex:pageBlockTable>
</apex:pageBlock>

<script>
    // Here we will set the generated subtotals to the footer cells
    document.getElementsByClassName('t1')[0].innerHTML = '{!total1}';
    document.getElementsByClassName('t2')[0].innerHTML = '{!ROUND(total2,0)}';
</script>

</apex:form>
</apex:page>

Here is the result: