RSS feed
More news & opinion »
Performing Comparisons on Custom Labels in VF pages
By Vincent on February 2, 2011
Ran into a strange “bug” today while developing a VF page.
This VF receives parameters through the URL which the VF Controller class parses out and stores in a class variable. The VF page also has an <apex:outputPanel> section which is rendered if the URL parameter equals a specified Custom Label. The code looks like the following:
Example URL:
https://na#.salesforce.com/apex/MyPage?param1=paramValue
Example Custom Label Definition:
Custom Label Name : MyLabel
Custom Label Value : paramValue1
Example Visualforce Page:
<apex:page controller="MyController">
<apex:outputPanel rendered="{!ctrlParam1=='$Label.MyLabel'}">
<apex:outputText value="Hello, World!"/>
</apex:outputPanel>
</apex:page>
Example Controller Class:
public class MyClass{
public String ctrlParam1{get; private set;}
public MyClass(){
map<string> params = ApexPages.currentPage().getParameters();
ctrlParam1= params.get('param1');
}
}
With the configuration details setup as above, the <apex:outputPanel> is not rendered. More specifically, the code rendered="{!ctrlParam1=='$Label.MyLabel'}" evaluates to false.
Playing around a bit with this code, and a lot of head scratching, netted me the following code that does work:
rendered="{!ctrlParam1==$Label.MyLabel}"
(No quotes around the Custom Label). I guess $Label.MyLabel is a variable in and of itself, and not a replacement string as I assumed that it was. Wish Salesforce.com Help and Training had more sample code. Grrr..