VisualForce - rendering two boolean fields

Question

I'm trying to create a condition on a VF page to show me a field only if the two conditions are met. (I.e. I want to use the 'rendered' attribute twice)

Here is my code:

<apex:inputField value="{!pa.Permanent_User_ID_Collection__c}" 
rendered="{!!DRD_Submited + !recordTypeIsPPDetect == 'Platform_Detect'}"/>

And this is the error I get:

"Incorrect parameter type for operator '+'. Expected Number, Date, DateTime, received Boolean"

Answer 1

As mentioned you should use boolean methods as AND(value1, value2, ...) and NOT(value1)

<apex:inputField 
    value="{!pa.Permanent_User_ID_Collection__c}" 
    rendered="{!AND(NOT(DRD_Submited), recordTypeIsPPDetect == 'Platform_Detect')}"
/>

From design point of view you should not create complex conditions but instead create and use controller property that will isolate field visibility logic of type either Boolean (for single field) or Map<Id, Boolean> (for collection of records)

Answer 2

You can use following:

<apex:inputField value="{!pa.Permanent_User_ID_Collection__c}" 
rendered="{!(!DRD_Submited && (recordTypeIsPPDetect == 'Platform_Detect'))}"/>

Answer 3

For multiple conditions on a rendered attribute, you can also use AND and OR. Example: rendered="{!AND(condition_1,condition_2)}"

For your case, try rendered="{!DRD_Submited && recordTypeIsPPDetect == 'Platform_Detect'}", or rendered="{!AND(DRD_Submited,recordTypeIsPPDetect == 'Platform_Detect')}".