Setting Flow Variable Values from a visualforce Page

Question

I am trying to pass value from a visualforce page to a flow using

.

Document:https://developer.salesforce.com/docs/atlas.en-us.pages.meta/pages/pages_flows_setting_values.htm

However when referencing field values from the Account in my flow I get an error saying: The flow failed to access the value for Account.customfield__c because it hasn't been set or assigned.

My question is what all fields are passed from the visualforce page to the flow.

Do I need to define the individual fields in my flow under 'Assign the records's fields to variables to reference them in your flow' before using them.

Answer 1

If you go through the documentation it says that, following variables can be passed through <apex:param> component:

• sObject variables,
• collection variables
• sObject collection variables

You can set only variables that allow input access. For each flow variable, input access is controlled by:

• The Input/Output Type variable field in the Cloud Flow Designer
• The isInput field on FlowVariable in the Metadata API

So, define the input/output type variables in the flow and at the time of passing parameters from visualforce it should match with those input/output type variables.