Passing values between ADF Task Flow

1) IF we have one taskflow inside another taskflow. The PageflowScope can be use to set values into variables i.e.
AdfFacesContext.getCurrentInstance().getPageFlowScope().put("varName","varValue");
and select the child taskflow(this task flow should have relevant parameters defined) and in properties give value to parameter value as #{pageFlowScope.varName}
2) When we have Jsff (region) within which we have taskflow pulled and we need to pass value to this taskflow then go to pagedefinition for the page/region and select this taskflow from executables and in properties you provide value to particular variable like #{pageFlowScope.varName}