Every ADF region maintains its own Page Flow scope, this means even if
you have two ADF regions on the same page - each ADF region will have
its own Page Flow scope and it will not be allowed to enter another
region Page Flow scope. If we would be allowed to share Page Flow scope
between different regions, it would be easy to pass data from one ADF
region to another, however this is not allowed by design.
Solutions:
1. ADF Task Flow parameters - preferable option, is simple to use, however sometimes is not enough for complex scenarios
2. Contextual Events - flexible and powerful approach, but can be too complicated. When application grows, is hard to maintain and understand dependency between different Contextual Events. In certain situations, its mandatory to use Contextual Events, for example dependent region refresh
3. Page Definition Access through Data Control - we can access separate ADF region page definition through Data Control directly. While this works, is not advisable because it creates direct dependencies between regions
4. Session Scope-session scope values are accessible by both regions.
Source:http://andrejusb.blogspot.in/2011/02/adf-region-communication-data-exchange.htm
Solutions:
1. ADF Task Flow parameters - preferable option, is simple to use, however sometimes is not enough for complex scenarios
2. Contextual Events - flexible and powerful approach, but can be too complicated. When application grows, is hard to maintain and understand dependency between different Contextual Events. In certain situations, its mandatory to use Contextual Events, for example dependent region refresh
3. Page Definition Access through Data Control - we can access separate ADF region page definition through Data Control directly. While this works, is not advisable because it creates direct dependencies between regions
4. Session Scope-session scope values are accessible by both regions.
Source:http://andrejusb.blogspot.in/2011/02/adf-region-communication-data-exchange.htm
