Value provider subscriptions for sparsely populated data objects

A system comprising:

• at least one processor;
• a calling routine being configured to operate on said at least one processor, said calling routine being configured to identify a data object having a first property and being configured to issue a first property change request for said first property, said first property change request being an event;
• a subscription service for said first property change request having a first value provider subscribed to said subscription service, said subscription service being configured to receive said first property change request and being configured to cause said first value provider to execute based on said first property change request;
• said subscription service being further configured to receive a first value from a first value provider and being configured to issue a property changed event in response to said first property change request, said calling routine having a subscription to said property changed event, said calling routine being further configured to receive said first value as a result of said property changed event;
• and
• said subscription service being further configured to install a second value provider, said second value provider being configured to provide a second value for said first property, said second value provider being configured to execute based on a property change request for said first property, said second value provider being created after said calling routine is created.

Computer-readable storage hardware having computer-executable instructions embodied thereon that, when executed by at least one processor, cause the at least one processor to perform acts comprising:

• identifying a data object comprising a plurality of properties;
• for a first property within said plurality of properties, a calling routine issuing a first property request event comprising said first property;
• identifying a first value provider having a subscription for said first property request event and causing said first value provider to determine a first property value for said first property;
• receiving said first property value for said first property from said first value provider in response to said first property request event and issuing a first property changed event;
• receiving said first property changed event and processing said first property value in response to receiving said first property changed event;
• receiving a second value provider;
• and
• installing said second value provider, said second value provider providing a second value for said first property and issuing a second property changed event, said second value provider executing to provide said second value based on a property request event for said first property, said second value provider being created after said calling routine is created.