| 主权项 |
1. A computer-implemented method, comprising:
selecting, by data processing apparatus, expandable content items, and for each expandable content item;
selecting, by the data processing apparatus, metadata describing features of the expandable content item, the metadata describing features including:dimension features specifying at least one of unexpanded display dimensions for the expandable content item in an unexpanded state and expanded display dimensions for the expandable content item in an expanded state;one or more specified expansion events for the expandable content item, each specified expansion event being one of a set of enumerated expansion events, each enumerated expansion event being an event for which the occurrence causes an expandable content item to expand from an unexpanded state to an expanded state, each specified expansion event being an event for which the expanding content item is specified to expand from the unexpanded state to the expanded state;rendering a resource that includes the expandable content item in a virtual machine instance;generating an occurrence of each of the enumerated expansion events in the virtual machine instance, and after the occurrence of each enumerated expansion event, determining whether the expandable content item expanded from the unexpanded state to the expanded state; andvalidating the expandable content item only when the expandable content item expands from the unexpanded state to the expanded state for each specified expansion event, and does not expand from the unexpanded state to the expanded state for each enumerated expansion event that is not included in the one or more specified expansion events. |
