Initialization, state and notifications#
The following methods and properties of DisplayPluginViewModel provide display initialization, state and notifications
- Display initialization
OnInitialised()
- Called when display is first initialized (programmatic parameters should ideally be added within this override)
- Display state properties
ActiveCompositeSessionContainer
- Access to compare set associated with display (can be
null
if no association)
- Access to compare set associated with display (can be
ServiceContext
- Access to per display services
IsSelected
- True when page is active and display is shown, false when display is overlaid by another display
CanRetrieveData
- False when display is inactive or no session is associated and therefore display should not retrieve data
ScopeIdentity
- Unique identity of display (mainly used to associate results of a data request to a display)
- Display change notifications
OnActiveDisplayPageChanged(bool isActive)
- Called whenever page is switched (
isActive
is true when the active page contains the display)
- Called whenever page is switched (
OnCanRenderDisplayChanged(bool canRender)
- Called whenever display visibility changes (
canRender
is true when display is visible)
- Called whenever display visibility changes (
Important
CanRetrieveData
should be used exclusively for deciding whether it is necessary to make data requests.
Attention
Do NOT access ActiveCompositeSessionContainer
when CanRetrieveData
is false, as an unexpected exception may be raised