Property Inheritance
Property inheritance, or sending and receiving, is a widely used concept in Canvas. The application supports an explicit relationship between screens, objects, and controls, where certain property values, such as facilities and SiteService details, are passed from one element to another via an inheritance framework. Screens, objects, and controls can be configured as property senders or property receivers and provide configuration options where you can explicitly define the source of the facility and SiteService. Depending on how you have your screens, objects, and controls configured, the facility and SiteService may be received from any one of the following sources:
- from itself — indicated by selecting <Self> and then explicitly configuring the property
- received from the screen — indicated by selecting Screen, which is always present as a sender
- received from another control — indicated by selecting the Name of the sending control.
Broadcasting
Screens and objects support an additional notification option to broadcast their facility and SiteService selection changes to other open screens. If configured, a <Broadcast> option is available to source the screen's facility and SiteService properties from another open screen.
For example, a Text Tool can be configured to get its facility from the screen and the screen can be configured to get its facility from a Tag Chooser. Or Screen_A might source its facility from Screen_B, which gets its facility from a Tag Chooser.
Receiver or Sender
The following table indicates which controls can receive or send SiteService and/or facility tags from/to the screen or other controls:
| Receive | Send | |||
|---|---|---|---|---|
| SiteService | Facility | SiteService | Facility | |
| Alarm Grid |
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| Button |
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| Chart |
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| CygNet Grid |
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| DDS Button |
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| DDS Edit Box |
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| DDS Text Tool |
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| Detail |
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| Donut |
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| Dynagraph |
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| Facility Emitter |
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| Heat Map |
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| Image |
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| Linear Gauges |
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| Map (layer) |
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| Navigation Button |
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| Nested View |
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| Note Grid |
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| Object |
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| Object Container |
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| Relative Facility Tree |
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| Screen |
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| Search Box |
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| SetPoint Button |
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| Shape |
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| Sparkline |
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| Tag Chooser |
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| Text Tool |
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| Tile View |
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| Tree Map |
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| UIS Command Button |
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| Value Indicator |
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