Using the Canvas Editor

The trigger Canvas Editor provides a graphical flow chart style tool to define, view and edit triggers.
Both the Canvas Editor and the List Editor provide the same ability to define triggers, they just use a different trigger definition approach: flow chart style (Canvas Editor) or list style (List Editor).

The following example shows a trigger's action diagram.


The simple example trigger is defined with a Set action, an If action, and a second Set action.
The diagram also shows the Start block and End Execution (Success) and End Execution (Failure) actions.

  1. The Start action block indicates the beginning of the trigger's execution and is routed to the first action in the trigger.
    When the Set action is successful, the output is routed to the next action (the If action).
    The Set action has a red output point used for failure handling.
  2. When the If expression evaluates to true, the output is routed to the next action (the second Set action).
    When the If expression evaluates to false, the output is routed to End Execution (Success).
    The If action has a red output point used for failure handling. The End Execution (Failure) path is taken when the If expression fails (an example would be trying to access a device variable that could not be accessed)
  3. When the second Set action is successful, the output is routed to End Execution (Success).
    The second Set action also has a red output point used for failure handling.
  4. The End Execution (Failure) action is used by the canvas Editor to indicate the trigger has ended its execution with a Failure completion. This is equivalent to the ENDERR route when using the List Editor. The trigger statistics on its project tab will have an increase in the Failures counter.
  5. The End Execution (Success) action is used by the canvas Editor to indicate the trigger has ended its execution with a Success completion. This is equivalent to the ENDOK route when using the List Editor. The trigger statistics on its project tab will have an increase in the Successes counter.

The reference sections: Trigger event type reference and Trigger actions reference provide the reference information along with concepts and examples of the available trigger event types and trigger actions.

Highlights

This guide describes the general use of the Canvas Editor and contains the following: