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Completing the Steps tab — Entering preconditions

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Use a precondition to conditionally skip execution of a step. The system evaluates whether specified conditions are met before it executes the method or instruction referenced in the step. If false, the rest of the step is skipped.

The precondition icon on the Steps tab identifies the precondition column. When a step is not selected, a checkmarkzzzindicates that this step has a precondition defined and enabled. When the row is activated, clickzzz to add a precondition or the zzz to access the details of the precondition. Alternatively, clickzzzat the left of the step row to view all step fields, including the precondition fields.

Preconditions

Use the standard add row (Append Row), append row (image/img00020.gif), and delete row (zzz) buttons with this array. Order is significant.

Field

Description
Enabled?

Select to turn on the precondition test. If this box is not selected:

  • At runtime, the system ignores all the precondition rows
  • A warning message appears when you save the Activity form
When

Identify a when condition rule that specifies this precondition. Or enter an expression starting with "=" that returns true or false, such as

=(.pyDoorisLocked == false).

Click the pencil icon (Pencil) to review or update the when condition rule. Click the magnifying glass icon (zzz) to start the Expression Builder.
If True

Select to indicate what is to happen if the when condition evaluates to True. Complete both an If True and an If False option for each precondition row.

if True
  • Continue Whens — Advance to the next row of the precondition array, before executing the step.
  • Skip Whens — Skip all the later rows and execute the step.
  • Jump To — Jump to a specific higher-numbered activity step that contains a label. Entering the step's Label name in the True Param field. Processing resumes at the labeled step. zzzYou cannot jump to a label for a lower-numbered step.
  • Skip step — Skip the current step. For a repeating step, this ends the iteration.
  • Exit This Iteration — End the current iteration, and advance to the next iteration.
  • End Activity — End execution of this activity. The rest of the step is not executed.
True Param

If you selected Jump To, enter the Label name of the step to jump to.

If you entered Exit Activity, enter an integer: 0 for a status of Good, any negative integer for a status of Fail, and any positive integer for a status of Warn.

If False

Choose what is to happen if the condition evaluates to false. The choices are the same as those for If True. As a good practice, complete both an If True and If False option for each row.
False Param

If you selected JumpTo, enter the label of the step to jump to.

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