Activity form
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The icon on the Steps tab identifies the iteration column. Use iterations to repeat a step or a contiguous sequence of steps a number of times, or until a condition is met. You can iterate over the elements in an aggregate property — a Value List
, Value Group
, Page List
, or Page Group
.
This feature provides a limited form of enumeration or looping, similar to the "repeat until" or "do while" or "repeat from X to Y" structures of programming languages.
In a child step within a multistep iteration, right-click to access a context menu. You can copy, cut, or paste child steps within the same iteration.
Repeating a single step using the iteration box
When a step row is not selected, a indicates that this step is iterated. When a step row is selected, clickto add an iteration or theto access the details of the iteration. Use this selection box to indicate whether and how to repeat the step. You can cause the step to repeat a specific number of times, or until a specific result is reached.
Use the Iteration Box to apply the step to more than one page or object. Select:
For Each Page
For Each Embedded Page
For Each Element in Value List
For Each Element in Value Group
For Loop
To exit the iteration before processing all elements in the iteration, complete a transition that is true after the last desired element is processed.
When processing the For Loop
or iterating over a Value List
or Page List
property, the parameter param.pyForEachCount
holds the current iteration number. You can examine (but not alter) this value in the step. For example, to iterate only over the first ten pages or values, you can exit the iteration when pyForEachCount
is greater than 10.
If the body of the iteration requires more than one step to code, create an activity and call the activity in the iterated step. Select the Pass current parameter page? box to share the parameter page of the current activity with the called activity.
Select the For Each Page
option to sequence through all pages of a specified class or classes and perform a method or instruction for each page. Leave the Step Page field blank. Each time the step repeats, the step's page changes.
For the optional Valid Classes parameter, enter a class or classes. (Click the Add Row icon beneath the Valid Classes box to add more than one class.)
When Valid Classes is not blank, iteration processing skips over any page with a class that does not appear on the list, or is not derived from one of these classes.
Use For Each Embedded Page
option to apply a method or instruction to each embedded page in a Page List
or Page Group
property. Use the iteration choice to specify processing that is to occur for each embedded page. For example, you can:
and so on.
Identify the property containing the embedded pages in the Step Page field. The SmartPrompt list for the Step Page field shows only Page List
and Page Group
properties.
For the optional Valid Classes parameter, enter a class or classes. (Click the Add Row icon beneath the Valid Classes box to add more than one class.)
Page List
or Page Group
are included in the iteration.For Each Element in a Value List
Select the For Each Element in a Value List
option to repeat the step for each element in a Value List
property.
Each time the step repeats, the system applies a method or instruction of your choice (such as Property-Set) to the current property. Use the <CURRENT>
index value to refer to the current property element.
When you select this iteration form, a Property Name field appears. Identify the Value List
property in the Property Name field.
For Each Element in a Value Group
Select the For Each Element in a Value Group
option to repeat the step for each element in a Value Group
property.
When you select this iteration form, a Property Name field appears. Identify the Value Group
property in the Property Name field.
Each time the step repeats, the system applies a method or instruction of your choice to the current property. Use the <CURRENT>
index value to refer to the current property.
Select the For Loop
option to repeat the step a number of times determined by the values of integer constants or integer properties.
Enter integer constant values or integer property references for the Start, Stop, and Increment fields. The Increment must be a positive integer.
The system accesses these three values once before starting the iteration. The iteration may occur zero, one, or many times, repeating until the incremented value is greater than or equal to the stop value (unless a transition causes processing to end earlier).
The symbolic reference <CURRENT>
may be used only in the activity step that defines the iteration. If that step calls another activity, the symbolic reference <CURRENT>
cannot be used in the called activity; rather, aspects of the current iteration are available on the parameter page of the called activity:
For Each Element in a Value List
or For Each Element in a Value Group
, the symbol <CURRENT>
refers to the value of ClipboardProperty corresponding to the iteration. For the called activity, this corresponds to the pyPropertyValue
parameter described below.<CURRENT>
refers to the index number of the current iteration, and corresponds to the pyForEachCount
parameter.The scope of an iteration can be more than one step. The iteration type and conditions are set in the first step of a multistep iteration.
To create a multistep iteration:
Page List
or Page Group
property on the step page of the parent. (In this case, complete the For Each Embedded Page
iteration details for the child step.)Numbered child steps are executed in sequence NNN.0, NNN.1, NNN.2 ... then NNN.0 again, until the iteration ends or a transition causes a jump to a labeled step.
To convert an iteration sequence to comments, enter two slash characters // in the Label field of the parent step. The parent and all child steps become comments.
You can't jump from outside a multistep iteration to any step within the iteration (except to the starting — parent — step). You can jump from any step in an iteration (parent or child) to a higher-numbered step (that is not within any iteration).
For an example of multistep and nested iterations, see the PDN article 25610 How to use multistep loops and nested loops in activities.
By using the Add Child Step icon ( ) on a child step numbered NNN.Z, you can create a nested iteration.
For example, clicking a child step numbered 14.8 converts this to 14.8.0, and inserts a second-level child step numbered 14.8.1. Complete the iteration conditions for step 14.8.0.
Use care in entering the Step Page for the parent step of a nested iteration (14.8.0 in this example). If you refer to an aggregate property (Value Group, Value List, Page Group or Page List), select a property that reside on the <CURRENT> step page of the parent's parent. (That is, the structure of the iteration must follow the structure of the page).
From within a nested iteration, you can jump (using a transition) to a labeled step that is within an outer iteration but higher numbered. You can jump from 14.8.9 to 14.10 or 17, but not from 14.8.9 to 14.3.
If a step is part of an iteration sequence, the method cannot be any of the following:
Connect-Java Obj-Open Obj-Open-By-Handle Obj-Sort
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Page-Change-Class Page-Merge-Into Page-New Page-Validate RDB-Open |
Parameters available to called activity
PRPC automatically adds the following parameters to the parameter page of a called activity with a step that contains an iteration.
pyForEachCount
— Index of the current iteration, normally starting at 1 and incrementing by one. (If the iteration type is For Loop
, the starting value may be a value other than 1 and the increment may be a value other than 1.) This parameter is available throughout the iteration as well as in called activities.pyIterationType
— Indicates the iteration type, internally represented by one of the constants page
, embedded
, propertylist
, propertygroup
, or repeat
. (This parameter values are not available to other methods in an iteration step.)pyIterationTarget
— Identifies the name or reference of the iteration. For page and repeat types, it is blank. For embedded, it is the step page reference. For propertylist
or propertygroup
, it is the property specified in the iteration. (This parameter values are not available to other methods in an iteration step.) (This parameter values are not available to other methods in an iteration step.)pyPropertyValue
— Available only for propertylist
and propertygroup
iterations. The text value of the current property. (This parameter values are not available to other methods in an iteration step.)pyPropertyReference
— Obsolete. Set to "???" for backward compatibility.pyPropertyType
— Obsolete. Set to "???" for backward compatibility.