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3.2. Sequencing Control Modes
The Sequencing Control Modes allow the content developer to affect how navigation requests are applied to a cluster and how the cluster’s activities are considered while processing sequencing requests. Sequencing Control Modes may be applied, as needed, to constrain a desired learning experience. The control modes are used in the following ways:
During processing of a navigation request (refer to Section 4.4: Navigation Behavior) to determine whether or not the request will translate into a valid sequencing request.
During various sequencing request subprocesses (refer to Section 4.8: Sequencing Behavior) to affect how activities will be considered for delivery.
During various sequencing behaviors to affect how tracking status information is managed (refer to Section 4.2: Tracking Model).
Table 3.2a describes the Sequencing Control Modes that may be applied. Sequencing Control Modes may be applied to any activity in the activity tree, however the Sequencing Control Choice, Sequencing Control Flow and Sequencing Control Forward Only modes will have no effect if applied to leaf activities. Multiple modes can be enabled simultaneously to create combinations of control mode behaviors. In no circumstances do the control modes of one activity affect another activity – control modes are not inherited. If control modes are not explicitly defined for an activity, the default values defined in Table 3.2a will apply.
Table 3.2a: Description of Sequencing Control Modes
No. | Name | Description | Value Space | Default Value |
1 | Sequencing Control Choice | Indicates that a Choice navigation request is permitted (True or False) to target the children of the activity. | boolean | True |
2 | Sequencing Control Choice Exit | Indicates whether the activity is permitted to terminate (True or False) if a Choice navigation request is processed. | boolean | True |
3 | Sequencing Control Flow | Indicates the Flow Subprocess may be applied (True or False) to the children of this activity. | boolean | False |
4 | Sequencing Control Forward Only | Indicates that backward targets (in terms of Activity Tree traversal) are not permitted (True or False) from the children of this activity. | boolean | False |
5 | Use Current Attempt Objective Information | Indicates that the Objective Progress Information for the children of the activity will only be used (True or False) in rollup if that information was recorded during the current attempt on the activity. | boolean | True |
6 | Use Current Attempt Progress Information | Indicates that the Attempt Progress Information for the children of the activity will only be used (True or False) in rollup if that information was recorded during the current attempt on the activity. | boolean | True |
Source: IMS Simple Sequencing Behavior and Information Model [1]