Dynapro Technologies Dynapro ET TCS, Application Developer'S Manual

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Confusion can arise from assuming that the NOCHANGE Attribute Mode prohibits changes to
attributes under all circumstances. This is not the case. The purpose of NOCHANGE Attribute
Mode is to prevent commands that indirectly call for attribute changes from having an effect, at
the same time permitting directly commanded attribute changes to occur. NOCHANGE Attribute
Mode permits attributes to be treated in a "field-like" manner rather than being associated with
characters as they are displayed.
For example, the Modify Attributes in a Region command directly calls for changes to attributes.
When the TCS receives this command, the specified attributes change, regardless of the setting
of the NOCHANGE Attribute Mode. However, when the NOCHANGE Attribute Mode is set,
actions which indirectly change displayed attributes are prohibited from changing the attributes
already displayed. An example of such an action occurs if the host sends for display any
characters which normally use the attributes previously determined by the Set Character
Attributes command. In this case, attributes associated with the newly placed characters would
remain unchanged.
To use the NOCHANGE Attribute Mode most effectively, refer to Chapter 5 of this manual,
which includes several other examples. It is important to note that directly commanded attribute
changes are not affected by this command.