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Message Board Parameters

The Message Board Parameters system table lets you control the width of the message board, its height, the amount of spacing between entries, the maximum number of entries, and whether or not G2 highlights new messages.

These are the class-specific attributes of the Message Board Parameters system table. The values of the first four attributes after Item-configuration are expressed in workspace units. A workspace unit is one pixel when the workspace is scaled to full size, and proportionally smaller when the workspace is scaled down. Changes to this system table do not affect existing items.

Defining the Minimum Display Interval

The Minimum-display-interval attribute defines the length of time that the message appears. If the validity interval of the antecedent of the rule is longer than the value of this attribute, that is how long the message displays. The default is indefinite.

If you set the Minimum-display-interval to 0, messages appear only for as long as they are true. However, since the validity interval for some messages can be very short, you will probably want to set a minimum display interval to give the operator time to read the message.

Class-Specific Attributes of Message Board Parameters

The class-specific attributes of the Message Board Parameters system table are:

Attribute Description
Initial-width-of-message-board
Controls the initial width of the message board. The width can change to accommodate long messages.
Allowable values:
integer
Default value:
345


Initial-height-of-message-board
Controls the initial height of the message board. The height changes if it needs to show all of the current messages.
Allowable values:
integer
Default value:
400


Spacing-between-entries
Controls the amount of vertical spacing between messages.
Allowable values:
integer
Default value:
10


Maximum-number-of-entries
Controls the maximum number of messages that can appear on a message board. After G2 reaches the limit set by this attribute, it deletes the oldest message to make room for each new message.
Allowable values:
integer
Default value:
10


Highlight-new-messages?
Controls whether G2 highlights a new message. If yes, G2 highlights each new message for the first second that it appears on the message board. If no, G2 does not highlight new messages.
Allowable values:
{yes | no}
Default value:
yes


Minimum-display-interval
Indicates how long the message should appear on the message board after an inform action.
Allowable values:
{time-interval | indefinite}
Default value:
indefinite

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