Using key strings versus ordinal item positions can greately enhance source code maintenance and readability.
Member variable XbpStatusBarPanel():key Foundation
Specifies a key string that uniquely identifies a XbpStatusBarPanel object.
The :key instance variable contains a character string that can be used to uniquely identify a panel object within its XbpStatusBar container. While the ordinal position of a statusbar panel may change as panels are added or deleted at run time, a panel's key string must be unique over the lifetime of the statusbar object. If an attempt is made to add a panel with a duplicate key string, or if the key of an existing panel is to be set to a duplicate value, a runtime value is generated.
The key string assigned to a given XbpStatusBarPanel object can be specified using the <cKey> parameter to XbpStatusBar:addItem(). Alternatively, a panel's :key instance variable may be used to change its key string after it has already been added to an XbpStatusBar instance.
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