When the user enters data that do not meet the constraints described in the
preceding sections, the system displays an error message dialog of the general
form shown in Figure 50.
Figure 50: Generic error message dialog.
When the user attempts to add a card with a duplicate Id, the system displays the following message in the error dialog:
This error condition can arise when the user is executing either the Add or Change command. As noted in Section 2.2, there are no other constraints on field value duplication. Two or more cards may have duplicate values for any and all fields except Id.A card of the given Id is in the rolodex.
Most error conditions are the result of the user typing an illegal value in one
or more card fields. When there are multiple errors, i.e., errors in more than
one field value, an error message is displayed for each erroneous field. The
order of multiple error messages is the same as the order of fields in the
card, i.e., Name field first through Address field last. As
an example of the display for multiple error messages, Figure 51 shows the case
where the user has entered erroneous values for all five card fields.
Figure 51: Error input in all five card fields.
The card Id is the only field for which two error conditions are possible -- non-uniqueness and incorrect number of digits. These conditions are disjoint, i.e., both conditions cannot apply to the same card. Therefore, a maximum of five error messages can appear for any card.
Card fields in certain displays are read only, as described in Sections 2.3 , 2.4 , and 2.5. When the user attempts to type in a read-only field, the typing does not occur and the system produces a short audible or visible alert (e.g., "bell" sound) for each typed keystroke. The specific sound or visual cue produced for a short alert depends on the operating environment in which the Rolodex Tool is running. If the operating environment allows the user to disable the sound for an audible alert, then the sound produced by the Rolodex Tool is disabled.
Figure 52: Cannot open file.
If the user enters a file name that violates the constraints for Save
or Save As, the system responds with a dialog of the form shown in
Figure 53.
Figure 53: Cannot save file.