2.8. Details of Edit Commands

2.8.1. Undo

When the user selects Undo from the Edit menu, the system undoes the most recently written text in the currently selected cell of the spreadsheet, or the effect of a previously executed Undo command.

2.8.2. Cut, Copy, and Paste

Operating systems typically provide a "clipboard" area through which cut and paste editing commands operate. This clipboard holds values that are cut, copied, and pasted in editable text areas in tools. The Grader's Cut, Copy, and Paste commands use the pre-provided clipboard functionality of the Operating System.

To execute the Cut or Copy command, the user is required to select some text from one of the editable text fields (i.e. the cells of the gradebook). To actually select the text, the user must either click and drag, double click, or triple click.

After text selection, when the user selects the Cut command from the Edit menu, the system removes the selected text from the edit box and copies the text into the clipboard. When the user selects the Copy command, the selected text is copied to the clipboard, but is not removed from the display in which it is selected and the text remains selected. A particular segment of selected text is unselected by selecting another text segment or by single-clicking the mouse anywhere in the Grader display. Other environment-specific means of unselecting text may be available.

The Cut command can only be used in editable text boxes, because the text is removed by the system when the user clicks the Cut command. In contrast to Cut, the Copy command can be executed in any dialog in which text boxes appear, including read-only text boxes.

To execute the Paste command, the user must first execute a Cut or Copy and then place the typing cursor within some editable text box. After these steps, when the user selects the Paste command from the Edit menu, the text stored in the clipboard is inserted at the point of the typing cursor, as if it had been entered by the user from the keyboard. Pasted text appears in normal font, i.e., it is not highlighted as selected text.

If the user attempts to execute a Cut or Copy command without first selecting text, the commands have no effect. If the user attempts to execute a Paste command without having executed either a Cut or Copy, the Paste command has no effect. The Cut, Copy, and Paste commands operate only on plain text strings within a single displayed text box. In particular, the commands do not apply to a scheduled item.

The use of the clipboard for communication between the Grader Tool and the outside operating environment depends on the capabilities of the environment. Specifically, the environment must support the insertion and removal of plain text to and from the clipboard. If this requirement is met, and the operating environment permits inter-tool clipboard communication, then plain text copied to the clipboard from a another tool can be pasted in the Calendar using Paste. Similarly, plain text cut or copied in the Grader Tool can be pasted or otherwise accessed as plain text in another tool, via the clipboard.




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