GEOS SDK TechDocs
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1.1 Cut, Copy, and Paste
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2 Transfer Data Structures
The user can copy and move selected items without using the Edit menu; he simply drags the item using the quick-transfer button of his mouse, and the item will be either copied or moved.
There are several rules which govern whether a move or copy is taking place. The user can override these rules with a certain set of keypresses to force either a copy or move. Copy is equivalent to using the Copy and Paste functions in succession, and move is equivalent to using the Cut and Paste functions in succession.
The operation of a quick transfer (move or copy), however, depends on whether the transfer is across documents or internal to a single document. If the transfer is internal, it should become a move. If the transfer occurs across documents, it should become a copy. (Note that, for the purposes of quick-transfer, the term document is used to refer to anything the user will conceptually view as a single data holder--for example, a GeoManager "document" consists of one disk.)
Because not all documents will support a given transfer operation (for example, a text file editor can not receive a GeoDraw graphic), the user is provided with immediate feedback about the type and validity of the transfer.
For example, if a GeoDraw ellipse was selected and a quick-transfer was begun, immediately the mouse pointer would show the transfer as a move operation. As the user moves the mouse outside the GeoDraw document and into another GeoDraw document, the cursor changes to indicate a copy operation. If the user then moves the mouse over a text-only document, a "no operation," or "invalid," cursor would be shown, indicating that the ellipse could not be received.
Some applications may implement an additional feature that provides feedback to the user: modifying the source object as the type of transfer changes. For example, a drawing program may wish to alter the shape or color of an object while it is being quick-moved but leave it normal during a quick-copy or no-operation transfer.
GEOS SDK TechDocs
|
| 1.1 Cut, Copy, and Paste
| 2 Transfer Data Structures