GEOS SDK TechDocs
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| 
1 Overview
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1.2 Quick-Transfer
Even the simplest, text-using applications provide an Edit menu with the
Cut
,
Copy
, and
Paste
options.
The Edit menu works with a hidden data area called the Clipboard . The Clipboard has no visual representation, and it can contain any format of data from text to graphics strings to custom formats defined by applications. The Clipboard's structure and implementation are completely invisible to the user beyond the functions Cut , Copy , and Paste .
The most common use of the Edit menu is within a word processor or draw program. For example, when a user wants to place a graphic from GeoDraw into GeoWrite, or when he wants to rearrange text in his NotePad, he can use the cut, copy, and paste operations.
When a user selects an item such as the word "puddle," the Cut option becomes enabled. This indicates that the user can remove the selection from the document and it will be placed on the Clipboard (anything already on the Clipboard will be replaced with the selection). When nothing is selected, the Cut option is disabled.
In order to enable the Copy option, the user must select an item, just as with Cut . Copying, however, will not remove the selection from the document--it will simply create a copy of the selection and place it on the Clipboard, removing whatever had previously been on the Clipboard.
Pasting is allowed only when something in a compatible data format is already sitting on the Clipboard. The Paste operation copies what is on the Clipboard into a document at the current insertion point (in the case of text, this is where the cursor was last placed); if something is already selected, the selection will be replaced with the pasted material. If there is nothing on the Clipboard, then there is nothing to paste; therefore, the option is disabled.
GEOS SDK TechDocs
|
| 1 Overview
| 1.2 Quick-Transfer