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Text Callbacks

The Default settings of a Text Widget allow basic text editing facilities. However, there may be occasions when we may need greater control over things.

Several callback resources are provided for this purpose. Briefly theses are:

XmNactivateCallback
- (only single-line Text widgets) called on Enter key press.
XmNverifyCallback
- Used to verify a change to text before it made.
XmNvalueChangedCallback
- called after a change to text has been made.

XmNmotionCallback
- called when the user has altered the cursor position or made a text selection with mouse .
XmNfocusCallback
- the user wants to begin input
XmNlosingfocusCallback
- widget is losing keyboard focus.

In summary, we attach various menu, button etc. callbacks to enable various text editing, searching etc.

We can use verifyCallbacks for checking user inputs - for example for password verification.


Dave.Marshall@cm.cf.ac.uk
Tue May 24 16:52:56 BST 1994