Useful Procedures

procedure self
 The name of the task (which should also be the name of the parent frame widget) should be set in the global variable frame. By default the variable frame is set to the task name.
The frame title (which will be written by the window manager in the window title bar) should be set in the global variable frametitle. By default the variable frametitle is set to a null string.
The icon title (which will be used to label the icon when the window is closed) should be set in the global variable icontitle. By default the variable icontitle is set to a null string
The procedure self may have the argument frame-name which returns the frame name; the argument frame-title which returns the frame title or the argument icon-title which returns the icon title.

example of use
:frame [self frame-name] :label "[self frame-title]" :icon-name "[self icon-title]"

procedure click
 The call-back mechanism from the widgets requires that a click procedure exist. The library contains a default click procedure which may be used if the rules enforced by it are acceptable.
The frame name containing the widget is stored in the TCL global variable FRAME; the command returned is stored in the TCL global variable COMMAND and the widget returned is stored in the TCL global variable WIDGET.
If the command is :quit then the procedure click-quit is called with FRAME as an argument.
If the call-back is from WIDGET then an attempt is made to call the procedure click-widget if it exists. The number of argument in the supplied procedure is checked. Zero or one argument (to hold returned value) are acceptable. If no procedure with the name click-widget is found then an attempt is made to invoke the procedure click-default. Again zero or one arguments are acceptable. If no procedure with the name click-default is found then the call-back is logged to the diagnostic stream and ignored.

procedure click-quit
 Accepts zero or one argument (a frame widget name). The frame is iconized. The default frame is the top level frame from the application.

procedure start
 If the application is new (determined by the value of the TCL global variable started) the procedure first calls the procedure make-frame otherwise it deiconizes the frame and brings it to the front on the screen. The procedure click-redisplay is called if it exists.

procedure finish
 Destroys the frame and sets the TCL global variable started to its initial value.

A number of procedures are available which can be used to control frame widgets. By default if a frame widget name is not supplied then they act on the parent frame for the task.

procedure open-frame
 (also bring-to-front which is an alias)
Accepts an optional argument which is a frame widget name. Causes the frame to be deiconified if it is closed and the footer width to be configured using the width of the displayed frame.

procedure show-frame
 As open-frame except that the footer width is not configured. Should be used if the width of the frame may be unreliable - ie immediately after creation.

procedure close-frame
 Accepts an optional argument which is a frame widget name. The frame is iconified.

procedure destroy-frame
 Accepts an optional argument which is a frame widget name. The frame is destroyed. This is normally only done when the task is deleted or the frame is unlikely to be required again.

procedure centre-frame
 Positions the frame in the center of the screen. Accepts an optional argument which is a frame widget name.

procedure position-frame

position-frame x y [frame]
Positions the frame at the screen screen co-ordinates x y. Accepts an optional argument which is a frame widget name.

Procedures which generate general purpose dialog or transient pop-up windows.

procedure midas_dialog
 This procedure accepts the same arguments as tk_dialog which it replaces. It contains a number of implementation changes to circumvent problems in tk_dialog. The global variable dialog_wraplength (which has the default value 6I) controls the width of the dialog window.

procedure midas-warning

midas-warning msg
Creates a warning dialog pop-up window containing the text msg and a button labelled continue. The procedure returns only after a mouse click on the continue button.

procedure midas-report

midas-report msg
Creates a report dialog pop-up window containing the text msg and a button labelled OK. The procedure returns only after a mouse click on the OK button.

procedure midas-confirmation

midas-confirmation msg
Creates a confirmation dialog pop-up window containing the text msg and buttons labelled cancel and continue. The procedure returns only after a mouse click on one of the buttons. The procedure returns the value 0 if the cancel button is selected and the value 1 if the continue button is selected.

procedure midas-error

midas-error error msg
If error is not a null string then it is an error code returned by a Midas library routine. An error report is constructed using error, any text associated with error and msg. An error report dialog pop-up window containing the text generated and buttons labelled continue and abort is created. The procedure returns only after a mouse click on one of the buttons. The procedure returns the value 0 if the continue button is selected and the value 1 if the abort button is selected.

procedure display-midas-error-report

display-midas-error-report p error msg
If error is not a null string then it is an error code returned by a Midas library routine. An error report is constructed using error, any text associated with error and msg. An error report dialog pop-up window containing the text generated and buttons labelled continue and Trace Stack is created. The procedure returns only after a mouse click on one of the buttons. The procedure returns the error report text. Note that the first argument (p) is no longer used.

procedure remove-midas-error-report

remove-midas-error-report args
Retained for compatibility with previous versions. Has no current action.

procedure midas-show-file

midas-show-file file
Displays the contents of the file having path file in an information frame containing a text scroll window.

procedure midas-information

midas-information text
Displays the contents of the argument text in an information frame containing a text scroll window. This procedure should be used in preference to midas-report and midas-warning when the amount of text may be excessive for insertion in a dialog pop-up window which cannot be scrolled.

procedure midas-save-window

midas-save-window name
Normally called by the default binding to the Control+S keyboard sequence.
Permits the contents of a text or listbox window to be saved to a disc file. A browser window is started to obtain the filename to be used.
UNIX captures the window using the xgrabsc utility.

procedure midas-print-window

midas-print-window name
Normally called by the default binding to the Control+P keyboard sequence.
Permits the contents of a text or listbox window to be printed.
UNIX captures the window using the xgrabsc utility.

procedure midas-save-object

midas-save-object WIDGET
Normally called by the default binding to the Shift+Control+S keyboard sequence.
As the midas-save-window procedure except acts on the currently selected WIDGET only.

procedure midas-print-object

midas-print-object WIDGET
Normally called by the default binding to the Shift+Control+P keyboard sequence.
As the midas-print-window procedure except acts on the currently selected WIDGET only.