Text Window

There are three textwindow classes, TextWindow, BufferTextWindow and ScrollTextWindow.

textWindow [class]

  :super   xwindow 

  :slots 		 (fontid 


charwidth charheight charascent dots 


win-row-max win-col-max 


win-row win-col   ;physical current position in window 


x y


charbuf 		; for charcode conversion 


keybuf keycount 		 ;for key input


echo 


show-cursor cursor-on 		 ;boolean


kill delete 		 ;control character 


notify-object notify-method 

) 

realizes virtual terminals usable for displaying messages. The displayed contents are not buffered and there is no way to retrieve a line or a character already displayed in the TextWindow. Basically, TextWindow has similar capabilities to the dumb terminals, that are, moving the cursor, erasing lines, erasing areas, scrolling displayed texts, inserting strings, etc. Also, the text cursor can be moved to the position designated by the mouse pointer.

:init id [method]

initializes idth text-window.

creates text-window. The sizes of the window may be specified either by width and height or by rows and columns. Notify-object's notify-method is invoked when a newline character is typed in.

:cursor flag [method]

The flag can either be :on, :off or :toggle. The text cursor is addressed by the win-row and win-col. The text cursor is displayed if flag is :on, is erased if flag is :off, or is reversed if flag is :toggle. This method must be invoked frequently whenever the character at the cursor is updated.

:clear [method]

clears text-window.

:clear-eol &optional (r win-row) (c win-col) (csr :on) [method]

clears the rest of the line after the character addressed by r and c, including the character at the cursor.

:clear-lines lines &optional (r win-row) [method]

clears multiple lines after r-th row.

:clear-eos &optional (r win-row) (c win-col) [method]

clears the region after the character addressed by r and c till the end-of-the-screen.

:win-row-max [method]

returns the maximum number of lines displayable in this window.

:win-col-max [method]

returns the maximum number of columns displayable in this window.

:xy &optional (r win-row) (c win-col) [method]

calculates the pixel coordinates of the character addressed by r and c.

:goto r c &optional (cursor :on) [method]

moves the cursor to r-th row and c-th column.

:goback &optional (csr :on) [method]

moves the cursor backward by one.

:advance &optional (n 1) [method]

moves the cursor forward by n characters.

:scroll &optional (n 1) [method]

scroll textwindow vertically by n lines.

:horizontal-scroll &optional (n 1) [method]

horizontally scrolls the text by n columns.

:newline [method]

moves cursor to the beginning of the next line.

:putch ch [method]

inserts the character ch at the cursor position. The rest of the line is moved forward by one.

:putstring str &optional (e (length str)) [method]

places str at the cursor position.

:event-row event [method]

:event-col event [method]

returns the text cursor position designated by $(x, y)$ in the event.

:KeyPress event [method]

inserts the character entered at the cursor position. If the character is newline, notification is sent to the notify-object.

textWindowStream [class]

  :super   stream 

  :slots 		 (textwin) 

TextWindowStream is an output stream connected to a TextWindow. Characters or strings output to this stream by using print, format, write-byte, etc., are displayed in the textwindow. As usual file streams, the output data are buffered.

:flush [method]

flushes buffered text string and send them to the textwindow. Finish-output or writing a newline character to this stream automatically calls this method.

make-text-window-stream xwin [function]

makes text-window-stream and returns the stream object.

BufferTextWindow [class]

  :super   TextWindow 

  :slots 		 (linebuf expbuf max-line-length row col) 

maintains the line buffer representing the contents of the textwindow. Linebuf is the vector of lines. Expbuf holds tab-expanded text. Only lines displayable in the window are maintained. BufferTextWindows can be used as simple text editors which have several, often only one, lines of text. Text-item employs a BufferTextWindow as a displayable line buffer.

:line n [method]

returns the contents of the n-th line as a string.

:nlines [method]

returns number of lines in the linebuf.

:all-lines [method]

returns the linebuf, which is a vector of strings.

:refresh-line &optional (r win-row) (c win-col) [method]

redraws the r-th line after the c-th column.

:refresh &optional (start 0) [method]

redraws the lines after the start-th line inclusively.

:insert-string string [method]

inserts string at the cursor position.

:insert ch [method]

inserts the character at the cursor.

:delete n [method]

deletes n characters after the cursor.

expand-tab src &optional (offset 0) [function]

Src is a string possibly containing tabs. These tabs are replaced by spaces assuming the tab stops at every 8th position.

ScrollTextWindow [class]

  :super   BufferTextWindow 

  :slots 		 (top-row top-col   ;display-starting position 


scroll-bar-window 


horizontal-scroll-bar-window 


selected-line) 

ScrollTextWindow defines buffertextwindow with unlimited number of lines, and vertical and horizontal scroll-bars can be attached. ScrollTextWindow can handle :configureNotify event to resize itself and accompanying scroll-bar windows, and to redisplay texts. By clicking, a line can be selected.

:create &rest args &key (scroll-bar nil) (horizontal-scroll-bar nil) &allow-other-keys [method]

When scroll-bars are needed, specify T to each keyword argument.

:locate n [method]

displays the buffered text by placing the n-th line at the top of the window.

:display-selection selection [method]

Selection represents the location of the selected line. The entire seleced line is displayed highlighted.

:selection [method]

returns the selected line (string).

:read-file fname [method]

reads the textfile specified by fname into the linebuf, expands tabs, and display in the window. The cursor is put at the beginning of the screen.

:display-string strings [method]

Strings is a sequence of lines (strings). The strings are copied in the linebuf and displayed in the window.

:scroll n [method]

vertically scrolls n lines.

:horizontal-scroll n [method]

horizontally scrolls n columns.

:buttonRelease event [method]

The line where the mouse pointer is located is selected. If notification is specified when the window is created, notify-object's notify-method is invoked.

:resize w h [method]

changes the size of the window and redisplays the contents according to the new size. The same message is sent to scroll-bars if attached.