Messing around with framework GUI

Thought it would be worth uploading this small test file showcasing some application for the framework gui. I added comments to try and explain some of the functionality of how I understand some of the procedures to work.

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+#lang racket
+(require racket/gui/base)
+;;Step 1. Create a window to draw into
+(define frame(new frame% [label "Example"]))
+;;I don't know what frame% means, but new must be a procedure
+;;(send frame show #t) Running this command displays the frame
+;;send appears to be a command to be a procedure that takes a frame
+;; followed by a command and a boolean.
+;;the boolean is fed into the command in this case
+;;if you said #f it would close the window
+;;that is usefull
+;;Below is a slight expantion on example code
+;;letting the button be a toggle
+(define frame2 (new frame%[label "Example2"]))
+(define msg (new message% [parent frame2] [label " Nothing  "]))
+(define thingy #t)
+(define button-to-click (new button%
+     [parent frame2]
+     [label "Click"]
+     [callback (lambda (button event)
+                 (if thingy
+                 (begin (set! thingy #f)
+                        (send msg set-label "Something"))
+                 (begin (set! thingy #t)
+                        (send msg set-label " Nothing  "))))]))
+;;Frames are okay ish for error messages but the real stuff is
+;;in canvas stuff
+(define my-canvas%
+  (class canvas%
+    (define/override (on-event event)
+      (send msg set-label "Canvas mouse"))
+    (define/override (on-char event)
+      (send msg set-label "Canvas keyboard"))
+    (super-new)));;Don't know what that one means
+
+(define canvas-thing (new my-canvas% [parent frame2]));;unfortunately
+;;we still need to re-size it manually
+;;Now I wonder if we could create a procedure to make any text
+;;appear
+(define frame3 (new frame%[label "Example3"]))
+(define blank (new message% [parent frame3] [label "                                                                                "]))
+(define (make-text string) (begin (send blank set-label string)))
+;(send frame3 show #t)
+;(make-text "Hello World") works exactly fine.
+;;Now lets do something more complicated
+;;We want to create a procedure that creates a new line
+;;each time it is called so...
+(define frame4 (new frame%[label "Example4"]))
+;;now blank4 should be a procedure to create multiple lines in the frame
+(define (make-text-line string) (begin (new message%
+                                            [parent frame4]
+                                            [label string])))
+;;display with
+;;(send frame4 show #t)
+;;add text with
+;;(make-text-line "Hello World!")
+;;This works for not but there are a few problems
+;;first of all the window starts really small and doesn't restrict
+;;resizing. Second it is always in the middle of the frame
+;;Third, once text is on screen there is no way to get it off
+;;But we can do better
+(define frame5 (new frame%
+                   [label "Example5"]
+                   [width 300]
+                   [height 300]))
+(define canvas5 (new canvas% [parent frame5]
+             [paint-callback
+              (lambda (canvas dc)
+                (send dc set-scale 3 3)
+                (send dc set-text-foreground "blue")
+                (send dc draw-text "Don't Panic!" 0 0))]))
+;;above is the example code to write some simple text, however
+;;we can apply this to what we learned above to make something abit
+;;more
+(define frame6 (new frame%
+                    [label "Example6"]
+                    [width 600]
+                    [height 700]))
+(define (make-color-text string color)
+  (begin (new canvas%
+              [parent frame6]
+              [paint-callback
+               (lambda (canvas dc)
+                 (send dc set-text-foreground color)
+                 (send dc draw-text string 0 0 #f))])))
+;;display with
+;;(send frame6 show #t)
+;;write text with
+;;(make-color-text "Hello World!" "purple")
+;;Okay that doesn't exactly work as planned...
+;;the problem with this is that each message is it's own canvas now
+;;not only that but it means we can only print each line in it's
+;;own color. So new plan is to make it so it adds on new strings
+;;to one canvas, adding \n as nessessary. Except nevermind since
+;;\n doesn't exist in this apparently
+
+;;Lets switch back to text and we can change it later
+(define frame7 (new frame%
+                    [label "Example7"]
+                    [width 600]
+                    [height 200]))
+(define (make-blank-line i)
+  (new message%
+       [parent frame7]
+       [label "                                                                                "]))
+;;80 space characters
+;;the i is only there to make the build-list command happy
+(define Message-list (build-list 10 make-blank-line))
+;;10 make-blank-lines
+;;that build-list command is super usefull for something like this
+(define (move-down-list list)
+  (if (eq? '() (cdr list))
+      '()
+      (begin
+        (move-down-list (cdr list))
+        (send (car (cdr list)) set-label (send (car list) get-label)))))
+(define (send-word string)
+  (begin
+    (move-down-list Message-list)
+    (send (car Message-list) set-label string)))
+;;display with
+;;(send frame7 show #t)
+;;add text with
+;;(send-word "Hello World")
+;;Now using the send-word command I can make each word appear on the
+;;screen in the place where it used to be. Starting at the top of the
+;;screen and working it's way down the more text is added.
+;;on the bottom line, after adding 10 lines of text, it will remove the bottom
+;;most line
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