20 lines
610 B
Racket
20 lines
610 B
Racket
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#lang racket/gui
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(require racket/gui/base)
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; Make a frame by instantiating the frame% class
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(define frame (new frame% [label "Goodbye, World!"]))
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; Make a static text message in the frame
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(define msg (new message% [parent frame]
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[label "No events so far..."]))
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; Make a button in the frame
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(new button% [parent frame]
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[label "Click Me"]
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; Callback procedure for a button click:
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(callback (lambda (button event)
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(send msg set-label "Button click"))))
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; Show the frame by calling its show method
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(send frame show #t)
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