EQL5/examples/M-modules/webengine/minimal.lisp

49 lines
1.4 KiB
Common Lisp

;;; simple WebEngine example
#-qt-wrapper-functions ; see README-OPTIONAL.txt
(load (in-home "src/lisp/all-wrappers"))
(qrequire :webengine)
(defvar *view* (qnew "QWebEngineView"))
;; N.B: The following functions are asynchronous (because WebEngine
;; is all asynchronous).
;;
;; So, we won't have a return value, but need to pass a function.
;; (See 'FunctorOrLambda' in both Qt Assistant and EQL sources.)
(defun to-text ()
(|toPlainText| (|page| *view*)
(lambda (text) (print text))))
(defun js (expression)
;; example: (js "document.title")
(|runJavaScript| (|page| *view*) expression
(lambda (result) (qmsg result))))
;; Introducing macro SYNCALL allows to call asynchronous functions
;; as if they were synchronous (more convenient in simple cases).
(defmacro syncall (expression)
"Converts asynchronous function calls to synchronous ones, using a local event loop."
(let ((result (gensym))
(ev-loop (gensym)))
`(let (,result)
(qlet ((,ev-loop "QEventLoop"))
(,@expression (lambda (x)
(setf ,result x)
(|exit| ,ev-loop)))
(|exec| ,ev-loop))
,result)))
(defun to-text* ()
(print (syncall (|toPlainText| (|page| *view*)))))
(defun js* (expression)
(qmsg (syncall (|runJavaScript| (|page| *view*) expression))))
(x:do-with *view*
(|setUrl| (qnew "QUrl(QString)" "http://planet.lisp.org/"))
(|resize| '(800 600))
(|show|))