0.0.1
Copyright © 2009 Tobias Rautenkranz
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
Abstract
Common Lisp bindings for Qt and KDE using Smoke.
Table of Contents
List of Examples
Table of Contents
CL-Smoke provides CLOS bindings for the Qt and KDE libraries.
CommonQt (No CLOS, no startup overhead)
Lisp-CFFI-Qt4 (dead)
Ownership transfer to / from C++ of non QObject objects is seldom known to cl-smoke. E.g.: cl-smoke might delete an instance even though it is still needed by C++. (One that is known is QUndoStack::push().)
Limited conversions to and from C++. You will get an NO-APPLICABLE-CXX-METHOD error when a Lisp to C++ conversion is missing and a pointer will be returned when there is no C++ to Lisp conversion.
6 seconds startup time[1] (for qt.examples) on a Pentium M 1.7GHz.
Needs to be recompiled when the Smoke library is updated.
Could be faster
Method calling is near 3000 times slower than native C++. The overhead is mainly in the overload
resolution and to/from foreign object translation. Some measurements by
:cl-smoke.benchmark
are in
benchmark.pdf
.
SBCL on Linux x86 (and x86_64)
Clozure CL on Linux x86.
You need to checkout the darcs repositories:
cd SOME_DIR
for r in smoke qt.core qt.gui qt.network qt.test qt.tests qt.examples qt.uitools qt.webkit qt.phonon; do
darcs get "http://tobias.rautenkranz.ch/lisp/cl-smoke/$r"
done
There are also the following repositories: qt.svg qt.dbus kde.core kde.ui kde.tests kde.examples
Build and install the :smoke and :qt.core C wrapper libraries with:
cmake ./ && make && sudo make install
in the smoke/
and qt/
directories.
When you have symlinked the .asd
system files, you
should be able to load the systems. The system name has a
:cl-smoke.
prefix. e.g.:
(asdf:oos 'asdf:load-op :cl-smoke.qt.examples)
[1] Using a core image it is around 1 second. (see the section called “Saving a Core Image”)
[2] The new smokegenerator is needed (developed by Arno Rehn for the GSOC 09).
Table of Contents
C++ names are converted to Lisp symbols by converting camelCase
to camel-case
. Underscores #\_
are replaced with
#\-
and a leading uppercase K or Q is removed.
E.g.: QHelloWorld_foo
becomes hello-world-foo
.
C++ classes have a corresponding CLOS class. The can be used like any CLOS class; E.g:
to make a QObject
instance:
(make-instance 'qt:object
)
Supply arguments as list to the :args
keyword:
(let ((parent (make-instance 'qt:object
))) (make-instance 'qt:object
:args (list parent)))
or use :arg0
, :arg1
and :arg2
.
(let ((parent (make-instance 'qt:object
))) (make-instance 'qt:object
:arg0 parent))
To extend a C++ class you have to use cxx:class
as metaclass:
(defclass my-object (qt:object
) () (:metaclasscxx:class
)) (make-instance 'my-object)
The first superclass must be a Smoke class. When you define a class that has several Smoke superclasses,
they will be constructed with their default constructor. For the first Smoke superclass you can supply arguments
with the :args
and :arg0
etc. keywords.
(defclass my-graphics-object (qt:object
qt:graphics-item
) () (:metaclasscxx:class
))
C++ methods are generic functions in the :cxx package.
The C++ method call: myInstance->frob(1);
is in Lisp:
(frob my-instance 1)
C++ style overload resolution with conversion sequences is supported. For example this:
(cxx:set-pen (make-instance 'qt:painter
) (make-instance 'qt:color
:args '("green")))
is equivalent to:
(cxx:set-pen (make-instance 'qt:painter
) "green")
In the second case a temporary qt:color
instance is implicitly created.
Instead of calling a setter method that takes no additional arguments,
(cxx:set-object-name (make-instance 'qt:object
) "foo")
you can use its setf
able getter.
(setf (cxx:object-name (make-instance 'qt:object
)) "foo")
You can extend the :cxx generic functions by
adding methods. :around
, :before
, :after
and (call-next-method)
are supported.
(defclass the-object-does-nothing (qt:object
) () (:metaclasscxx:class
)) (defmethod cxx:timer-event ((object the-object-does-nothing) event) (declare (ignore object event)) (call-next-method))
:cxx generic functions can be overload by argument count. Lambda list
keywords (e.g.: &rest
and &key
) are not supported.
Make sure you have the right number of arguments when adding a method; otherwise it will not be called.
The arguments of the method might have dynamic extend; i.e.: they are only valid in the body of the method.
Unwinding of the C++ stack is not supported. This means that you must not invoke a restart that skips any foreign function.
You will most likely encounter this problem when an error is signaled in a virtual method you have overwritten.
[3]. For this case restarts are provide that allow to return a value for the failed method,
call the default C++ implementation instead (something like #'call-next-method
) or retry.
The static C++ method QByteArray::number(int n, int base=10)
can be called by:
(qt:byte-array.number
37)
which is equivalent to the C++ code QByteArray::number(37);
.
Or with:
(cxx:number (find-class 'qt:byte-array
) 37)
or:
(cxx:number (make-instance 'qt:byte-array
) 37)
C++ Class enums available as constants. E.g.:
QColor::Rgb
is qt:color.+rgb+
.
See :cxx-support.
C++ member variables of an instance can be accessed by using slot-value
; e.g.:
(slot-value (make-instance 'qt:object) :static-meta-object)
or
(slot-value (find-class 'qt:object) :static-meta-object)
Usually they can also be accessed using methods from the :cxx package.
You should be able to use C++ Class instances like normal Lisp object.
C++ classes are automatically deleted when their Lisp object gets garbage collected;
except when they (QObjects) have a parent and thus the parent is responsible for
their deletion. When a qt:object
has a parent, a strong
reference is kept to prevent the garbage collection removing it until the parent is deleted.
Ownership transfer for non QObject instances is mostly unimplemented.
For near instant startup you can save an image. Since saving C++ instances is not supported, it is best to save the image immediately after loading the packages.
Initializing the Smoke bindings when the image is loaded is implementation dependent. It is implemented for SBCL and Clozure CL.
To save an image in SBCL you can use:
sb-ext:save-lisp-and-die
To create a bundle containing an SBCL image and the required C wrappers libraries you can use
smoke:save-bundle
.
The bundle is created using makeself.
See
make-bundle.sh in :qt.examples for an example.
To save an image in CCL
ccl:save-application
is usually used.
To allow the image to find the C wrapper libraries, they have to be installed with:
sudo make install
run in the smoke/
and qt/
directory.
Table of Contents
Besides the :cl-smoke.qt.gui there are these modules:
which provide bindings for their Qt module. The class names of this modules are in
the :qt package. (E.g. Phonon::VideoPlayer is 'qt:phonon.video-player
and QTest is 'qt:test
)
Additionally there is the :cl-smoke.qt.tests system, containing the unit tests and :cl-smoke.qt.examples for various examples.
The qt:application
object should created with:
qt:with-app. In its body the event loop can be
started with qt:exec
.
Example 3.1. Hello World
;;; Copyright 2009 Tobias Rautenkranz ;;; License: X11 license (in-package :qt.examples) (defun hello-world () "Hello world" (qt:with-app () (let ((widget (make-instance 'qt:push-button :args '("Hello world")))) (cxx:show widget) (qt:exec))))
Subclasses of qt:paint-device
(e.g. qt:widget
) can only be used when
a qt:application
instance exists. When there are, for example, qt:widget
instances
at the end of qt:with-app, they are deleted by the qt:application
destructor.
Custom cxx:paint-event
methods can use qt:with-painter
to ensure that the qt:painter
is deactivated at the end of the method.
The :cl-smoke.repl allows you to start a qt:application
event loop in the background for
interactive development in SLIME.
To start the event loop use cl-smoke.repl:start-event-loop-in-background
(or
cl-smoke.repl:start-event-loop-in-repl
).
[4]
As long as you do not kill the thread or unwind over a foreign function, you should be fine.
qt:connect connects a signal to a slot.
The signal is either a qt:qsignal
created with
qt:make-signal
or a C++ signal by using
qt:get-signal
.
The slot can be a slot returned by qt:make-slot
, a function
or a C++ slot a return from qt:get-slot
.
Example 3.2. Quit
;;; Copyright 2009 Tobias Rautenkranz ;;; License: X11 license (in-package :qt.examples) (defun hello-world-quit () "Quit on push-button click" (qt:with-app () (let ((quit (make-instance 'qt:push-button :args '("Quit"))) (font (make-instance 'qt:font :args (list "Times" 18 qt:font.+bold+)))) (cxx:resize quit 75 30) (setf (cxx:font quit) font) (qt:connect (qt:get-signal quit "pressed()") #'(lambda () (format t "About to quit()~%"))) (qt:connect (qt:get-signal quit "clicked()") (qt:get-slot (qt:app) "quit()")) (cxx:show quit) (qt:exec))))
When the argument types for a slot or signal are not specified they are determined when
the first connection is made. Note that when connecting a qt:qsignal
to a qt:qslot
at least one must have its arguments types specified. Type specifier T
allows to pass a Lisp object as is from a Lisp signal to a Lisp slot.
The functionality of the Qt SIGNAL
and SLOT
macros is
provided by qt:qsignal
and qt:qslot
.
qt:object
properties can be accessed with
qt:property
(setf-able).
The name of the property can be either a string in C++ style or a symbol in Lisp style.
The predefined Qt properties can be accessed with symbols in the keyword package.
(let ((object (make-instance 'qt:object
))) (setf (qt:property
object :object-name) "Foo") (assert (string= "Foo" (qt:property
object "objectName"))))
A qt:variant
can be constructed with qt:make-variant
or to pass a Lisp object with qt:make-lisp-variant
.
Its value is returned by qt:value.
You can use qt:tr
to translate strings.
Example 3.3. i18n Hello World
;;; Copyright 2009 Tobias Rautenkranz ;;; License: X11 license (in-package :qt.examples) (defun i18n-hello-world () "i18n hello world" (qt:with-app () (qt:with-translator ("hello-world" *default-pathname-defaults* *source-path*) (let ((widget (make-instance 'qt:label))) (setf (cxx:window-title widget) (qt:tr "Lisp Qt Example" "hello-world") (cxx:text widget) (format nil (qt:tr "<h1>Hello world</h1> You are running ~A version ~A on a ~A ~A") (lisp-implementation-type) (lisp-implementation-version) (software-type) (software-version))) (cxx:show widget) (qt:exec))))) ;; FIXME: ;; calling #'software-version from the qt:application event loop ;; segfaults in SBCL. The first call caches the result in ;; sb-sys::*software-version* and we thus prevent the crash in ;; (run-program "/bin/uname" [...]). #+sbcl (smoke:eval-startup (:load-toplevel) (software-version))
hello-world_de.po
.
# Copyright (C) YEAR THE PACKAGE'S COPYRIGHT HOLDER # This file is distributed under the same license as the PACKAGE package. # # Tobias Rautenkranz <tobias@rautenkranz.ch>, 2009. msgid "" msgstr "" "Project-Id-Version: hello-world\n" "Report-Msgid-Bugs-To: \n" "POT-Creation-Date: 2009-07-01 01:17+0200\n" "PO-Revision-Date: 2009-03-21 11:41+0100\n" "Last-Translator: Tobias Rautenkranz <tobias@rautenkranz.ch>\n" "Language-Team: German <>\n" "MIME-Version: 1.0\n" "Content-Type: text/plain; charset=UTF-8\n" "Content-Transfer-Encoding: 8bit\n" "X-Generator: Lokalize 0.3\n" "Plural-Forms: nplurals=2; plural=n != 1;\n" #: i18n-hello-world.lisp:21 msgctxt "hello-world" msgid "Lisp Qt Example" msgstr "Lisp Qt Beispiel" #: i18n-hello-world.lisp:22 #, lisp-format msgid "" "<h1>Hello world</h1>\n" "\n" "You are running ~A version ~A on a ~A ~A" msgstr "" "<h1>Hallo Welt</h1>\n" "\n" "Du verwendest, auf ~2@*~A ~A, ~0@*~A version ~A"
Gettext is used to extract the i18n strings and compile the message catalog.
See CMakeLists.txt
and UseClQti18n.cmake
in the src/
directory of :cl-smoke.qt.examples on how to do this.
You can run the examples with:
(asdf:oos 'asdf:load-op :cl-smoke.qt.examples)
(qt.examples:launcher
)
Example 3.4. Repl
Use a qt:string-list-model
with a qt:list-view
to show evaluated lisp expressions.
;;; Copyright 2009 Tobias Rautenkranz ;;; License: X11 license (in-package :qt.examples) (defclass repl (qt:widget) ((model :reader model :initform (make-instance 'qt:string-list-model)) (output :reader output :initform (make-instance 'qt:list-view)) (input :reader input :initform (make-instance 'qt:line-edit))) (:metaclass cxx:class)) (defun append-list-model (list-model string) "Appends STRING to LIST-MODEL." (let ((index (cxx:row-count list-model))) (unless (cxx:insert-row list-model index) (error "insert-row ~A for ~A failed." index list-model)) (unless (cxx:set-data list-model (cxx:index list-model index) string) (error "set-data failed.")))) (defmethod initialize-instance :after ((repl repl) &rest args) (declare (ignore args)) (setf (cxx:model (output repl)) (model repl)) (qt:connect (qt:get-signal (input repl) "returnPressed()") #'(lambda () (append-list-model ;; Input (model repl) (format nil "> ~A" (cxx:text (input repl)))) (append-list-model ;; return value (model repl) (write-to-string (handler-case (eval (read-from-string (cxx:text (input repl)))) (error (condition) condition)))) (cxx:clear (input repl)))) (let ((layout (make-instance 'qt:vbox-layout))) (cxx:add-widget layout (output repl)) (cxx:add-widget layout (input repl)) (setf (cxx:layout repl) layout)) (cxx:set-focus (input repl))) (defun repl () "Lisp REPL" (qt:with-app () (let ((repl (make-instance 'repl))) (cxx:show repl) (qt:exec))))
Example 3.5. Class Browser
Qt Classes browser using :cl-smoke.qt.webkit to display the
API doc and a custom qt:list-model
for the qt:list-view
of the available classes.
;;; Copyright 2009 Tobias Rautenkranz ;;; License: X11 license (in-package :qt.examples) (defclass classes-model (qt:abstract-list-model) ((items :reader items :initarg :items :initform (make-array 0 :adjustable t :fill-pointer t))) (:metaclass cxx:class)) (defmethod cxx:row-count ((list classes-model) parent) (length (items list))) (defmethod cxx:data ((list classes-model) index role) (if (and (cxx:is-valid index) (< (cxx:row index) (length (items list))) (= role (value qt:+display-role+))) (string-downcase (class-name (aref (items list) (cxx:row index)))) (qt:make-variant))) (defun class-at (model-index) (aref (items (cxx:model model-index)) (cxx:row model-index))) (defclass class-browser (qt:splitter) ((classes :accessor classes :initform (make-instance 'classes-model)) (classes-list :reader classes-list :initform (make-instance 'qt:list-view)) (info :reader class-info :initform (make-instance 'qt:label)) (web-view :reader web-view :initform (make-instance 'qt:web-view))) (:metaclass cxx:class)) (defun setup-class-list (classes) (do-external-symbols (symbol :qt) (let ((class (find-class symbol nil))) (when (and (not (null class)) (typep class (find-class 'smoke::smoke-standard-class))) (vector-push-extend class (items classes))))) (sort (items classes) #'(lambda (class1 class2) (string< (class-name class1) (class-name class2))))) (defmethod initialize-instance :after ((browser class-browser) &rest args) (declare (ignore args)) (let* ((w (make-instance 'qt:widget)) (layout (make-instance 'qt:vbox-layout))) (cxx:add-widget layout (classes-list browser)) (let ((search (make-instance 'qt:line-edit))) (cxx:add-widget layout search) (qt:connect (qt:get-signal search "textChanged(QString)") #'(lambda (text) ;; FIXME since the class list is sorted we could do better (cxx:keyboard-search (classes-list browser) text)))) (let ((scroll (make-instance 'qt:scroll-area))) (setf (cxx:widget scroll) (class-info browser) (cxx:widget-resizable scroll) t) (cxx:add-widget layout scroll)) (setf (cxx:layout w) layout) (cxx:add-widget browser w)) (cxx:add-widget browser (web-view browser)) (qt:do-delayed-initialize (setup-class-list (classes browser)) (setf (cxx:uniform-item-sizes (classes-list browser)) t (cxx:selection-mode (classes-list browser)) qt:abstract-item-view.+single-selection+ (cxx:model (classes-list browser)) (classes browser) (cxx:word-wrap (class-info browser)) t (cxx:window-title browser) "CL Qt Classes") (qt:connect (qt:get-signal (cxx:selection-model (classes-list browser)) "currentChanged(QModelIndex, QModelIndex)") #'(lambda (current previous) (declare (ignore previous)) (set-info (class-info browser) (web-view browser) current))))) (defun set-info (info web-view model-index) (let* ((class (class-at model-index))) (cxx:load web-view (format nil "http://qt.nokia.com/doc/~A/~(~A~).html" (subseq (qt:q-version) 0 3) (remove #\: (smoke:name class) :count 1))) (cxx:set-text info (format nil "<h1>qt:~A</h1> <p>~A</p> <h2>Direct Superclasses</h2> <ul> ~{ <li>~A</li> ~} </ul> <h2>Direct Subclasses</h2> <ul> ~{ <li>~A</li>~} </ul> " (string-downcase (class-name class)) (smoke:name class) (mapcar #'(lambda (c) (string-downcase (class-name c))) (closer-mop:class-direct-superclasses class)) (mapcar #'(lambda (c) (string-downcase (class-name c))) (closer-mop:class-direct-subclasses class)))))) (defun class-browser () "Qt Class Browser" (qt:with-app () (let ((browser (make-instance 'class-browser))) (cxx:show browser) (qt:exec))))
For OpenGL a binding is needed (e.g.: cl-opengl).
Example 3.6. Origami
Origami draws a pleated hyperbolic paraboloid using the method described in (Non)existence of Pleated Folds: How Paper Folds Between Creases
Axiom is needed to generate the lisp source to that calculates the vertices.
Table of Contents
To use the KDE libraries use the :cl-smoke.kde.ui (Depends on :cl-smoke.kde.core).
Besides these packages there is :kde.tests for the unit tests and :kde.examples containing the examples.
The examples can be run with:
(asdf:oos 'asdf:load-op :cl-smoke.kde.examples)
And then running the function of the example; e.g.:
(kde.examples:mandelbrot
)
Example 4.1. Hello World
;;; Copyright 2009 Tobias Rautenkranz ;;; License: X11 license (in-package :cl-smoke.kde.examples) (defun hello-world () "KDE Hello World" (kde:with-kde ("khelloworld" "Hello World" "0.1") (let* ((window (make-instance 'kde:push-button :args '("Hello world")))) (cxx:show window) (qt:exec))))
Example 4.2. KMandelbrot
A port of the Qt Mandelbrot example to KDE.
The Mandelbrot example shows how to use a worker thread to perform heavy computations without blocking the main thread's event loop.
The sources can be found in the
src/mandelbrot/
directory of the :kde.examples package
Version 1.3, 3 November 2008
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In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements”.
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If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.
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To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:
Copyright © YEAR YOUR NAME Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”.
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with… Texts.” line with this:
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If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.