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     2 **

     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

     4 ** All rights reserved.

     5 ** Contact: Nokia Corporation (qt-info@nokia.com)

     6 **

     7 ** This file is part of the documentation of the Qt Toolkit.

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     9 ** $QT_BEGIN_LICENSE:LGPL$

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    11 ** This file contains pre-release code and may not be distributed.

    12 ** You may use this file in accordance with the terms and conditions

    13 ** contained in the Technology Preview License Agreement accompanying

    14 ** this package.

    15 **

    16 ** GNU Lesser General Public License Usage

    17 ** Alternatively, this file may be used under the terms of the GNU Lesser

    18 ** General Public License version 2.1 as published by the Free Software

    19 ** Foundation and appearing in the file LICENSE.LGPL included in the

    20 ** packaging of this file.  Please review the following information to

    21 ** ensure the GNU Lesser General Public License version 2.1 requirements

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    24 ** In addition, as a special exception, Nokia gives you certain additional

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    36 **

    37 **

    38 ** $QT_END_LICENSE$

    39 **

    40 ****************************************************************************/

    41 

    42 //! [0]

    43 QScriptEngine myEngine;

    44 QScriptValue three = myEngine.evaluate("1 + 2");

    45 //! [0]

    46 

    47 

    48 //! [1]

    49 QScriptValue fun = myEngine.evaluate("function(a, b) { return a + b; }");

    50 QScriptValueList args;

    51 args << 1 << 2;

    52 QScriptValue threeAgain = fun.call(QScriptValue(), args);

    53 //! [1]

    54 

    55 

    56 //! [2]

    57 QString fileName = "helloworld.qs";

    58 QFile scriptFile(fileName);

    59 if (!scriptFile.open(QIODevice::ReadOnly))

    60     // handle error

    61 QTextStream stream(&scriptFile);

    62 QString contents = stream.readAll();

    63 scriptFile.close();

    64 myEngine.evaluate(contents, fileName);

    65 //! [2]

    66 

    67 

    68 //! [3]

    69 myEngine.globalObject().setProperty("myNumber", 123);

    70 ...

    71 QScriptValue myNumberPlusOne = myEngine.evaluate("myNumber + 1");

    72 //! [3]

    73 

    74 

    75 //! [4]

    76 QScriptValue result = myEngine.evaluate(...);

    77 if (myEngine.hasUncaughtException()) {

    78     int line = myEngine.uncaughtExceptionLineNumber();

    79     qDebug() << "uncaught exception at line" << line << ":" << result.toString();

    80 }

    81 //! [4]

    82 

    83 

    84 //! [5]

    85 QPushButton button;

    86 QScriptValue scriptButton = myEngine.newQObject(&button);

    87 myEngine.globalObject().setProperty("button", scriptButton);

    88 

    89 myEngine.evaluate("button.checkable = true");

    90 

    91 qDebug() << scriptButton.property("checkable").toBoolean();

    92 scriptButton.property("show").call(); // call the show() slot

    93 //! [5]

    94 

    95 

    96 //! [6]

    97 QScriptValue myAdd(QScriptContext *context, QScriptEngine *engine)

    98 {

    99    QScriptValue a = context->argument(0);

   100    QScriptValue b = context->argument(1);

   101    return a.toNumber() + b.toNumber();

   102 }

   103 //! [6]

   104 

   105 

   106 //! [7]

   107 QScriptValue fun = myEngine.newFunction(myAdd);

   108 myEngine.globalObject().setProperty("myAdd", fun);

   109 //! [7]

   110 

   111 

   112 //! [8]

   113 QScriptValue result = myEngine.evaluate("myAdd(myNumber, 1)");

   114 //! [8]

   115 

   116 

   117 //! [9]

   118 QScriptValue Foo(QScriptContext *context, QScriptEngine *engine)

   119 {

   120     if (context->calledAsConstructor()) {

   121         // initialize the new object

   122         context->thisObject().setProperty("bar", ...);

   123         // ...

   124         // return a non-object value to indicate that the

   125         // thisObject() should be the result of the "new Foo()" expression

   126         return engine->undefinedValue();

   127     } else {

   128         // not called as "new Foo()", just "Foo()"

   129         // create our own object and return that one

   130         QScriptValue object = engine->newObject();

   131         object.setPrototype(context->callee().property("prototype"));

   132         object.setProperty("baz", ...);

   133         return object;

   134     }

   135 }

   136 

   137 ...

   138 

   139 QScriptValue fooProto = engine->newObject();

   140 fooProto.setProperty("whatever", ...);

   141 engine->globalObject().setProperty("Foo", engine->newFunction(Foo, fooProto));

   142 //! [9]

   143 

   144 

   145 //! [10]

   146 class Bar { ... };

   147 

   148 Q_DECLARE_METATYPE(Bar)

   149 

   150 QScriptValue constructBar(QScriptContext *context, QScriptEngine *engine)

   151 {

   152     Bar bar;

   153     // initialize from arguments in context, if desired

   154     ...

   155     return engine->toScriptValue(bar);

   156 }

   157 

   158 class BarPrototype : public QObject, public QScriptable

   159 {

   160 // provide the scriptable interface of this type using slots and properties

   161 ...

   162 };

   163 

   164 ...

   165 

   166 // create and register the Bar prototype and constructor in the engine

   167 BarPrototype *barPrototypeObject = new BarPrototype(...);

   168 QScriptValue barProto = engine->newQObject(barPrototypeObject);

   169 engine->setDefaultPrototype(qMetaTypeId<Bar>, barProto);

   170 QScriptValue barCtor = engine->newFunction(constructBar, barProto);

   171 engine->globalObject().setProperty("Bar", barCtor);

   172 //! [10]

   173 

   174 

   175 //! [11]

   176 static QScriptValue getSetFoo(QScriptContext *context, QScriptEngine *engine)

   177 {

   178     QScriptValue callee = context->callee();

   179     if (context->argumentCount() == 1) // writing?

   180         callee.setProperty("value", context->argument(0));

   181     return callee.property("value");

   182 }

   183 

   184 ....

   185 

   186 QScriptValue object = engine.newObject();

   187 object.setProperty("foo", engine.newFunction(getSetFoo),

   188     QScriptValue::PropertyGetter | QScriptValue::PropertySetter);

   189 //! [11]

   190 

   191 

   192 //! [12]

   193 QScriptValue object = engine.newObject();

   194 object.setProperty("foo", engine.newFunction(getFoo), QScriptValue::PropertyGetter);

   195 object.setProperty("foo", engine.newFunction(setFoo), QScriptValue::PropertySetter);

   196 //! [12]

   197 

   198 

   199 //! [13]

   200 Q_SCRIPT_DECLARE_QMETAOBJECT(QLineEdit, QWidget*)

   201 

   202 ...

   203 

   204 QScriptValue lineEditClass = engine.scriptValueFromQMetaObject<QLineEdit>();

   205 engine.globalObject().setProperty("QLineEdit", lineEditClass);

   206 //! [13]

   207 

   208 

   209 //! [14]

   210 if (hello && world)

   211     print("hello world");

   212 //! [14]

   213 

   214 

   215 //! [15]

   216 if (hello &&

   217 //! [15]

   218 

   219 

   220 //! [16]

   221 0 = 0

   222 //! [16]

   223 

   224 

   225 //! [17]

   226 ./test.js

   227 //! [17]

   228 

   229 

   230 //! [18]

   231 foo["bar"]

   232 //! [18]

   233 

   234 

   235 //! [19]

   236 QScriptEngine engine;

   237 QScriptContext *context = engine.pushContext();

   238 context->activationObject().setProperty("myArg", 123);

   239 engine.evaluate("var tmp = myArg + 42");

   240 ...

   241 engine.popContext();

   242 //! [19]

   243 

   244 

   245 //! [20]

   246 struct MyStruct {

   247     int x;

   248     int y;

   249 };

   250 //! [20]

   251 

   252 

   253 //! [21]

   254 Q_DECLARE_METATYPE(MyStruct)

   255 //! [21]

   256 

   257 

   258 //! [22]

   259 QScriptValue toScriptValue(QScriptEngine *engine, const MyStruct &s)

   260 {

   261   QScriptValue obj = engine->newObject();

   262   obj.setProperty("x", s.x);

   263   obj.setProperty("y", s.y);

   264   return obj;

   265 }

   266 

   267 void fromScriptValue(const QScriptValue &obj, MyStruct &s)

   268 {

   269   s.x = obj.property("x").toInt32();

   270   s.y = obj.property("y").toInt32();

   271 }

   272 //! [22]

   273 

   274 

   275 //! [23]

   276 qScriptRegisterMetaType(engine, toScriptValue, fromScriptValue);

   277 //! [23]

   278 

   279 

   280 //! [24]

   281 MyStruct s = qscriptvalue_cast<MyStruct>(context->argument(0));

   282 ...

   283 MyStruct s2;

   284 s2.x = s.x + 10;

   285 s2.y = s.y + 20;

   286 QScriptValue v = engine->toScriptValue(s2);

   287 //! [24]

   288 

   289 

   290 //! [25]

   291 QScriptValue createMyStruct(QScriptContext *, QScriptEngine *engine)

   292 {

   293     MyStruct s;

   294     s.x = 123;

   295     s.y = 456;

   296     return engine->toScriptValue(s);

   297 }

   298 ...

   299 QScriptValue ctor = engine.newFunction(createMyStruct);

   300 engine.globalObject().setProperty("MyStruct", ctor);

   301 //! [25]

   302 

   303 

   304 //! [26]

   305 Q_DECLARE_METATYPE(QVector<int>)

   306 

   307 ...

   308 

   309 qScriptRegisterSequenceMetaType<QVector<int> >(engine);

   310 ...

   311 QVector<int> v = qscriptvalue_cast<QVector<int> >(engine->evaluate("[5, 1, 3, 2]"));

   312 qSort(v.begin(), v.end());

   313 QScriptValue a = engine->toScriptValue(v);

   314 qDebug() << a.toString(); // outputs "[1, 2, 3, 5]"

   315 //! [26]

   316 

   317 //! [27]

   318 QScriptValue mySpecialQObjectConstructor(QScriptContext *context,

   319                                          QScriptEngine *engine)

   320 {

   321     QObject *parent = context->argument(0).toQObject();

   322     QObject *object = new QObject(parent);

   323     return engine->newQObject(object, QScriptEngine::ScriptOwnership);

   324 }

   325 

   326 ...

   327 

   328 QScriptValue ctor = engine.newFunction(mySpecialQObjectConstructor);

   329 QScriptValue metaObject = engine.newQMetaObject(&QObject::staticMetaObject, ctor);

   330 engine.globalObject().setProperty("QObject", metaObject);

   331 

   332 QScriptValue result = engine.evaluate("new QObject()");

   333 //! [27]