doc/src/snippets/code/src_script_qscriptengine.cpp
branchRCL_3
changeset 7 3f74d0d4af4c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doc/src/snippets/code/src_script_qscriptengine.cpp	Thu Apr 08 14:19:33 2010 +0300
@@ -0,0 +1,333 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+QScriptEngine myEngine;
+QScriptValue three = myEngine.evaluate("1 + 2");
+//! [0]
+
+
+//! [1]
+QScriptValue fun = myEngine.evaluate("(function(a, b) { return a + b; })");
+QScriptValueList args;
+args << 1 << 2;
+QScriptValue threeAgain = fun.call(QScriptValue(), args);
+//! [1]
+
+
+//! [2]
+QString fileName = "helloworld.qs";
+QFile scriptFile(fileName);
+if (!scriptFile.open(QIODevice::ReadOnly))
+    // handle error
+QTextStream stream(&scriptFile);
+QString contents = stream.readAll();
+scriptFile.close();
+myEngine.evaluate(contents, fileName);
+//! [2]
+
+
+//! [3]
+myEngine.globalObject().setProperty("myNumber", 123);
+...
+QScriptValue myNumberPlusOne = myEngine.evaluate("myNumber + 1");
+//! [3]
+
+
+//! [4]
+QScriptValue result = myEngine.evaluate(...);
+if (myEngine.hasUncaughtException()) {
+    int line = myEngine.uncaughtExceptionLineNumber();
+    qDebug() << "uncaught exception at line" << line << ":" << result.toString();
+}
+//! [4]
+
+
+//! [5]
+QPushButton button;
+QScriptValue scriptButton = myEngine.newQObject(&button);
+myEngine.globalObject().setProperty("button", scriptButton);
+
+myEngine.evaluate("button.checkable = true");
+
+qDebug() << scriptButton.property("checkable").toBoolean();
+scriptButton.property("show").call(); // call the show() slot
+//! [5]
+
+
+//! [6]
+QScriptValue myAdd(QScriptContext *context, QScriptEngine *engine)
+{
+   QScriptValue a = context->argument(0);
+   QScriptValue b = context->argument(1);
+   return a.toNumber() + b.toNumber();
+}
+//! [6]
+
+
+//! [7]
+QScriptValue fun = myEngine.newFunction(myAdd);
+myEngine.globalObject().setProperty("myAdd", fun);
+//! [7]
+
+
+//! [8]
+QScriptValue result = myEngine.evaluate("myAdd(myNumber, 1)");
+//! [8]
+
+
+//! [9]
+QScriptValue Foo(QScriptContext *context, QScriptEngine *engine)
+{
+    if (context->calledAsConstructor()) {
+        // initialize the new object
+        context->thisObject().setProperty("bar", ...);
+        // ...
+        // return a non-object value to indicate that the
+        // thisObject() should be the result of the "new Foo()" expression
+        return engine->undefinedValue();
+    } else {
+        // not called as "new Foo()", just "Foo()"
+        // create our own object and return that one
+        QScriptValue object = engine->newObject();
+        object.setPrototype(context->callee().property("prototype"));
+        object.setProperty("baz", ...);
+        return object;
+    }
+}
+
+...
+
+QScriptValue fooProto = engine->newObject();
+fooProto.setProperty("whatever", ...);
+engine->globalObject().setProperty("Foo", engine->newFunction(Foo, fooProto));
+//! [9]
+
+
+//! [10]
+class Bar { ... };
+
+Q_DECLARE_METATYPE(Bar)
+
+QScriptValue constructBar(QScriptContext *context, QScriptEngine *engine)
+{
+    Bar bar;
+    // initialize from arguments in context, if desired
+    ...
+    return engine->toScriptValue(bar);
+}
+
+class BarPrototype : public QObject, public QScriptable
+{
+// provide the scriptable interface of this type using slots and properties
+...
+};
+
+...
+
+// create and register the Bar prototype and constructor in the engine
+BarPrototype *barPrototypeObject = new BarPrototype(...);
+QScriptValue barProto = engine->newQObject(barPrototypeObject);
+engine->setDefaultPrototype(qMetaTypeId<Bar>, barProto);
+QScriptValue barCtor = engine->newFunction(constructBar, barProto);
+engine->globalObject().setProperty("Bar", barCtor);
+//! [10]
+
+
+//! [11]
+static QScriptValue getSetFoo(QScriptContext *context, QScriptEngine *engine)
+{
+    QScriptValue callee = context->callee();
+    if (context->argumentCount() == 1) // writing?
+        callee.setProperty("value", context->argument(0));
+    return callee.property("value");
+}
+
+....
+
+QScriptValue object = engine.newObject();
+object.setProperty("foo", engine.newFunction(getSetFoo),
+    QScriptValue::PropertyGetter | QScriptValue::PropertySetter);
+//! [11]
+
+
+//! [12]
+QScriptValue object = engine.newObject();
+object.setProperty("foo", engine.newFunction(getFoo), QScriptValue::PropertyGetter);
+object.setProperty("foo", engine.newFunction(setFoo), QScriptValue::PropertySetter);
+//! [12]
+
+
+//! [13]
+Q_SCRIPT_DECLARE_QMETAOBJECT(QLineEdit, QWidget*)
+
+...
+
+QScriptValue lineEditClass = engine.scriptValueFromQMetaObject<QLineEdit>();
+engine.globalObject().setProperty("QLineEdit", lineEditClass);
+//! [13]
+
+
+//! [14]
+if (hello && world)
+    print("hello world");
+//! [14]
+
+
+//! [15]
+if (hello &&
+//! [15]
+
+
+//! [16]
+0 = 0
+//! [16]
+
+
+//! [17]
+./test.js
+//! [17]
+
+
+//! [18]
+foo["bar"]
+//! [18]
+
+
+//! [19]
+QScriptEngine engine;
+QScriptContext *context = engine.pushContext();
+context->activationObject().setProperty("myArg", 123);
+engine.evaluate("var tmp = myArg + 42");
+...
+engine.popContext();
+//! [19]
+
+
+//! [20]
+struct MyStruct {
+    int x;
+    int y;
+};
+//! [20]
+
+
+//! [21]
+Q_DECLARE_METATYPE(MyStruct)
+//! [21]
+
+
+//! [22]
+QScriptValue toScriptValue(QScriptEngine *engine, const MyStruct &s)
+{
+  QScriptValue obj = engine->newObject();
+  obj.setProperty("x", s.x);
+  obj.setProperty("y", s.y);
+  return obj;
+}
+
+void fromScriptValue(const QScriptValue &obj, MyStruct &s)
+{
+  s.x = obj.property("x").toInt32();
+  s.y = obj.property("y").toInt32();
+}
+//! [22]
+
+
+//! [23]
+qScriptRegisterMetaType(engine, toScriptValue, fromScriptValue);
+//! [23]
+
+
+//! [24]
+MyStruct s = qscriptvalue_cast<MyStruct>(context->argument(0));
+...
+MyStruct s2;
+s2.x = s.x + 10;
+s2.y = s.y + 20;
+QScriptValue v = engine->toScriptValue(s2);
+//! [24]
+
+
+//! [25]
+QScriptValue createMyStruct(QScriptContext *, QScriptEngine *engine)
+{
+    MyStruct s;
+    s.x = 123;
+    s.y = 456;
+    return engine->toScriptValue(s);
+}
+...
+QScriptValue ctor = engine.newFunction(createMyStruct);
+engine.globalObject().setProperty("MyStruct", ctor);
+//! [25]
+
+
+//! [26]
+Q_DECLARE_METATYPE(QVector<int>)
+
+...
+
+qScriptRegisterSequenceMetaType<QVector<int> >(engine);
+...
+QVector<int> v = qscriptvalue_cast<QVector<int> >(engine->evaluate("[5, 1, 3, 2]"));
+qSort(v.begin(), v.end());
+QScriptValue a = engine->toScriptValue(v);
+qDebug() << a.toString(); // outputs "[1, 2, 3, 5]"
+//! [26]
+
+//! [27]
+QScriptValue mySpecialQObjectConstructor(QScriptContext *context,
+                                         QScriptEngine *engine)
+{
+    QObject *parent = context->argument(0).toQObject();
+    QObject *object = new QObject(parent);
+    return engine->newQObject(object, QScriptEngine::ScriptOwnership);
+}
+
+...
+
+QScriptValue ctor = engine.newFunction(mySpecialQObjectConstructor);
+QScriptValue metaObject = engine.newQMetaObject(&QObject::staticMetaObject, ctor);
+engine.globalObject().setProperty("QObject", metaObject);
+
+QScriptValue result = engine.evaluate("new QObject()");
+//! [27]