diff options
Diffstat (limited to 'src/qml/doc/snippets/qml/integrating-javascript/scarceresources')
3 files changed, 106 insertions, 63 deletions
diff --git a/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/avatarExample.cpp b/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/avatarExample.cpp index d74cc13d04..b41a9b4dff 100644 --- a/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/avatarExample.cpp +++ b/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/avatarExample.cpp @@ -51,84 +51,102 @@ #include "avatarExample.h" #include <QQmlEngine> #include <QQmlComponent> +#include <QGuiApplication> -void registerTypes() +struct Expectations { -//![0] - qmlRegisterType<AvatarExample>("Qt.example", 1, 0, "AvatarExample"); -//![0] -} + QQmlEngine engine; -void expectOne() -{ + void expectOne() + { //![1] -QQmlComponent component(&engine, "exampleOne.qml"); -QObject *object = component.create(); -// The scarce resource will have been released automatically -// by this point, after the binding expression was evaluated. -delete object; + QQmlComponent component(&engine, "qrc:/exampleOne.qml"); + QObject *object = component.create(); + // The scarce resource will have been released automatically + // by this point, after the binding expression was evaluated. + bool expectedResult = (object->property("avatarWidth").toInt() == 100); + delete object; //![1] -} + Q_ASSERT(expectedResult); + } -void expectTwo() -{ + void expectTwo() + { //![2] -QQmlComponent component(&engine, "exampleTwo.qml"); -QObject *object = component.create(); -// The scarce resource will not have been released automatically -// after the binding expression was evaluated. -// Since the scarce resource was not released explicitly prior -// to the binding expression being evaluated, we get: -bool expectedResult = (object->property("avatar").isValid() == true); -delete object; + QQmlComponent component(&engine, "qrc:/exampleTwo.qml"); + QObject *object = component.create(); + // The scarce resource will not have been released automatically + // after the binding expression was evaluated. + // Since the scarce resource was not released explicitly prior + // to the binding expression being evaluated, we get: + bool expectedResult = (object->property("avatar").isValid() == true); + delete object; //![2] -} + Q_ASSERT(expectedResult); + } -void expectThree() -{ + void expectThree() + { //![3] -QQmlComponent component(&engine, "exampleThree.qml"); -QObject *object = component.create(); -// The resource was preserved explicitly during evaluation of the -// JavaScript expression. Thus, during property assignment, the -// scarce resource was still valid, and so we get: -bool expectedResult = (object->property("avatar").isValid() == true); -// The scarce resource will not be released until all references to -// the resource are released, and the JavaScript garbage collector runs. -delete object; + QQmlComponent component(&engine, "qrc:/exampleThree.qml"); + QObject *object = component.create(); + // The resource was preserved explicitly during evaluation of the + // JavaScript expression. Thus, during property assignment, the + // scarce resource was still valid, and so we get: + bool expectedResult = (object->property("avatar").isValid() == true); + // The scarce resource will not be released until all references to + // the resource are released, and the JavaScript garbage collector runs. + delete object; //![3] -} + Q_ASSERT(expectedResult); + } -void expectFour() -{ + void expectFour() + { //![4] -QQmlComponent component(&engine, "exampleFour.qml"); -QObject *object = component.create(); -// The scarce resource was explicitly preserved by the client during -// the importAvatar() function, and so the scarce resource -// remains valid until the explicit call to releaseAvatar(). As such, -// we get the expected results: -bool expectedResultOne = (object->property("avatarOne").isValid() == true); -bool expectedResultTwo = (object->property("avatarTwo").isValid() == false); -// Because the scarce resource referenced by avatarTwo was released explicitly, -// it will no longer be consuming any system resources (beyond what a normal -// JS Object would; that small overhead will exist until the JS GC runs, as per -// any other JavaScript object). -delete object; + QQmlComponent component(&engine, "qrc:/exampleFour.qml"); + QObject *object = component.create(); + // The scarce resource was explicitly preserved by the client during + // the importAvatar() function, and so the scarce resource + // remains valid until the explicit call to releaseAvatar(). As such, + // we get the expected results: + bool expectedResultOne = (object->property("avatarOne").isValid() == true); + bool expectedResultTwo = (object->property("avatarTwo").isValid() == false); + // Because the scarce resource referenced by avatarTwo was released explicitly, + // it will no longer be consuming any system resources (beyond what a normal + // JS Object would; that small overhead will exist until the JS GC runs, as per + // any other JavaScript object). + delete object; //![4] -} + Q_ASSERT(expectedResultOne); + Q_ASSERT(expectedResultTwo); + } -void expectFive() -{ + void expectFive() + { //![5] -QQmlComponent component(&engine, "exampleFive.qml"); -QObject *object = component.create(); -// We have the expected results: -bool expectedResultOne = (object->property("avatarOne").isValid() == false); -bool expectedResultTwo = (object->property("avatarTwo").isValid() == false); -// Because although only avatarTwo was explicitly released, -// avatarOne and avatarTwo were referencing the same -// scarce resource. -delete object; + QQmlComponent component(&engine, "qrc:/exampleFive.qml"); + QObject *object = component.create(); + // We have the expected results: + bool expectedResultOne = (object->property("avatarOne").isValid() == false); + bool expectedResultTwo = (object->property("avatarTwo").isValid() == false); + // Because although only avatarTwo was explicitly released, + // avatarOne and avatarTwo were referencing the same + // scarce resource. + delete object; //![5] + Q_ASSERT(expectedResultOne); + Q_ASSERT(expectedResultTwo); + } +}; + +int main(int argc, char *argv[]) +{ + QGuiApplication app(argc, argv); + Expectations expectations; + expectations.expectOne(); + expectations.expectTwo(); + expectations.expectThree(); + expectations.expectFour(); + expectations.expectFive(); } diff --git a/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/avatarExample.h b/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/avatarExample.h index fb9e238512..1acc3a1c2f 100644 --- a/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/avatarExample.h +++ b/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/avatarExample.h @@ -53,6 +53,7 @@ #include <QObject> #include <QPixmap> +#include <qqml.h> //![0] // avatarExample.h @@ -60,6 +61,8 @@ class AvatarExample : public QObject { Q_OBJECT Q_PROPERTY(QPixmap avatar READ avatar WRITE setAvatar NOTIFY avatarChanged) + QML_ELEMENT + public: AvatarExample(QObject *parent = 0) : QObject(parent), m_value(100, 100) diff --git a/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/scarceresources.pro b/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/scarceresources.pro new file mode 100644 index 0000000000..d88f8f574c --- /dev/null +++ b/src/qml/doc/snippets/qml/integrating-javascript/scarceresources/scarceresources.pro @@ -0,0 +1,22 @@ +QT += qml gui + +#![0] +CONFIG += qmltypes +QML_IMPORT_NAME = Qt.example +QML_IMPORT_MAJOR_VERSION = 1 +#![0] + +RESOURCES += \ + exampleFive.qml \ + exampleFour.js \ + exampleFour.qml \ + exampleOne.qml \ + exampleThree.js \ + exampleThree.qml \ + exampleTwo.qml + +HEADERS += \ + avatarExample.h + +SOURCES += \ + avatarExample.cpp |