From 501bc44bb006ee8021cbaaa7a696e7c9263395d3 Mon Sep 17 00:00:00 2001 From: Mitch Curtis Date: Fri, 17 Apr 2020 14:32:55 +0200 Subject: Use qmlRegisterModuleImport() to register styles This patch completes the cumulative work done in previous patches. - Uses qmlRegisterModuleImport() to register styles. This has some added requirements: - Each style must now be a QML module -- that is, it must have a qmldir file. - As a result of the above, the module must be available within the QML import path in order to be found. - The various forms of accepted style names have been reduced down to one ("Material", "MyStyle", etc). See below for an explanation of why. - The following API in QQuickStyle is removed: addStylePath(), availableStyles(), path(), stylePathList(). These no longer make sense now that we reuse the existing QML import system. - Adds the tst_qquickstyleselector auto test back as "styleimports". qmlRegisterModuleImport() vs resolvedUrl() Previously we would use QQuickStyleSelector to select individual QML files based on which style was set. We'd do this once when QtQuick.Controls was first imported. With Qt 6, and the requirement that each style be a proper QML module, qmlRegisterModuleImport() was introduced. This allows us to "link" one import with another. For an example of what this looks like in practice, suppose the style was set to "MyStyle", and the fallback to "Material". The "QtQuick.Controls" import will be linked to "MyStyle", "MyStyle" to "QtQuick.Controls.Material", and as a final fallback (for controls like Action which only the Default style implements), "QtQuick.Controls.Material" to "QtQuick.Controls.Default". This is the same behavior as in Qt 5 (see qquickstyleselector.cpp): // 1) requested style (e.g. "MyStyle", included in d->selectors) // 2) fallback style (e.g. "Material", included in d->selectors) // 3) default style (empty selector, not in d->selectors) This is a necessary step to enable compilation of QML to C++. Reducing the set of accepted style names The problem In QtQuickControls2Plugin() we need to call QQuickStylePrivate::init(baseUrl()) in order to detect if the style is a custom style in QQuickStyleSpec::resolve() (by checking if the style path starts with the base URL). In Qt 5, init() is called in QtQuickControls2Plugin::registerTypes(), but in Qt 6 that's too late, because we need to call qmlRegisterModuleImport() in the constructor. qmlRegisterModuleImport() itself requires the style to have already been set in order to create the correct import URI ("QtQuick.Controls.X" for built-in styles, "MyCustomStyle" for custom styles). The solution By reducing the valid forms for style names down to one: ./myapp -style MyStyle we solve the problem of needing baseUrl() to determine if the style is a custom style or not, but needing to call it too early (since we now call qmlRegisterModuleImport() in QtQuickControls2Plugin(), which itself requires the style to have already been set). baseUrl() can't have been set before the constructor is finished. All of the various forms for _setting_ a style are still valid; environment variables, qtquickcontrols2.conf, etc. [ChangeLog][Important Behavior Changes] Custom styles must now have a qmldir that lists the files that the style implements. For example, for a style that only implements Button: --- module MyStyle Button 1.0 Button.qml --- In addition, there is now only one valid, case-sensitive form for style names: "Material", "MyStyle", etc. These changes are done to help enable the compilation of QML code to C++, as well as improve tooling capabilities. [ChangeLog][Important Behavior Changes] The following API was removed: - QQuickStyle::addStylePath() - QQuickStyle::availableStyles() - QQuickStyle::path() - QQuickStyle::stylePathList() - QT_QUICK_CONTROLS_STYLE_PATH This API is no longer necessary and/or able to be provided now that styles are treated as regular QML modules. Task-number: QTBUG-82922 Change-Id: I3b281131903c7c3c1cf0616eb7486a872dccd730 Reviewed-by: Fabian Kosmale --- examples/quickcontrols2/gallery/gallery.cpp | 6 +++++- examples/quickcontrols2/gallery/gallery.qml | 2 +- 2 files changed, 6 insertions(+), 2 deletions(-) (limited to 'examples') diff --git a/examples/quickcontrols2/gallery/gallery.cpp b/examples/quickcontrols2/gallery/gallery.cpp index b4d59685..bbcd2d14 100644 --- a/examples/quickcontrols2/gallery/gallery.cpp +++ b/examples/quickcontrols2/gallery/gallery.cpp @@ -73,7 +73,11 @@ int main(int argc, char *argv[]) QQuickStyle::setStyle(settings.value("style").toString()); QQmlApplicationEngine engine; - engine.rootContext()->setContextProperty("availableStyles", QQuickStyle::availableStyles()); + + const QStringList builtInStyles = { QLatin1String("Default"), QLatin1String("Fusion"), + QLatin1String("Imagine"), QLatin1String("Material"), QLatin1String("Universal") }; + engine.rootContext()->setContextProperty("builtInStyles", builtInStyles); + engine.load(QUrl("qrc:/gallery.qml")); if (engine.rootObjects().isEmpty()) return -1; diff --git a/examples/quickcontrols2/gallery/gallery.qml b/examples/quickcontrols2/gallery/gallery.qml index f76315cc..872bdb44 100644 --- a/examples/quickcontrols2/gallery/gallery.qml +++ b/examples/quickcontrols2/gallery/gallery.qml @@ -287,7 +287,7 @@ ApplicationWindow { ComboBox { id: styleBox property int styleIndex: -1 - model: availableStyles + model: builtInStyles Component.onCompleted: { styleIndex = find(settings.style, Qt.MatchFixedString) if (styleIndex !== -1) -- cgit v1.2.3