Tooling: Allow QML preview to change the language

Change-Id: I9afc5a0e1c7807f19dfcca1270267bbf7f718903
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

4 files changed, 56 insertions, 1 deletions

diff --git a/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewhandler.cpp b/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewhandler.cpp
index c6b28316ac..af0a2bacdc 100644
--- a/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewhandler.cpp
+++ b/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewhandler.cpp
@@ -30,6 +30,9 @@
 
 #include <QtCore/qtimer.h>
 #include <QtCore/qsettings.h>
+#include <QtCore/qlibraryinfo.h>
+#include <QtCore/qtranslator.h>
+
 #include <QtGui/qwindow.h>
 #include <QtGui/qguiapplication.h>
 #include <QtQuick/qquickwindow.h>
@@ -79,6 +82,7 @@ QQmlPreviewHandler::QQmlPreviewHandler(QObject *parent) : QObject(parent)
 
 QQmlPreviewHandler::~QQmlPreviewHandler()
 {
+    removeTranslators();
     clear();
 }
 
@@ -226,6 +230,39 @@ void QQmlPreviewHandler::zoom(qreal newFactor)
     }
 }
 
+void QQmlPreviewHandler::removeTranslators()
+{
+    if (!m_qtTranslator.isNull()) {
+        QCoreApplication::removeTranslator(m_qtTranslator.get());
+        m_qtTranslator.reset();
+    }
+
+    if (m_qmlTranslator.isNull()) {
+        QCoreApplication::removeTranslator(m_qmlTranslator.get());
+        m_qmlTranslator.reset();
+    }
+}
+
+void QQmlPreviewHandler::language(const QUrl &context, const QString &locale)
+{
+    removeTranslators();
+
+    m_qtTranslator.reset(new QTranslator(this));
+    if (m_qtTranslator->load(QLatin1String("qt_") + locale,
+                           QLibraryInfo::location(QLibraryInfo::TranslationsPath))) {
+        QCoreApplication::installTranslator(m_qtTranslator.get());
+    }
+
+    m_qmlTranslator.reset(new QTranslator(this));
+    if (m_qmlTranslator->load(QLatin1String("qml_" ) + locale,
+                              context.toLocalFile() + QLatin1String("/i18n"))) {
+        QCoreApplication::installTranslator(m_qmlTranslator.get());
+    }
+
+    for (QQmlEngine *engine : qAsConst(m_engines))
+        engine->retranslate();
+}
+
 void QQmlPreviewHandler::clear()
 {
     qDeleteAll(m_createdObjects);
diff --git a/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewhandler.h b/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewhandler.h
index 53855b0f62..6d2a77cf0b 100644
--- a/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewhandler.h
+++ b/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewhandler.h
@@ -54,6 +54,8 @@ class QQmlEngine;
 class QQuickItem;
 class QQmlPreviewUrlInterceptor;
 class QQuickWindow;
+class QTranslator;
+
 class QQmlPreviewHandler : public QObject
 {
     Q_OBJECT
@@ -67,6 +69,7 @@ public:
     void loadUrl(const QUrl &url);
     void rerun();
     void zoom(qreal newFactor);
+    void language(const QUrl &context, const QString &locale);
 
     void clear();
 
@@ -82,6 +85,7 @@ private:
     void setCurrentWindow(QQuickWindow *window);
     void frameSwapped();
     void fpsTimerHit();
+    void removeTranslators();
 
     QScopedPointer<QQuickItem> m_dummyItem;
     QList<QQmlEngine *> m_engines;
@@ -93,6 +97,9 @@ private:
 
     QTimer m_fpsTimer;
     quint16 m_frames = 0;
+
+    QScopedPointer<QTranslator> m_qtTranslator;
+    QScopedPointer<QTranslator> m_qmlTranslator;
 };
 
 QT_END_NAMESPACE
diff --git a/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewservice.cpp b/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewservice.cpp
index 5f78ce7752..b06e8e9008 100644
--- a/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewservice.cpp
+++ b/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewservice.cpp
@@ -53,6 +53,7 @@ QQmlPreviewServiceImpl::QQmlPreviewServiceImpl(QObject *parent) :
     connect(this, &QQmlPreviewServiceImpl::load, &m_handler, &QQmlPreviewHandler::loadUrl);
     connect(this, &QQmlPreviewServiceImpl::rerun, &m_handler, &QQmlPreviewHandler::rerun);
     connect(this, &QQmlPreviewServiceImpl::zoom, &m_handler, &QQmlPreviewHandler::zoom);
+    connect(this, &QQmlPreviewServiceImpl::language, &m_handler, &QQmlPreviewHandler::language);
     connect(&m_handler, &QQmlPreviewHandler::error, this, &QQmlPreviewServiceImpl::forwardError,
             Qt::DirectConnection);
     connect(&m_handler, &QQmlPreviewHandler::fps, this, &QQmlPreviewServiceImpl::forwardFps,
@@ -123,6 +124,14 @@ void QQmlPreviewServiceImpl::messageReceived(const QByteArray &data)
         emit zoom(static_cast<qreal>(factor));
         break;
     }
+    case Language: {
+        QUrl context;
+        QString locale;
+        packet >> context >> locale;
+        emit language(context.isEmpty() ? m_currentUrl : context,
+                      locale.isEmpty() ? QLocale::system().name() : locale);
+        break;
+    }
     default:
         forwardError(QString::fromLatin1("Invalid command: %1").arg(command));
         break;
diff --git a/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewservice.h b/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewservice.h
index e439b8ae69..ee59f4f3af 100644
--- a/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewservice.h
+++ b/src/plugins/qmltooling/qmldbg_preview/qqmlpreviewservice.h
@@ -62,7 +62,8 @@ public:
         Directory,
         ClearCache,
         Zoom,
-        Fps
+        Fps,
+        Language
     };
 
     static const QString s_key;
@@ -87,6 +88,7 @@ signals:
     void rerun();
     void clearCache();
     void zoom(qreal factor);
+    void language(const QUrl &context, const QString &locale);
 
 private:
     QScopedPointer<QQmlPreviewFileEngineHandler> m_fileEngine;