Add UI language selection (flameshot-org#4249)

* Add UI language config option

* Clang format

Author: ElTh0r0

flameshot.example.ini

@@ -18,6 +18,9 @@
 ;; Default file extension for screenshots
 ;saveAsFileExtension=.png
 ;
+;; UI language (auto = detected system language)
+; uiLanguage=auto
+;
 ;; Main UI color
 ;; Color is any valid hex code or W3C color name
 ;uiColor=#740096

src/config/visualseditor.cpp

@@ -7,8 +7,10 @@
 #include "src/config/extendedslider.h"
 #include "src/config/uicoloreditor.h"
 #include "src/utils/confighandler.h"
+#include <QDirIterator>
 #include <QHBoxLayout>
 #include <QLabel>
+#include <QMessageBox>
 
 VisualsEditor::VisualsEditor(QWidget* parent)
   : QWidget(parent)
@@ -57,6 +59,8 @@ void VisualsEditor::initOpacitySlider()
 
 void VisualsEditor::initWidgets()
 {
+    initTranslations();
+
     m_tabWidget = new QTabWidget();
     m_layout->addWidget(m_tabWidget);
 
@@ -89,3 +93,55 @@ void VisualsEditor::initWidgets()
             &ButtonListView::selectAll);
     listLayout->addWidget(setAllButtons);
 }
+
+void VisualsEditor::initTranslations()
+{
+    auto* localLayout = new QHBoxLayout();
+    localLayout->addWidget(new QLabel(tr("UI language")));
+    m_selectTranslation = new QComboBox(this);
+
+    QStringList translations;
+    QString tmpFilename;
+    for (const QString& path : PathInfo::translationsPaths()) {
+        QDirIterator it(path,
+                        QStringList() << QStringLiteral("*.qm"),
+                        QDir::NoDotAndDotDot | QDir::Files);
+        while (it.hasNext()) {
+            it.next();
+            tmpFilename = it.fileName();
+
+            if (tmpFilename.startsWith(
+                  QStringLiteral("Internationalization_"))) {
+                tmpFilename =
+                  tmpFilename.remove(QStringLiteral("Internationalization_"))
+                    .remove(QStringLiteral(".qm"));
+                if (!translations.contains(tmpFilename)) {
+                    translations << tmpFilename;
+                }
+            }
+        }
+    }
+    translations.sort();
+    translations.push_front(QStringLiteral("auto"));
+    m_selectTranslation->addItems(translations);
+
+    QString language = ConfigHandler().value("uiLanguage").toString();
+    m_selectTranslation->setCurrentIndex(
+      m_selectTranslation->findText(language));
+
+    connect(m_selectTranslation,
+            &QComboBox::currentTextChanged,
+            this,
+            [this](const QString& text) {
+                ConfigHandler().setUiLanguage(text);
+                // TODO: Retranslate UI without restart
+                QMessageBox::information(
+                  this,
+                  tr("Configuration"),
+                  tr("Flameshot must be restarted to apply these changes!"));
+            });
+
+    localLayout->addWidget(m_selectTranslation);
+    localLayout->addStretch();
+    m_layout->addLayout(localLayout);
+}

src/config/visualseditor.h

@@ -3,6 +3,7 @@
 
 #pragma once
 
+#include <QComboBox>
 #include <QTabWidget>
 #include <QWidget>
 
@@ -35,6 +36,9 @@ public slots:
     ButtonListView* m_buttonList;
     ExtendedSlider* m_opacitySlider;
 
+    QComboBox* m_selectTranslation;
+
     void initWidgets();
     void initOpacitySlider();
+    void initTranslations();
 };

src/main.cpp

@@ -111,31 +111,60 @@ void configureTranslation(QTranslator& translator, QTranslator& qtTranslator)
     bool foundTranslation;
     // Configure translations
     for (const QString& path : PathInfo::translationsPaths()) {
-        foundTranslation =
-          translator.load(QLocale(),
-                          QStringLiteral("Internationalization"),
-                          QStringLiteral("_"),
-                          path);
+        if (ConfigHandler().uiLanguage() == QStringLiteral("auto")) {
+            // Load language, which was detected from the system
+            foundTranslation =
+              translator.load(QLocale(),
+                              QStringLiteral("Internationalization"),
+                              QStringLiteral("_"),
+                              path);
+        } else {
+            // Load language from settings
+            foundTranslation =
+              translator.load(QStringLiteral("Internationalization_") +
+                                ConfigHandler().uiLanguage(),
+                              path);
+        }
         if (foundTranslation) {
             break;
         }
     }
     if (!foundTranslation) {
-        QLocale l;
-        qWarning() << QStringLiteral("No Flameshot translation found for %1")
-                        .arg(l.uiLanguages().join(", "));
+        if (ConfigHandler().uiLanguage() == QStringLiteral("auto")) {
+            QLocale l;
+            qWarning() << QStringLiteral(
+                            "No Flameshot translation found for %1")
+                            .arg(l.uiLanguages().join(", "));
+        } else {
+            qWarning() << QStringLiteral(
+                            "No Flameshot translation found for %1")
+                            .arg(ConfigHandler().uiLanguage());
+        }
     }
 
-    foundTranslation =
-      qtTranslator.load(QLocale::system(),
-                        "qt",
-                        "_",
-                        QLibraryInfo::path(QLibraryInfo::TranslationsPath));
+    if (ConfigHandler().uiLanguage() == QStringLiteral("auto")) {
+        foundTranslation =
+          qtTranslator.load(QLocale::system(),
+                            "qt",
+                            "_",
+                            QLibraryInfo::path(QLibraryInfo::TranslationsPath));
+    } else {
+        foundTranslation = qtTranslator.load(
+          QStringLiteral("qt_") + ConfigHandler().uiLanguage(),
+
+          QLibraryInfo::path(QLibraryInfo::TranslationsPath));
+    }
     if (!foundTranslation) {
-        qWarning() << QStringLiteral("No Qt translation found for %1")
-                        .arg(QLocale::languageToString(
-                          QLocale::system().language()));
+        if (ConfigHandler().uiLanguage() == QStringLiteral("auto")) {
+            qWarning() << QStringLiteral("No Qt translation found for %1")
+                            .arg(QLocale::languageToString(
+                              QLocale::system().language()));
+        } else {
+            qWarning() << QStringLiteral("No Qt translation found for %1")
+                            .arg(ConfigHandler().uiLanguage());
+        }
     }
+
     qApp->installTranslator(&translator);
     qApp->installTranslator(&qtTranslator);
 }

src/utils/confighandler.cpp

@@ -107,6 +107,7 @@ static QMap<class QString, QSharedPointer<ValueHandler>>
     OPTION("uploadHistoryMax"            ,LowerBoundedInt    ( 0, 25         )),
     OPTION("undoLimit"                   ,BoundedInt         ( 0, 999, 100   )),
     // Interface tab
+    OPTION("uiLanguage"                  ,String             ( "auto"        )),
     OPTION("uiColor"                     ,Color              ( {116, 0, 150} )),
     OPTION("contrastUiColor"             ,Color              ( {39, 0, 50}   )),
     OPTION("contrastOpacity"             ,BoundedInt         ( 0, 255, 190   )),

src/utils/confighandler.h

@@ -74,6 +74,7 @@ class ConfigHandler : public QObject
     CONFIG_GETTER_SETTER(userColors, setUserColors, QVector<QColor>);
     CONFIG_GETTER_SETTER(savePath, setSavePath, QString)
     CONFIG_GETTER_SETTER(savePathFixed, setSavePathFixed, bool)
+    CONFIG_GETTER_SETTER(uiLanguage, setUiLanguage, QString)
     CONFIG_GETTER_SETTER(uiColor, setUiColor, QColor)
     CONFIG_GETTER_SETTER(contrastUiColor, setContrastUiColor, QColor)
     CONFIG_GETTER_SETTER(drawColor, setDrawColor, QColor)