Add support for specifying theme, accent & primary via env

Environment values take presedence over the default values requested in
qtquickcontrols.conf, the same way than style name.

Change-Id: I4641317bdce320c33a89f3614f3c782883c9c843
Reviewed-by: Mitch Curtis <mitch.curtis@theqtcompany.com>

5 files changed, 117 insertions, 54 deletions

diff --git a/src/imports/controls/doc/src/qtquickcontrols2-material.qdoc b/src/imports/controls/doc/src/qtquickcontrols2-material.qdoc
index fb1ad081..ad807262 100644
--- a/src/imports/controls/doc/src/qtquickcontrols2-material.qdoc
+++ b/src/imports/controls/doc/src/qtquickcontrols2-material.qdoc
@@ -116,6 +116,32 @@
                 \image qtquickcontrols-material-dark.png
     \endtable
 
+    In addition to specifying the attributes in QML, it is also possible to
+    specify them via environment variables or in a \l {qtlabscontrols-conf}
+    {configuration file}.
+
+    \section3 Environment Variables
+
+    \table
+        \header
+            \li Variable
+            \li Description
+        \row
+            \li \c QT_LABS_CONTROLS_MATERIAL_THEME
+            \li The value can be one of the available \l {theme-attached-prop}{themes},
+                for example \c "Dark".
+        \row
+            \li \c QT_LABS_CONTROLS_MATERIAL_ACCENT
+            \li The value can be any \l {colorbasictypedocs}{color}, but it is recommended
+                to use one of the \l {Pre-defined Colors}{pre-defined colors}, for example
+                for example \c "Teal".
+        \row
+            \li \c QT_LABS_CONTROLS_MATERIAL_PRIMARY
+            \li The value can be any \l {colorbasictypedocs}{color}, but it is recommended
+                to use one of the \l {Pre-defined Colors}{pre-defined colors}, for example
+                for example \c "BlueGrey".
+    \endtable
+
     \section2 Dependency
 
     The Material style must be separately imported to gain access to the
diff --git a/src/imports/controls/doc/src/qtquickcontrols2-styles.qdoc b/src/imports/controls/doc/src/qtquickcontrols2-styles.qdoc
index 166edd45..a4f036e6 100644
--- a/src/imports/controls/doc/src/qtquickcontrols2-styles.qdoc
+++ b/src/imports/controls/doc/src/qtquickcontrols2-styles.qdoc
@@ -92,6 +92,7 @@
     \endcode
 
     \section2 Configuration file
+    \target qtlabscontrols-conf
 
     Qt Labs Controls support a special configuration file, \c :/qtquickcontrols.conf,
     that is built into an application's resources.
diff --git a/src/imports/controls/doc/src/qtquickcontrols2-universal.qdoc b/src/imports/controls/doc/src/qtquickcontrols2-universal.qdoc
index 3943440d..78065ebd 100644
--- a/src/imports/controls/doc/src/qtquickcontrols2-universal.qdoc
+++ b/src/imports/controls/doc/src/qtquickcontrols2-universal.qdoc
@@ -116,6 +116,27 @@
                 \image qtquickcontrols-universal-dark.png
     \endtable
 
+    In addition to specifying the attributes in QML, it is also possible to
+    specify them via environment variables or in a \l {qtlabscontrols-conf}
+    {configuration file}.
+
+    \section3 Environment Variables
+
+    \table
+        \header
+            \li Variable
+            \li Description
+        \row
+            \li \c QT_LABS_CONTROLS_UNIVERSAL_THEME
+            \li The value can be one of the available \l {theme-attached-prop}{themes},
+                for example \c "Dark".
+        \row
+            \li \c QT_LABS_CONTROLS_UNIVERSAL_ACCENT
+            \li The value can be any \l {colorbasictypedocs}{color}, but it is recommended
+                to use one of the pre-defined  \l {accent-attached-prop} {accents}, for
+                example \c "Violet".
+    \endtable
+
     \section2 Dependency
 
     The Universal style must be separately imported to gain access to the
diff --git a/src/imports/controls/material/qquickmaterialstyle.cpp b/src/imports/controls/material/qquickmaterialstyle.cpp
index 9757db9f..27ffca4d 100644
--- a/src/imports/controls/material/qquickmaterialstyle.cpp
+++ b/src/imports/controls/material/qquickmaterialstyle.cpp
@@ -962,48 +962,55 @@ static Enum toEnumValue(const QByteArray &value, bool *ok)
     return static_cast<Enum>(enumeration.keyToValue(value, ok));
 }
 
+static QByteArray resolveSetting(const QByteArray &env, const QSharedPointer<QSettings> &settings, const QString &name)
+{
+    QByteArray value = qgetenv(env);
+    if (value.isNull() && !settings.isNull())
+        value = settings->value(name).toByteArray();
+    return value;
+}
+
 void QQuickMaterialStyle::init()
 {
     static bool defaultsInitialized = false;
     if (!defaultsInitialized) {
         QSharedPointer<QSettings> settings = QQuickStyleAttached::settings(QStringLiteral("Material"));
-        if (!settings.isNull()) {
-            bool ok = false;
-            QByteArray value = settings->value(QStringLiteral("Theme")).toByteArray();
-            Theme theme = toEnumValue<Theme>(value, &ok);
-            if (ok)
-                defaultTheme = m_theme = theme;
-            else if (!value.isEmpty())
-                qWarning().nospace().noquote() << settings->fileName() << ": unknown Material theme value: " << value;
-
-            value = settings->value(QStringLiteral("Primary")).toByteArray();
-            Color primary = toEnumValue<Color>(value, &ok);
-            if (ok) {
-                defaultPrimaryCustom = m_customPrimary = false;
-                defaultPrimary = m_primary = primary;
-            } else {
-                QColor color(value.constData());
-                if (color.isValid()) {
-                    defaultPrimaryCustom = m_customPrimary = true;
-                    defaultPrimary = m_primary = color.rgba();
-                } else if (!value.isEmpty()) {
-                    qWarning().nospace().noquote() << settings->fileName() << ": unknown Material primary value: " << value;
-                }
+
+        bool ok = false;
+        QByteArray themeValue = resolveSetting("QT_LABS_CONTROLS_MATERIAL_THEME", settings, QStringLiteral("Theme"));
+        Theme themeEnum = toEnumValue<Theme>(themeValue, &ok);
+        if (ok)
+            defaultTheme = m_theme = themeEnum;
+        else if (!themeValue.isEmpty())
+            qWarning().nospace().noquote() << "Material: unknown theme value: " << themeValue;
+
+        QByteArray primaryValue = resolveSetting("QT_LABS_CONTROLS_MATERIAL_PRIMARY", settings, QStringLiteral("Primary"));
+        Color primaryEnum = toEnumValue<Color>(primaryValue, &ok);
+        if (ok) {
+            defaultPrimaryCustom = m_customPrimary = false;
+            defaultPrimary = m_primary = primaryEnum;
+        } else {
+            QColor color(primaryValue.constData());
+            if (color.isValid()) {
+                defaultPrimaryCustom = m_customPrimary = true;
+                defaultPrimary = m_primary = color.rgba();
+            } else if (!primaryValue.isEmpty()) {
+                qWarning().nospace().noquote() << "Material: unknown primary value: " << primaryValue;
             }
+        }
 
-            value = settings->value(QStringLiteral("Accent")).toByteArray();
-            Color accent = toEnumValue<Color>(value, &ok);
-            if (ok) {
-                defaultAccentCustom = m_customAccent = false;
-                defaultAccent = m_accent = accent;
+        QByteArray accentValue = resolveSetting("QT_LABS_CONTROLS_MATERIAL_ACCENT", settings, QStringLiteral("Accent"));
+        Color accentEnum = toEnumValue<Color>(accentValue, &ok);
+        if (ok) {
+            defaultAccentCustom = m_customAccent = false;
+            defaultAccent = m_accent = accentEnum;
+        } else if (!accentValue.isEmpty()) {
+            QColor color(accentValue.constData());
+            if (color.isValid()) {
+                defaultAccentCustom = m_customAccent = true;
+                defaultAccent = m_accent = color.rgba();
             } else {
-                QColor color(value.constData());
-                if (color.isValid()) {
-                    defaultAccentCustom = m_customAccent = true;
-                    defaultAccent = m_accent = color.rgba();
-                } else if (!value.isEmpty()) {
-                    qWarning().nospace().noquote() << settings->fileName() << ": unknown Material accent value: " << value;
-                }
+                qWarning().nospace().noquote() << "Material: unknown accent value: " << accentValue;
             }
         }
         defaultsInitialized = true;
diff --git a/src/imports/controls/universal/qquickuniversalstyle.cpp b/src/imports/controls/universal/qquickuniversalstyle.cpp
index fb948dec..ccbdfb29 100644
--- a/src/imports/controls/universal/qquickuniversalstyle.cpp
+++ b/src/imports/controls/universal/qquickuniversalstyle.cpp
@@ -404,32 +404,40 @@ static Enum toEnumValue(const QByteArray &value, bool *ok)
     return static_cast<Enum>(enumeration.keyToValue(value, ok));
 }
 
+static QByteArray resolveSetting(const QByteArray &env, const QSharedPointer<QSettings> &settings, const QString &name)
+{
+    QByteArray value = qgetenv(env);
+    if (value.isNull() && !settings.isNull())
+        value = settings->value(name).toByteArray();
+    return value;
+}
+
 void QQuickUniversalStyle::init()
 {
     static bool defaultsInitialized = false;
     if (!defaultsInitialized) {
         QSharedPointer<QSettings> settings = QQuickStyleAttached::settings(QStringLiteral("Universal"));
-        if (!settings.isNull()) {
-            bool ok = false;
-            QByteArray value = settings->value(QStringLiteral("Theme")).toByteArray();
-            Theme theme = toEnumValue<Theme>(value, &ok);
-            if (ok)
-                DefaultTheme = m_theme = theme;
-            else if (!value.isEmpty())
-                qWarning().nospace().noquote() << settings->fileName() << ": unknown Universal theme value: " << value;
-
-            value = settings->value(QStringLiteral("Accent")).toByteArray();
-            Accent accent = toEnumValue<Accent>(value, &ok);
-            if (ok) {
-                DefaultAccent = m_accent = qquickuniversal_accent_color(accent);
-            } else {
-                QColor color(value.constData());
-                if (color.isValid())
-                    DefaultAccent = m_accent = color.rgba();
-                else if (!value.isEmpty())
-                    qWarning().nospace().noquote() << settings->fileName() << ": unknown Universal accent value: " << value;
-            }
+
+        bool ok = false;
+        QByteArray themeValue = resolveSetting("QT_LABS_CONTROLS_UNIVERSAL_THEME", settings, QStringLiteral("Theme"));
+        Theme themeEnum = toEnumValue<Theme>(themeValue, &ok);
+        if (ok)
+            DefaultTheme = m_theme = themeEnum;
+        else if (!themeValue.isEmpty())
+            qWarning().nospace().noquote() << "Universal: unknown theme value: " << themeValue;
+
+        QByteArray accentValue = resolveSetting("QT_LABS_CONTROLS_UNIVERSAL_ACCENT", settings, QStringLiteral("Accent"));
+        Accent accentEnum = toEnumValue<Accent>(accentValue, &ok);
+        if (ok) {
+            DefaultAccent = m_accent = qquickuniversal_accent_color(accentEnum);
+        } else if (!accentValue.isEmpty()) {
+            QColor color(accentValue.constData());
+            if (color.isValid())
+                DefaultAccent = m_accent = color.rgba();
+            else
+                qWarning().nospace().noquote() << "Universal: unknown accent value: " << accentValue;
         }
+
         defaultsInitialized = true;
     }