Introduce changed signals in KDecorationOptions

For this KDecorationOptions becomes a QObject. The changed flags from
updateSettings are removed. Instead the method just emits the proper
changed signals.

This should allow better handling in the Factories.

libkdecorations/kdecoration.cpp

@@ -514,11 +514,19 @@ QString KDecorationDefines::tabDragMimeType()
     return QStringLiteral("text/ClientGroupItem");
 }
 
-KDecorationOptions::KDecorationOptions()
-    : d(new KDecorationOptionsPrivate)
+KDecorationOptions::KDecorationOptions(QObject *parent)
+    : QObject(parent)
+    , d(new KDecorationOptionsPrivate(this))
 {
     assert(KDecoration::options_ == NULL);
     KDecoration::options_ = this;
+    connect(this, &KDecorationOptions::activeFontChanged, this, &KDecorationOptions::fontsChanged);
+    connect(this, &KDecorationOptions::inactiveFontChanged, this, &KDecorationOptions::fontsChanged);
+    connect(this, &KDecorationOptions::smallActiveFontChanged, this, &KDecorationOptions::fontsChanged);
+    connect(this, &KDecorationOptions::smallInactiveFontChanged, this, &KDecorationOptions::fontsChanged);
+    connect(this, &KDecorationOptions::leftButtonsChanged, this, &KDecorationOptions::buttonsChanged);
+    connect(this, &KDecorationOptions::rightButtonsChanged, this, &KDecorationOptions::buttonsChanged);
+    connect(this, &KDecorationOptions::customButtonPositionsChanged, this, &KDecorationOptions::buttonsChanged);
 }
 
 KDecorationOptions::~KDecorationOptions()
@@ -555,9 +563,9 @@ QPalette KDecorationOptions::palette(ColorType type, bool active) const
     return(*d->pal[idx]);
 }
 
-unsigned long KDecorationOptions::updateSettings(KConfig* config)
+void KDecorationOptions::updateSettings(KConfig* config)
 {
-    return d->updateSettings(config);
+    d->updateSettings(config);
 }
 
 bool KDecorationOptions::customButtonPositions() const

libkdecorations/kdecoration.h

@@ -269,10 +269,11 @@ public:
  * It is accessible from the decorations either as KDecoration::options()
  * or KDecorationFactory::options().
  */
-class KWIN_EXPORT KDecorationOptions : public KDecorationDefines
+class KWIN_EXPORT KDecorationOptions : public QObject, public KDecorationDefines
 {
+    Q_OBJECT
 public:
-    KDecorationOptions();
+    KDecorationOptions(QObject *parent = nullptr);
     virtual ~KDecorationOptions();
     /**
      * Call to update settings when the config changes. Return value is
@@ -378,9 +379,93 @@ public:
      */
     WindowOperation operationMaxButtonClick(Qt::MouseButtons button) const;
 
+Q_SIGNALS:
     /**
-     * @internal
+     * @brief Emitted when at least one of the color settings changed.
+     *
+     * @see color
      */
+    void colorsChanged();
+    /**
+     * @brief Emitted when the active font changed.
+     *
+     * @see font
+     */
+    void activeFontChanged();
+    /**
+     * @brief Emitted when the inactive font changed.
+     *
+     * @see font
+     */
+    void inactiveFontChanged();
+    /**
+     * @brief Emitted when the small active font changed
+     *
+     * @see font
+     */
+    void smallActiveFontChanged();
+    /**
+     * @brief Emitted when the small inactive font changed
+     *
+     * @see font
+     */
+    void smallInactiveFontChanged();
+    /**
+     * @brief Emitted if any of the fonts changed.
+     *
+     * @see activeFontChanged
+     * @see inactiveFontChanged
+     * @see smallInactiveFontChanged
+     * @see smallInactiveFontChanged
+     */
+    void fontsChanged();
+    /**
+     * @brief Emitted when the left title buttons changed.
+     *
+     * @see titleButtonsLeft
+     * @see defaultTitleButtonsLeft
+     */
+    void leftButtonsChanged();
+    /**
+     * @brief Emitted when the right title buttons changed.
+     *
+     * @see titleButtonsRight
+     * @see defaultTitleButtonsRight
+     */
+    void rightButtonsChanged();
+    /**
+     * @brief Emitted when the custom buttons position setting changed.
+     *
+     * @see customButtonPositions
+     */
+    void customButtonPositionsChanged();
+    /**
+     * @brief Emitted when one of the title buttons relevant settings changed.
+     *
+     * @see leftButtonsChanged
+     * @see rightButtonsChanged
+     * @see customButtonPositionsChanged
+     */
+    void buttonsChanged();
+    /**
+     * @brief Emitted when show tooltips setting changed.
+     *
+     * @see showTooltips
+     */
+    void showTooltipsChanged();
+    /**
+     * @brief Emitted when the border size setting changed.
+     *
+     * @see preferredBorderSize
+     */
+    void borderSizeChanged();
+    /**
+     * @brief This signal is emitted whenever the configuration changed.
+     *
+     * A decoration plugin should connect to this signal and evaluate whether
+     * some decoration specific settings need to be updated.
+     */
+    void configChanged();
 
 protected:
     /** @internal */

libkdecorations/kdecoration_p.cpp

@@ -31,8 +31,9 @@ DEALINGS IN THE SOFTWARE.
 #include <QApplication>
 #include <assert.h>
 
-KDecorationOptionsPrivate::KDecorationOptionsPrivate()
-    : title_buttons_left(KDecorationOptions::defaultTitleButtonsLeft())
+KDecorationOptionsPrivate::KDecorationOptionsPrivate(KDecorationOptions *parent)
+    : q(parent)
+    , title_buttons_left(KDecorationOptions::defaultTitleButtonsLeft())
     , title_buttons_right(KDecorationOptions::defaultTitleButtonsRight())
     , custom_button_positions(false)
     , show_tooltips(true)
@@ -57,9 +58,8 @@ KDecorationOptionsPrivate::~KDecorationOptionsPrivate()
     }
 }
 
-unsigned long KDecorationOptionsPrivate::updateSettings(KConfig* config)
+void KDecorationOptionsPrivate::updateSettings(KConfig* config)
 {
-    unsigned long changed = 0;
     KConfigGroup wmConfig(config, "WM");
 
 // SettingColors
@@ -126,11 +126,17 @@ unsigned long KDecorationOptionsPrivate::updateSettings(KConfig* config)
     colors[ColorFont+NUM_COLORS] = wmConfig.readEntry("inactiveForeground",
                                    colors[ColorFont+NUM_COLORS]);
 
+    bool colorsChanged = false;
     for (int i = 0;
             i < NUM_COLORS * 2;
             ++i)
-        if (old_colors[ i ] != colors[ i ])
-            changed |= SettingColors;
+        if (old_colors[ i ] != colors[ i ]) {
+            colorsChanged = true;
+            break;
+        }
+    if (colorsChanged) {
+        emit q->colorsChanged();
+    }
 
 // SettingFont
     QFont old_activeFont = activeFont;
@@ -141,19 +147,25 @@ unsigned long KDecorationOptionsPrivate::updateSettings(KConfig* config)
     QFont activeFontGuess = QFontDatabase::systemFont(QFontDatabase::TitleFont);
 
     activeFont = wmConfig.readEntry("activeFont", activeFontGuess);
+    if (activeFont != old_activeFont) {
+        emit q->activeFontChanged();
+    }
     inactiveFont = wmConfig.readEntry("inactiveFont", activeFont);
+    if (inactiveFont != old_inactiveFont) {
+        emit q->inactiveFontChanged();
+    }
 
     activeFontSmall = activeFont;
     // TODO: Is it useful ? (Temporary hack)
     //activeFontSmall.setPointSize(activeFont.pointSize() - 2 > 0 ? activeFont.pointSize() - 2 : activeFont.pointSize()+1 );
     activeFontSmall = wmConfig.readEntry("activeFontSmall", activeFontSmall);
+    if (activeFontSmall != old_activeFontSmall) {
+        emit q->smallActiveFontChanged();
+    }
     inactiveFontSmall = wmConfig.readEntry("inactiveFontSmall", activeFontSmall);
-
-    if (old_activeFont != activeFont
-            || old_inactiveFont != inactiveFont
-            || old_activeFontSmall != activeFontSmall
-            || old_inactiveFontSmall != inactiveFontSmall)
-        changed |= SettingFont;
+    if (inactiveFontSmall != old_inactiveFontSmall) {
+        emit q->smallInactiveFontChanged();
+    }
 
     KConfigGroup styleConfig(config, "Style");
 // SettingsButtons
@@ -168,17 +180,22 @@ unsigned long KDecorationOptionsPrivate::updateSettings(KConfig* config)
         title_buttons_left  = KDecorationOptions::defaultTitleButtonsLeft();
         title_buttons_right = KDecorationOptions::defaultTitleButtonsRight();
     }
-    if (old_custom_button_positions != custom_button_positions
-            || (custom_button_positions &&
-                (old_title_buttons_left != title_buttons_left
-                 || old_title_buttons_right != title_buttons_right)))
-        changed |= SettingButtons;
+    if (old_custom_button_positions != custom_button_positions) {
+        emit q->customButtonPositionsChanged();
+    }
+    if (old_title_buttons_left != title_buttons_left) {
+        emit q->leftButtonsChanged();
+    }
+    if (old_title_buttons_right != title_buttons_right) {
+        emit q->rightButtonsChanged();
+    }
 
 // SettingTooltips
     bool old_show_tooltips = show_tooltips;
     show_tooltips = styleConfig.readEntry("ShowToolTips", true);
-    if (old_show_tooltips != show_tooltips)
-        changed |= SettingTooltips;
+    if (old_show_tooltips != show_tooltips) {
+        emit q->showTooltipsChanged();
+    }
 
 // SettingBorder
 
@@ -188,8 +205,9 @@ unsigned long KDecorationOptionsPrivate::updateSettings(KConfig* config)
         border_size = static_cast< BorderSize >(border_size_num);
     else
         border_size = BorderNormal;
-    if (old_border_size != border_size)
-        changed |= SettingBorder;
+    if (old_border_size != border_size) {
+        emit q->borderSizeChanged();
+    }
     cached_border_size = BordersCount; // invalid
 
 // destroy cached values
@@ -201,7 +219,7 @@ unsigned long KDecorationOptionsPrivate::updateSettings(KConfig* config)
         }
     }
 
-    return changed;
+    emit q->configChanged();
 }
 
 KDecorationDefines::BorderSize KDecorationOptionsPrivate::findPreferredBorderSize(BorderSize size,

libkdecorations/kdecoration_p.h

@@ -37,11 +37,12 @@ class KConfig;
 class KDecorationOptionsPrivate : public KDecorationDefines
 {
 public:
-    KDecorationOptionsPrivate();
+    KDecorationOptionsPrivate(KDecorationOptions *parent);
     ~KDecorationOptionsPrivate();
-    unsigned long updateSettings(KConfig*);   // shared implementation
+    void updateSettings(KConfig*);   // shared implementation
     BorderSize findPreferredBorderSize(BorderSize size, QList< BorderSize >) const;   // shared implementation
 
+    KDecorationOptions *q;
     QColor colors[NUM_COLORS*2];
     QPalette *pal[NUM_COLORS*2];
     QFont activeFont, inactiveFont, activeFontSmall, inactiveFontSmall;

options.cpp

@@ -107,7 +107,7 @@ int currentRefreshRate()
 }
 
 Options::Options(QObject *parent)
-    : QObject(parent)
+    : KDecorationOptions(parent)
     , m_settings(new Settings(KSharedConfig::openConfig()))
     , m_focusPolicy(ClickToFocus)
     , m_nextFocusPrefersMouse(false)

options.h

@@ -23,7 +23,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #ifndef KWIN_OPTIONS_H
 #define KWIN_OPTIONS_H
 
-#include <QObject>
 #include <kdecoration.h>
 
 #include "placement.h"
@@ -47,7 +46,7 @@ enum HiddenPreviews {
 
 class Settings;
 
-class Options : public QObject, public KDecorationOptions
+class Options : public KDecorationOptions
 {
     Q_OBJECT
     Q_ENUMS(FocusPolicy)