Add support for on-screen-message to kwineffects

Summary:
This adds support for the new on-screen-message support to the
kwineffects API and makes use of it in the colorpicker effect.

Not yet added to screenshot effect as for that we need support for
skip close animation on the on-screen-message window.

Reviewers: #plasma, #kwin

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D3803

autotests/mock_effectshandler.h

@@ -251,6 +251,11 @@ public:
     void startInteractivePositionSelection(std::function<void (const QPoint &)> callback) override {
         callback(QPoint(-1, -1));
     }
+    void showOnScreenMessage(const QString &message, const QString &iconName = QString()) override {
+        Q_UNUSED(message)
+        Q_UNUSED(iconName)
+    }
+    void hideOnScreenMessage() override {}
 
 private:
     bool m_animationsSuported = true;

effects.cpp

@@ -30,6 +30,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "client.h"
 #include "cursor.h"
 #include "group.h"
+#include "osd.h"
 #include "pointer_input.h"
 #include "scene_xrender.h"
 #include "scene_qpainter.h"
@@ -1590,6 +1591,16 @@ void EffectsHandlerImpl::startInteractivePositionSelection(std::function<void(co
     kwinApp()->platform()->startInteractivePositionSelection(callback);
 }
 
+void EffectsHandlerImpl::showOnScreenMessage(const QString &message, const QString &iconName)
+{
+    OSD::show(message, iconName);
+}
+
+void EffectsHandlerImpl::hideOnScreenMessage()
+{
+    OSD::hide();
+}
+
 //****************************************
 // EffectWindowImpl
 //****************************************

effects.h

@@ -234,6 +234,9 @@ public:
     void startInteractiveWindowSelection(std::function<void(KWin::EffectWindow*)> callback) override;
     void startInteractivePositionSelection(std::function<void(const QPoint &)> callback) override;
 
+    void showOnScreenMessage(const QString &message, const QString &iconName = QString()) override;
+    void hideOnScreenMessage() override;
+
     Scene *scene() const {
         return m_scene;
     }

effects/colorpicker/colorpicker.cpp

@@ -65,10 +65,6 @@ void ColorPickerEffect::paintScreen(int mask, QRegion region, ScreenPaintData &d
 {
     m_cachedOutputGeometry = data.outputGeometry();
     effects->paintScreen(mask, region, data);
-
-    if (m_infoFrame) {
-        m_infoFrame->render(region);
-    }
 }
 
 void ColorPickerEffect::postPaintScreen()
@@ -116,28 +112,17 @@ QColor ColorPickerEffect::pick()
 
 void ColorPickerEffect::showInfoMessage()
 {
-    if (!m_infoFrame.isNull()) {
-        return;
-    }
-    // TODO: turn the info message into a system wide service which performs hiding on mouse over
-    m_infoFrame.reset(effects->effectFrame(EffectFrameStyled, false));
-    QFont font;
-    font.setBold(true);
-    m_infoFrame->setFont(font);
-    QRect area = effects->clientArea(ScreenArea, effects->activeScreen(), effects->currentDesktop());
-    m_infoFrame->setPosition(QPoint(area.x() + area.width() / 2, area.y() + area.height() / 3));
-    m_infoFrame->setText(i18n("Select a position for color picking with left click or enter.\nEscape or right click to cancel."));
-    effects->addRepaintFull();
+    effects->showOnScreenMessage(i18n("Select a position for color picking with left click or enter.\nEscape or right click to cancel."), QStringLiteral("color-picker"));
 }
 
 void ColorPickerEffect::hideInfoMessage()
 {
-    m_infoFrame.reset();
+    effects->hideOnScreenMessage();
 }
 
 bool ColorPickerEffect::isActive() const
 {
-    return m_picking && ((m_scheduledPosition != QPoint(-1, -1)) || !m_infoFrame.isNull()) && !effects->isScreenLocked();
+    return m_picking && ((m_scheduledPosition != QPoint(-1, -1))) && !effects->isScreenLocked();
 }
 
 } // namespace

effects/colorpicker/colorpicker.h

@@ -58,7 +58,6 @@ private:
     QRect m_cachedOutputGeometry;
     QPoint m_scheduledPosition;
     bool m_picking = false;
-    QScopedPointer<EffectFrame> m_infoFrame;
 };
 
 } // namespace

libkwineffects/kwineffects.h

@@ -1229,6 +1229,23 @@ public:
      **/
     virtual void startInteractivePositionSelection(std::function<void(const QPoint &)> callback) = 0;
 
+    /**
+     * Shows an on-screen-message. To hide it again use @link{hideOnScreenMessage}.
+     *
+     * @param message The message to show
+     * @param iconName The optional themed icon name
+     * @see hideOnScreenMessage
+     * @since 5.9
+     **/
+    virtual void showOnScreenMessage(const QString &message, const QString &iconName = QString()) = 0;
+
+    /**
+     * Hides a previously shown on-screen-message again.
+     * @see showOnScreenMessage
+     * @since 5.9
+     **/
+    virtual void hideOnScreenMessage() = 0;
+
 Q_SIGNALS:
     /**
      * Signal emitted when the current desktop changed.