Fade out OnScreenNotification when moving with the mouse over it

Summary:
This change triggers a fade out animation when the mouse is moved over
the OnScreenNotification, thus revealing the windows underneath. When
moving the mouse out of the OnScreenNotification it gets faded in again.

This is useful for various cases, e.g. when picking a color and the pixel
one wants to pick is underneath the notification, or when trying to kill
a window...

Test Plan: Manual testing in nested setup

Reviewers: #kwin, #plasma_on_wayland

Subscribers: plasma-devel, kwin

Tags: #plasma_on_wayland, #kwin

Differential Revision: https://phabricator.kde.org/D3964

autotests/CMakeLists.txt

@@ -320,11 +320,13 @@ ecm_mark_as_test(testScreenEdges)
 set( testOnScreenNotification_SRCS
     onscreennotificationtest.cpp
     ../onscreennotification.cpp
+    ../input_event_spy.cpp
 )
 add_executable( testOnScreenNotification ${testOnScreenNotification_SRCS})
 
 target_link_libraries(testOnScreenNotification
     Qt5::Test
+    Qt5::Widgets # QAction include
     Qt5::Quick
     KF5::ConfigCore
 )

autotests/onscreennotificationtest.cpp

@@ -21,6 +21,7 @@
 
 #include "onscreennotificationtest.h"
 #include "../onscreennotification.h"
+#include "../input.h"
 
 #include <KSharedConfig>
 #include <KConfigGroup>
@@ -31,6 +32,23 @@
 
 QTEST_MAIN(OnScreenNotificationTest);
 
+namespace KWin
+{
+
+void InputRedirection::installInputEventSpy(InputEventSpy *spy)
+{
+    Q_UNUSED(spy);
+}
+
+void InputRedirection::uninstallInputEventSpy(InputEventSpy *spy)
+{
+    Q_UNUSED(spy);
+}
+
+InputRedirection *InputRedirection::s_self = nullptr;
+
+}
+
 using KWin::OnScreenNotification;
 
 void OnScreenNotificationTest::show()

onscreennotification.cpp

@@ -20,8 +20,12 @@
  */
 
 #include "onscreennotification.h"
+#include "input.h"
+#include "input_event.h"
+#include "input_event_spy.h"
 #include <config-kwin.h>
 
+#include <QPropertyAnimation>
 #include <QStandardPaths>
 #include <QTimer>
 #include <QQmlComponent>
@@ -35,6 +39,31 @@
 
 using namespace KWin;
 
+class KWin::OnScreenNotificationInputEventSpy : public InputEventSpy
+{
+public:
+    explicit OnScreenNotificationInputEventSpy(OnScreenNotification *parent);
+
+    void pointerEvent(MouseEvent *event) override;
+private:
+    OnScreenNotification *m_parent;
+};
+
+OnScreenNotificationInputEventSpy::OnScreenNotificationInputEventSpy(OnScreenNotification *parent)
+    : m_parent(parent)
+{
+}
+
+void OnScreenNotificationInputEventSpy::pointerEvent(MouseEvent *event)
+{
+    if (event->type() != QEvent::MouseMove) {
+        return;
+    }
+
+    m_parent->setContainsPointer(m_parent->geometry().contains(event->globalPos()));
+}
+
+
 OnScreenNotification::OnScreenNotification(QObject *parent)
     : QObject(parent)
     , m_timer(new QTimer(this))
@@ -47,6 +76,8 @@ OnScreenNotification::OnScreenNotification(QObject *parent)
                 show();
             } else {
                 m_timer->stop();
+                m_spy.reset();
+                m_containsPointer = false;
             }
         }
     );
@@ -131,6 +162,7 @@ void OnScreenNotification::show()
     Q_ASSERT(m_visible);
     ensureQmlContext();
     ensureQmlComponent();
+    createInputSpy();
     if (m_timer->interval() != 0) {
         m_timer->start();
     }
@@ -167,4 +199,41 @@ void OnScreenNotification::ensureQmlComponent()
     }
 }
 
+void OnScreenNotification::createInputSpy()
+{
+    Q_ASSERT(m_spy.isNull());
+    if (auto w = qobject_cast<QQuickWindow*>(m_mainItem.data())) {
+        m_spy.reset(new OnScreenNotificationInputEventSpy(this));
+        input()->installInputEventSpy(m_spy.data());
+        if (!m_animation) {
+            m_animation = new QPropertyAnimation(w, "opacity", this);
+            m_animation->setStartValue(1.0);
+            m_animation->setEndValue(0.0);
+            m_animation->setDuration(250);
+            m_animation->setEasingCurve(QEasingCurve::InOutQuad);
+        }
+    }
+}
+
+QRect OnScreenNotification::geometry() const
+{
+    if (QQuickWindow *w = qobject_cast<QQuickWindow*>(m_mainItem.data())) {
+        return w->geometry();
+    }
+    return QRect();
+}
+
+void OnScreenNotification::setContainsPointer(bool contains)
+{
+    if (m_containsPointer == contains) {
+        return;
+    }
+    m_containsPointer = contains;
+    if (!m_animation) {
+        return;
+    }
+    m_animation->setDirection(m_containsPointer ? QAbstractAnimation::Forward : QAbstractAnimation::Backward);
+    m_animation->start();
+}
+
 #include "onscreennotification.moc"

onscreennotification.h

@@ -26,6 +26,7 @@
 
 #include <KSharedConfig>
 
+class QPropertyAnimation;
 class QTimer;
 class QQmlContext;
 class QQmlComponent;
@@ -33,6 +34,8 @@ class QQmlEngine;
 
 namespace KWin {
 
+class OnScreenNotificationInputEventSpy;
+
 class OnScreenNotification : public QObject
 {
     Q_OBJECT
@@ -49,6 +52,8 @@ public:
     QString iconName() const;
     int timeout() const;
 
+    QRect geometry() const;
+
     void setVisible(bool m_visible);
     void setMessage(const QString &message);
     void setIconName(const QString &iconName);
@@ -57,6 +62,8 @@ public:
     void setConfig(KSharedConfigPtr config);
     void setEngine(QQmlEngine *engine);
 
+    void setContainsPointer(bool contains);
+
 Q_SIGNALS:
     void visibleChanged();
     void messageChanged();
@@ -67,6 +74,7 @@ private:
     void show();
     void ensureQmlContext();
     void ensureQmlComponent();
+    void createInputSpy();
     bool m_visible = false;
     QString m_message;
     QString m_iconName;
@@ -76,6 +84,9 @@ private:
     QScopedPointer<QQmlComponent> m_qmlComponent;
     QQmlEngine *m_qmlEngine = nullptr;
     QScopedPointer<QObject> m_mainItem;
+    QScopedPointer<OnScreenNotificationInputEventSpy> m_spy;
+    QPropertyAnimation *m_animation = nullptr;
+    bool m_containsPointer = false;
 };
 }