different way to switch activities

limit usage of MouseEventListener to make
things less glitchy

shell/contents/views/ActivityHandle.qml

@@ -0,0 +1,87 @@
+/*
+ *   Copyright 2014 Aaron Seigo <aseigo@kde.org>
+ *   Copyright 2017 Marco Martin <notmart@gmail.com>
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU Library General Public License as
+ *   published by the Free Software Foundation; either version 2, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU Library General Public License for more details
+ *
+ *   You should have received a copy of the GNU Library General Public
+ *   License along with this program; if not, write to the
+ *   Free Software Foundation, Inc.,
+ *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+import QtQuick 2.6
+import org.kde.plasma.core 2.0 as PlasmaCore
+import org.kde.plasma.components 2.0 as PlasmaComponents
+
+MouseArea {
+    id: handle
+    z: 999
+
+    property bool mirrored: false
+    anchors {
+        top: parent.top
+        bottom: parent.bottom
+        right: handle.mirrored ? parent.right : undefined
+        left: handle.mirrored ? undefined : parent.left
+    }
+    width: units.gridUnit
+    drag.target: nextActivityLabel
+    drag.axis: Drag.XAxis
+    property real position: (mirrored ? -1 : 1) * (nextActivityLabel.x + nextActivityLabel.width/2) / (parent.width/2)
+    PlasmaCore.FrameSvgItem {
+        id: nextActivityLabel
+        anchors.verticalCenter: parent.verticalCenter
+        x: handle.mirrored ? handle.width : -width
+        opacity: parent.position
+        imagePath: "widgets/background"
+        width: childrenRect.width + units.gridUnit*2
+        height: childrenRect.height + units.gridUnit*2
+        PlasmaComponents.Label {
+            anchors.centerIn: parent
+            text: handle.mirrored ? i18n("Go To Next Activity") : i18n("Go To Previous Activity")
+        }
+    }
+    onPressed: {
+        nextActivityLabel.x = handle.mirrored ? handle.width : -nextActivityLabel.width
+    }
+    onReleased: {
+        if (position > 0.5) {
+            if (handle.mirrored) {
+                root.containmentsEnterFromRight = true;
+                activitiesRepresentation.incrementCurrentIndex();
+            } else {
+                root.containmentsEnterFromRight = false;
+                activitiesRepresentation.decrementCurrentIndex();
+            }
+            acceptAnim.running = true;
+        } else {
+            dismissAnim.running = true;
+        }
+    }
+    OpacityAnimator {
+        id: acceptAnim
+        target: nextActivityLabel
+        from: nextActivityLabel.opacity
+        to: 0
+        duration: units.longDuration
+        easing.type: Easing.InOutQuad
+    }
+    XAnimator {
+        id: dismissAnim
+        target: nextActivityLabel
+        from: nextActivityLabel.x
+        to: handle.mirrored ? 0 : -nextActivityLabel.width
+        duration: units.longDuration
+        easing.type: Easing.InOutQuad
+    }
+}
+

shell/contents/views/Desktop.qml

@@ -18,7 +18,7 @@
  *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  */
 
-import QtQuick 2.0
+import QtQuick 2.6
 import QtGraphicalEffects 1.0
 import org.kde.plasma.core 2.0 as PlasmaCore
 import org.kde.plasma.shell 2.0 as Shell
@@ -28,7 +28,7 @@ import org.kde.kquickcontrolsaddons 2.0
 import org.kde.activities 0.1 as Activities
 import "../components"
 
-MouseEventListener {
+Item {
     id: root
     width: 1080
     height: 1920
@@ -59,24 +59,14 @@ MouseEventListener {
             }
         }
     }
-    property int mouseDownX
-    property int mouseDownY
-    onPressed: {
-        mouseDownX = mouse.x
-        mouseDownY = mouse.y
+
+    ActivityHandle {
+        mirrored: true
     }
-    onReleased: {
-        if (Math.abs(mouse.x - mouseDownX) < Math.abs(mouse.y - mouseDownY)) {
-            return;
-        }
-        if (mouse.x - mouseDownX > root.width/6) {
-            root.containmentsEnterFromRight = false;
-            activitiesRepresentation.decrementCurrentIndex();
-        } else if (mouse.x - mouseDownX < -root.width/6) {
-            root.containmentsEnterFromRight = true;
-            activitiesRepresentation.incrementCurrentIndex();
-        }
+    ActivityHandle {
+        mirrored: false
     }
+
     function toggleWidgetExplorer(containment) {
         console.log("Widget Explorer toggled");
         if (widgetExplorerStack.source != "") {