support swipe from bottom

the panel still looks the same

containments/taskpanel/package/contents/ui/Button.qml

@@ -43,4 +43,6 @@ MouseArea {
             checked = !checked;
         }
     }
+    onPositionChanged: mainMouseArea.positionChanged(mouse);
+    onReleased: mainMouseArea.released(mouse);
 }

containments/taskpanel/package/contents/ui/TaskSwitcher.qml

@@ -56,6 +56,8 @@ FullScreenPanel {
         scrollAnim.running = true;
     }
 
+    onOffsetChanged: tasksView.contentY = offset
+
     SequentialAnimation {
         id: scrollAnim
         property alias to: internalAnim.to

containments/taskpanel/package/contents/ui/main.qml

@@ -18,6 +18,7 @@
 
 import QtQuick 2.4
 import QtQuick.Layouts 1.1
+import QtQuick.Window 2.2
 
 import org.kde.plasma.plasmoid 2.0
 import org.kde.plasma.core 2.0 as PlasmaCore
@@ -33,6 +34,33 @@ PlasmaCore.ColorScope {
     TaskSwitcher {
         id: taskSwitcher
     }
+    MouseArea {
+        id: mainMouseArea
+        anchors.fill: parent
+        property int oldMouseY: 0
+        drag.filterChildren: true
+        onPressed: {
+            oldMouseY = mouse.y;
+            taskSwitcher.offset = -taskSwitcher.height
+        }
+        onPositionChanged: {
+            taskSwitcher.offset = taskSwitcher.offset - (mouse.y - oldMouseY);
+            oldMouseY = mouse.y;
+            if (taskSwitcher.visibility == Window.Hidden && taskSwitcher.offset > -taskSwitcher.height + units.gridUnit) {
+                taskSwitcher.visibility = Window.FullScreen;
+            }
+        }
+        onReleased: {
+            if (taskSwitcher.visibility == Window.Hidden) {
+                return;
+            }
+            if (taskSwitcher.offset > -taskSwitcher.height/2) {
+                taskSwitcher.show();
+            } else {
+                taskSwitcher.hide();
+            }
+        }
+
         Rectangle {
             anchors.fill: parent
             color: root.backgroundColor
@@ -78,3 +106,4 @@ PlasmaCore.ColorScope {
             }
         }
     }
+}