Introduce QML component to check for plugin availability

Remove those checks from three different places and put them into a reusable
component, which can be used for different plugins.

REVIEW: 127583

plasmoid/package/contents/ui/Battery.qml

@@ -27,9 +27,14 @@ QtObject {
   
     id: root
     
-    property string deviceId: ""
+    property alias deviceId: checker.deviceId
-    property variant device: DeviceDbusInterfaceFactory.create(deviceId)
+    readonly property alias device: checker.device
-    property bool available: false
+    readonly property alias available: checker.available
+
+    readonly property PluginChecker pluginChecker: PluginChecker {
+        id: checker
+        pluginName: "battery"
+    }
 
     property bool charging: false
     property int charge: -1
@@ -48,7 +53,6 @@ QtObject {
         onSuccess: root.charge = result
     }
     
-    // Note: magically called by qml
     onAvailableChanged: {
         if (available) {
             battery = DeviceBatteryDbusInterfaceFactory.create(deviceId)
@@ -62,19 +66,4 @@ QtObject {
             battery = null
         }
     }
-    
-    function pluginsChanged() {
-        var result = DBusResponseWaiter.waitForReply(device.hasPlugin("kdeconnect_battery"))
-      
-        if (result && result != "error") {
-            available = true
-        } else {
-            available = false
-        }      
-    }
-    
-    Component.onCompleted: {
-        device.pluginsChanged.connect(pluginsChanged)
-        device.pluginsChanged()
-    }
 }

plasmoid/package/contents/ui/FindMyPhone.qml

@@ -27,9 +27,14 @@ QtObject {
 
     id: root
 
-    property string deviceId: ""
+    property alias deviceId: checker.deviceId
-    property variant device: DeviceDbusInterfaceFactory.create(deviceId)
+    readonly property alias device: checker.device
-    property bool available: false
+    readonly property alias available: checker.available
+
+    readonly property PluginChecker pluginChecker: PluginChecker {
+        id: checker
+        pluginName: "findmyphone"
+    }
 
     property variant findMyPhone: null
 
@@ -39,12 +44,6 @@ QtObject {
         }
     }
 
-    Component.onCompleted: {
-        device.pluginsChanged.connect(pluginsChanged)
-        pluginsChanged()
-    }
-
-    // Note: magically called by qml
     onAvailableChanged: {
         if (available) {
             findMyPhone = FindMyPhoneDbusInterfaceFactory.create(deviceId)
@@ -52,10 +51,4 @@ QtObject {
             findMyPhone = null
         }
     }
-
-    function pluginsChanged() {
-        var result = DBusResponseWaiter.waitForReply(device.hasPlugin("kdeconnect_findmyphone"))
-        available = (result && result != "error");
-    }
-
 }

plasmoid/package/contents/ui/PluginChecker.qml

@@ -0,0 +1,45 @@
+/**
+ * Copyright 2014 Samoilenko Yuri <kinnalru@gmail.com>
+ * Copyright 2016 David Kahles <david.kahles96@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License or (at your option) version 3 or any later version
+ * accepted by the membership of KDE e.V. (or its successor approved
+ * by the membership of KDE e.V.), which shall act as a proxy
+ * defined in Section 14 of version 3 of the license.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import QtQml 2.2
+import org.kde.kdeconnect 1.0
+
+QtObject {
+
+    id: root
+
+    property string deviceId: ""
+    property string pluginName: ""
+    readonly property variant device: DeviceDbusInterfaceFactory.create(deviceId)
+    property bool available: false
+
+    property Connections connection: Connections {
+        target: device
+        onPluginsChanged: pluginsChanged()
+    }
+
+    Component.onCompleted: pluginsChanged()
+
+    function pluginsChanged() {
+        var result = DBusResponseWaiter.waitForReply(device.hasPlugin("kdeconnect_" + pluginName))
+        available = (result && result != "error");
+    }
+}

plasmoid/package/contents/ui/Sftp.qml

@@ -27,9 +27,14 @@ QtObject {
 
     id: root
 
-    property string deviceId: ""
+    property alias deviceId: checker.deviceId
-    property variant device: DeviceDbusInterfaceFactory.create(deviceId)
+    readonly property alias device: checker.device
-    property bool available: false
+    readonly property alias available: checker.available
+
+    readonly property PluginChecker pluginChecker: PluginChecker {
+        id: checker
+        pluginName: "sftp"
+    }
 
     property variant sftp: null
 
@@ -38,12 +43,6 @@ QtObject {
             sftp.startBrowsing();
     }
 
-    Component.onCompleted: {
-        device.pluginsChanged.connect(pluginsChanged)
-        pluginsChanged()
-    }
-
-    // Note: magically called by qml
     onAvailableChanged: {
         if (available) {
             sftp = SftpDbusInterfaceFactory.create(deviceId)
@@ -51,10 +50,4 @@ QtObject {
             sftp = null
         }
     }
-
-    function pluginsChanged() {
-        var result = DBusResponseWaiter.waitForReply(device.hasPlugin("kdeconnect_sftp"))
-        available = (result && result != "error");
-    }
-
 }