Show an appropriate message if Z-Wave is not available on the system

libnymea-app/zwave/zwavemanager.cpp

@@ -50,6 +50,11 @@ bool ZWaveManager::fetchingData() const
     return m_fetchingData;
 }
 
+bool ZWaveManager::zwaveAvailable() const
+{
+    return m_zwaveAvailable;
+}
+
 SerialPorts *ZWaveManager::serialPorts() const
 {
     return m_serialPorts;
@@ -103,6 +108,9 @@ int ZWaveManager::removeFailedNode(const QUuid &networkUuid, int nodeId)
 
 void ZWaveManager::init()
 {
+    m_zwaveAvailable = false;
+    emit zwaveAvailableChanged();
+
     m_fetchingData = true;
     emit fetchingDataChanged();
 
@@ -111,9 +119,16 @@ void ZWaveManager::init()
 
     m_engine->jsonRpcClient()->registerNotificationHandler(this, "ZWave", "notificationReceived");
 
+    m_engine->jsonRpcClient()->sendCommand("ZWave.IsZWaveAvailable", this, "isZWaveAvailableResponse");
     m_engine->jsonRpcClient()->sendCommand("ZWave.GetSerialPorts", this, "getSerialPortsResponse");
-    m_engine->jsonRpcClient()->sendCommand("ZWave.GetNetworks", this, "getNetworksResponse");
+    m_engine->jsonRpcClient()->sendCommand("ZWave.GetNetworks", this, "getNetworksResponse");    
+}
 
+void ZWaveManager::isZWaveAvailableResponse(int commandId, const QVariantMap &params)
+{
+    Q_UNUSED(commandId)
+    m_zwaveAvailable = params.value("available").toBool();
+    emit zwaveAvailableChanged();
 }
 
 void ZWaveManager::getSerialPortsResponse(int commandId, const QVariantMap &params)

libnymea-app/zwave/zwavemanager.h

@@ -46,6 +46,7 @@ class ZWaveManager : public QObject
     Q_OBJECT
     Q_PROPERTY(Engine* engine READ engine WRITE setEngine NOTIFY engineChanged)
     Q_PROPERTY(bool fetchingData READ fetchingData NOTIFY fetchingDataChanged)
+    Q_PROPERTY(bool zwaveAvailable READ zwaveAvailable NOTIFY zwaveAvailableChanged)
 
     Q_PROPERTY(SerialPorts *serialPorts READ serialPorts CONSTANT)
     Q_PROPERTY(ZWaveNetworks *networks READ networks CONSTANT)
@@ -68,6 +69,7 @@ public:
     Engine *engine() const;
 
     bool fetchingData() const;
+    bool zwaveAvailable() const;
 
     SerialPorts *serialPorts() const;
     ZWaveNetworks *networks() const;
@@ -84,6 +86,7 @@ public:
 signals:
     void engineChanged();
     void fetchingDataChanged();
+    void zwaveAvailableChanged();
     void addNetworkReply(int commandId, ZWaveManager::ZWaveError error, const QUuid &networkUuid);
     void removeNetworkReply(int commandId, ZWaveManager::ZWaveError error);
     void cancelPendingOperationReply(int commandId, ZWaveManager::ZWaveError error);
@@ -96,6 +99,7 @@ signals:
 private:
     void init();
 
+    Q_INVOKABLE void isZWaveAvailableResponse(int commandId, const QVariantMap &params);
     Q_INVOKABLE void getSerialPortsResponse(int commandId, const QVariantMap &params);
     Q_INVOKABLE void getNetworksResponse(int commandId, const QVariantMap &params);
     Q_INVOKABLE void getNodesResponse(int commandId, const QVariantMap &params);
@@ -115,6 +119,7 @@ private:
 private:
     Engine* m_engine = nullptr;
     bool m_fetchingData = false;
+    bool m_zwaveAvailable = false;
     SerialPorts *m_serialPorts = nullptr;
     ZWaveNetworks *m_networks = nullptr;
 

nymea-app/ui/components/SettingsPageBase.qml

@@ -48,7 +48,7 @@ Page {
 
     Flickable {
         anchors.fill: parent
-        contentHeight: contentColumn.height + app.margins
+        contentHeight: contentColumn.height + Style.margins
         interactive: contentHeight > height
         clip: true
 

nymea-app/ui/system/zwave/ZWaveSettingsPage.qml

@@ -64,8 +64,8 @@ SettingsPageBase {
 
     Item {
         Layout.fillWidth: true
-        Layout.preferredHeight: root.height
-        visible: zwaveManager.fetchingData || zwaveManager.networks.count == 0
+        Layout.preferredHeight: root.height - root.header.height - Style.margins
+        visible: !zwaveManager.fetchingData || !zwaveManager.zwaveAvailable || zwaveManager.networks.count == 0
 
         BusyIndicator {
             anchors.centerIn: parent
@@ -74,12 +74,15 @@ SettingsPageBase {
         }
 
         EmptyViewPlaceholder {
-            visible: !zwaveManager.fetchingData && zwaveManager.networks.count == 0
+            visible: !zwaveManager.fetchingData
             width: parent.width - app.margins * 2
             anchors.centerIn: parent
             title: qsTr("Z-Wave")
-            text: qsTr("There are no Z-Wave networks set up yet. In order to use Z-Wave, create a Z-Wave network.")
+            text: zwaveManager.zwaveAvailable
+                  ? qsTr("There are no Z-Wave networks set up yet. In order to use Z-Wave, create a Z-Wave network.")
+                  : qsTr("Z-Wave is not available on this system as no Z-Wave backend is installed.")
             imageSource: "/ui/images/z-wave.svg"
+            buttonVisible: zwaveManager.zwaveAvailable
             buttonText: qsTr("Add network")
             onButtonClicked: {
                 addNetwork()
@@ -90,6 +93,7 @@ SettingsPageBase {
 
     ColumnLayout {
         Layout.margins: app.margins / 2
+        visible: !zwaveManager.fetchingData && zwaveManager.zwaveAvailable && zwaveManager.networks.count > 0
         Repeater {
             model: zwaveManager.networks
             delegate: BigTile {