gui: Replace "Hide tray icon" option with positive "Show tray icon" one

This change makes easier both (1) using this option, and (2) reasoning
about the code.

src/qt/bitcoingui.cpp

@@ -615,10 +615,10 @@ void BitcoinGUI::setClientModel(ClientModel *_clientModel, interfaces::BlockAndH
         OptionsModel* optionsModel = _clientModel->getOptionsModel();
         if (optionsModel && trayIcon) {
             // be aware of the tray icon disable state change reported by the OptionsModel object.
-            connect(optionsModel, &OptionsModel::hideTrayIconChanged, this, &BitcoinGUI::setTrayIconVisible);
+            connect(optionsModel, &OptionsModel::showTrayIconChanged, this, &BitcoinGUI::setTrayIconVisible);
 
             // initialize the disable state of the tray icon with the current value in the model.
-            setTrayIconVisible(optionsModel->getHideTrayIcon());
+            setTrayIconVisible(optionsModel->getShowTrayIcon());
         }
     } else {
         // Disable possibility to show main window via action
@@ -1387,11 +1387,10 @@ void BitcoinGUI::showProgress(const QString &title, int nProgress)
     }
 }
 
-void BitcoinGUI::setTrayIconVisible(bool fHideTrayIcon)
+void BitcoinGUI::setTrayIconVisible(bool show_tray_con)
 {
-    if (trayIcon)
-    {
-        trayIcon->setVisible(!fHideTrayIcon);
+    if (trayIcon) {
+        trayIcon->setVisible(show_tray_con);
     }
 }
 

src/qt/bitcoingui.h

@@ -317,7 +317,7 @@ public Q_SLOTS:
     /** Show progress dialog e.g. for verifychain */
     void showProgress(const QString &title, int nProgress);
 
-    /** When hideTrayIcon setting is changed in OptionsModel hide or show the icon accordingly. */
+    /** When showTrayIcon setting is changed in OptionsModel show or hide the icon accordingly. */
     void setTrayIconVisible(bool);
 
     void showModalOverlay();

src/qt/forms/optionsdialog.ui

@@ -568,12 +568,15 @@
       </attribute>
       <layout class="QVBoxLayout" name="verticalLayout_Window">
        <item>
-        <widget class="QCheckBox" name="hideTrayIcon">
+        <widget class="QCheckBox" name="showTrayIcon">
          <property name="toolTip">
-          <string>Hide the icon from the system tray.</string>
+          <string>Show the icon in the system tray.</string>
          </property>
          <property name="text">
-          <string>&amp;Hide tray icon</string>
+          <string>&amp;Show tray icon</string>
+         </property>
+         <property name="checked">
+          <bool>true</bool>
          </property>
         </widget>
        </item>

src/qt/optionsdialog.cpp

@@ -130,8 +130,8 @@ OptionsDialog::OptionsDialog(QWidget *parent, bool enableWallet) :
     connect(ui->proxyPortTor, &QLineEdit::textChanged, this, &OptionsDialog::updateProxyValidationState);
 
     if (!QSystemTrayIcon::isSystemTrayAvailable()) {
-        ui->hideTrayIcon->setChecked(true);
-        ui->hideTrayIcon->setEnabled(false);
+        ui->showTrayIcon->setChecked(false);
+        ui->showTrayIcon->setEnabled(false);
         ui->minimizeToTray->setChecked(false);
         ui->minimizeToTray->setEnabled(false);
     }
@@ -227,7 +227,7 @@ void OptionsDialog::setMapper()
     /* Window */
 #ifndef Q_OS_MAC
     if (QSystemTrayIcon::isSystemTrayAvailable()) {
-        mapper->addMapping(ui->hideTrayIcon, OptionsModel::HideTrayIcon);
+        mapper->addMapping(ui->showTrayIcon, OptionsModel::ShowTrayIcon);
         mapper->addMapping(ui->minimizeToTray, OptionsModel::MinimizeToTray);
     }
     mapper->addMapping(ui->minimizeOnClose, OptionsModel::MinimizeOnClose);
@@ -286,17 +286,14 @@ void OptionsDialog::on_cancelButton_clicked()
     reject();
 }
 
-void OptionsDialog::on_hideTrayIcon_stateChanged(int fState)
+void OptionsDialog::on_showTrayIcon_stateChanged(int state)
 {
-    if(fState)
-    {
+    if (state == Qt::Checked) {
+        ui->minimizeToTray->setEnabled(true);
+    } else {
         ui->minimizeToTray->setChecked(false);
         ui->minimizeToTray->setEnabled(false);
     }
-    else
-    {
-        ui->minimizeToTray->setEnabled(true);
-    }
 }
 
 void OptionsDialog::togglePruneWarning(bool enabled)

src/qt/optionsdialog.h

@@ -57,7 +57,7 @@ private Q_SLOTS:
     void on_okButton_clicked();
     void on_cancelButton_clicked();
 
-    void on_hideTrayIcon_stateChanged(int fState);
+    void on_showTrayIcon_stateChanged(int state);
 
     void togglePruneWarning(bool enabled);
     void showRestartWarning(bool fPersistent = false);

src/qt/optionsmodel.cpp

@@ -54,14 +54,15 @@ void OptionsModel::Init(bool resetSettings)
     // These are Qt-only settings:
 
     // Window
-    if (!settings.contains("fHideTrayIcon"))
+    if (!settings.contains("fHideTrayIcon")) {
         settings.setValue("fHideTrayIcon", false);
-    fHideTrayIcon = settings.value("fHideTrayIcon").toBool();
-    Q_EMIT hideTrayIconChanged(fHideTrayIcon);
+    }
+    m_show_tray_icon = !settings.value("fHideTrayIcon").toBool();
+    Q_EMIT showTrayIconChanged(m_show_tray_icon);
 
     if (!settings.contains("fMinimizeToTray"))
         settings.setValue("fMinimizeToTray", false);
-    fMinimizeToTray = settings.value("fMinimizeToTray").toBool() && !fHideTrayIcon;
+    fMinimizeToTray = settings.value("fMinimizeToTray").toBool() && m_show_tray_icon;
 
     if (!settings.contains("fMinimizeOnClose"))
         settings.setValue("fMinimizeOnClose", false);
@@ -272,8 +273,8 @@ QVariant OptionsModel::data(const QModelIndex & index, int role) const
         {
         case StartAtStartup:
             return GUIUtil::GetStartOnSystemStartup();
-        case HideTrayIcon:
-            return fHideTrayIcon;
+        case ShowTrayIcon:
+            return m_show_tray_icon;
         case MinimizeToTray:
             return fMinimizeToTray;
         case MapPortUPnP:
@@ -342,10 +343,10 @@ bool OptionsModel::setData(const QModelIndex & index, const QVariant & value, in
         case StartAtStartup:
             successful = GUIUtil::SetStartOnSystemStartup(value.toBool());
             break;
-        case HideTrayIcon:
-            fHideTrayIcon = value.toBool();
-            settings.setValue("fHideTrayIcon", fHideTrayIcon);
-    		Q_EMIT hideTrayIconChanged(fHideTrayIcon);
+        case ShowTrayIcon:
+            m_show_tray_icon = value.toBool();
+            settings.setValue("fHideTrayIcon", !m_show_tray_icon);
+            Q_EMIT showTrayIconChanged(m_show_tray_icon);
             break;
         case MinimizeToTray:
             fMinimizeToTray = value.toBool();

src/qt/optionsmodel.h

@@ -45,7 +45,7 @@ public:
 
     enum OptionID {
         StartAtStartup,         // bool
-        HideTrayIcon,           // bool
+        ShowTrayIcon,           // bool
         MinimizeToTray,         // bool
         MapPortUPnP,            // bool
         MinimizeOnClose,        // bool
@@ -78,7 +78,7 @@ public:
     void setDisplayUnit(const QVariant &value);
 
     /* Explicit getters */
-    bool getHideTrayIcon() const { return fHideTrayIcon; }
+    bool getShowTrayIcon() const { return m_show_tray_icon; }
     bool getMinimizeToTray() const { return fMinimizeToTray; }
     bool getMinimizeOnClose() const { return fMinimizeOnClose; }
     int getDisplayUnit() const { return nDisplayUnit; }
@@ -100,7 +100,7 @@ public:
 private:
     interfaces::Node* m_node = nullptr;
     /* Qt-only settings */
-    bool fHideTrayIcon;
+    bool m_show_tray_icon;
     bool fMinimizeToTray;
     bool fMinimizeOnClose;
     QString language;
@@ -118,7 +118,7 @@ private:
 Q_SIGNALS:
     void displayUnitChanged(int unit);
     void coinControlFeaturesChanged(bool);
-    void hideTrayIconChanged(bool);
+    void showTrayIconChanged(bool);
 };
 
 #endif // BITCOIN_QT_OPTIONSMODEL_H