Other: fix bug in login screen <-> main window transition. [skip ci]

Other: fixed bug with split mode toggle. [skip ci]

Other: fix QML warnings. [skip ci]

Other: fix showMainWindow gRPC event binding. [skip ci].

QML Fixes [skip ci]

Other: wait for EventStreamReader thread to finish on exit.

Other: made BridgeMonitor generic, as ProcessMonitor. [skip ci]

internal/frontend/bridge-gui/bridgepp/bridgepp/ProcessMonitor.h

@@ -0,0 +1,67 @@
+// Copyright (c) 2022 Proton AG
+//
+// This file is part of Proton Mail Bridge.
+//
+// Proton Mail Bridge 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 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail Bridge 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 Proton Mail Bridge. If not, see <https://www.gnu.org/licenses/>.
+
+
+#ifndef BRIDGE_PP_PROCESS_MONITOR_H
+#define BRIDGE_PP_PROCESS_MONITOR_H
+
+
+#include "Worker/Worker.h"
+
+
+namespace bridgepp
+{
+
+
+//**********************************************************************************************************************
+/// \brief Process launcher and monitor class.
+//**********************************************************************************************************************
+class ProcessMonitor : public Worker
+{
+Q_OBJECT
+public: // static member functions
+    struct MonitorStatus
+    {
+        bool running = false;
+        int returnCode = 0;
+        qint64 pid = 0;
+    };
+
+public: // member functions.
+    ProcessMonitor(QString const &exePath, QStringList const &args, QObject *parent); ///< Default constructor.
+    ProcessMonitor(ProcessMonitor const &) = delete; ///< Disabled copy-constructor.
+    ProcessMonitor(ProcessMonitor &&) = delete; ///< Disabled assignment copy-constructor.
+    ~ProcessMonitor() override = default; ///< Destructor.
+    ProcessMonitor &operator=(ProcessMonitor const &) = delete; ///< Disabled assignment operator.
+    ProcessMonitor &operator=(ProcessMonitor &&) = delete; ///< Disabled move assignment operator.
+    void run() override; ///< Run the worker.
+    MonitorStatus const &getStatus();
+
+signals:
+    void processExited(int code); ///< Slot for the exiting of the process.
+
+private: // data members
+    QString const exePath_; ///< The path to the executable.
+    QStringList args_; ///< arguments to be passed to the brigde.
+    MonitorStatus status_; ///< Status of the monitoring.
+};
+
+
+}
+
+
+#endif //BRIDGE_PP_PROCESS_MONITOR_H