Add new global shortcut system backend for X11 and Windows

- Remove qxt
- Also create an option for enabled/disabling shortcuts through X11.

src/globalshortcuts/globalshortcutbackend-system.cpp

@@ -0,0 +1,70 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry 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.
+ *
+ * Strawberry 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 Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include "globalshortcutbackend-system.h"
+
+#include "core/logging.h"
+
+#include <QtGlobal>
+#include <QObject>
+#include <QAction>
+#include <QtAlgorithms>
+
+#include "globalshortcuts.h"
+#include "globalshortcutbackend.h"
+#include "globalshortcut.h"
+
+GlobalShortcutBackendSystem::GlobalShortcutBackendSystem(GlobalShortcuts *parent) : GlobalShortcutBackend(parent),
+  gshortcut_init_(new GlobalShortcut(this)) {}
+
+GlobalShortcutBackendSystem::~GlobalShortcutBackendSystem(){}
+
+bool GlobalShortcutBackendSystem::DoRegister() {
+
+  qLog(Debug) << "Registering";
+
+  for (const GlobalShortcuts::Shortcut &shortcut : manager_->shortcuts().values()) {
+    AddShortcut(shortcut.action);
+  }
+
+  return true;
+
+}
+
+bool GlobalShortcutBackendSystem::AddShortcut(QAction *action) {
+
+  if (action->shortcut().isEmpty()) return false;
+
+  GlobalShortcut *shortcut = new GlobalShortcut(action->shortcut(), this, this);
+  connect(shortcut, SIGNAL(activated()), action, SLOT(trigger()));
+  shortcuts_ << shortcut;
+  return true;
+
+}
+
+void GlobalShortcutBackendSystem::DoUnregister() {
+
+  qLog(Debug) << "Unregistering";
+  qDeleteAll(shortcuts_);
+  shortcuts_.clear();
+
+}
+