qt: Use human-readable strings in preference to hard-coded integers

This is recommended by Qt docs.
See: https://doc.qt.io/qt-5/qkeysequence.html#details

Also this change avoids -Wdeprecated-enum-enum-conversion warnings.

src/qt/bitcoingui.cpp

@@ -46,6 +46,7 @@
 #include <QCursor>
 #include <QDateTime>
 #include <QDragEnterEvent>
+#include <QKeySequence>
 #include <QListWidget>
 #include <QMenu>
 #include <QMenuBar>
@@ -251,28 +252,28 @@ void BitcoinGUI::createActions()
     overviewAction->setStatusTip(tr("Show general overview of wallet"));
     overviewAction->setToolTip(overviewAction->statusTip());
     overviewAction->setCheckable(true);
-    overviewAction->setShortcut(QKeySequence(Qt::ALT + Qt::Key_1));
+    overviewAction->setShortcut(QKeySequence(QStringLiteral("Alt+1")));
     tabGroup->addAction(overviewAction);
 
     sendCoinsAction = new QAction(platformStyle->SingleColorIcon(":/icons/send"), tr("&Send"), this);
     sendCoinsAction->setStatusTip(tr("Send coins to a Bitcoin address"));
     sendCoinsAction->setToolTip(sendCoinsAction->statusTip());
     sendCoinsAction->setCheckable(true);
-    sendCoinsAction->setShortcut(QKeySequence(Qt::ALT + Qt::Key_2));
+    sendCoinsAction->setShortcut(QKeySequence(QStringLiteral("Alt+2")));
     tabGroup->addAction(sendCoinsAction);
 
     receiveCoinsAction = new QAction(platformStyle->SingleColorIcon(":/icons/receiving_addresses"), tr("&Receive"), this);
     receiveCoinsAction->setStatusTip(tr("Request payments (generates QR codes and bitcoin: URIs)"));
     receiveCoinsAction->setToolTip(receiveCoinsAction->statusTip());
     receiveCoinsAction->setCheckable(true);
-    receiveCoinsAction->setShortcut(QKeySequence(Qt::ALT + Qt::Key_3));
+    receiveCoinsAction->setShortcut(QKeySequence(QStringLiteral("Alt+3")));
     tabGroup->addAction(receiveCoinsAction);
 
     historyAction = new QAction(platformStyle->SingleColorIcon(":/icons/history"), tr("&Transactions"), this);
     historyAction->setStatusTip(tr("Browse transaction history"));
     historyAction->setToolTip(historyAction->statusTip());
     historyAction->setCheckable(true);
-    historyAction->setShortcut(QKeySequence(Qt::ALT + Qt::Key_4));
+    historyAction->setShortcut(QKeySequence(QStringLiteral("Alt+4")));
     tabGroup->addAction(historyAction);
 
 #ifdef ENABLE_WALLET
@@ -290,7 +291,7 @@ void BitcoinGUI::createActions()
 
     quitAction = new QAction(tr("E&xit"), this);
     quitAction->setStatusTip(tr("Quit application"));
-    quitAction->setShortcut(QKeySequence(Qt::CTRL + Qt::Key_Q));
+    quitAction->setShortcut(QKeySequence(tr("Ctrl+Q")));
     quitAction->setMenuRole(QAction::QuitRole);
     aboutAction = new QAction(tr("&About %1").arg(PACKAGE_NAME), this);
     aboutAction->setStatusTip(tr("Show information about %1").arg(PACKAGE_NAME));
@@ -472,7 +473,7 @@ void BitcoinGUI::createMenuBar()
     QMenu* window_menu = appMenuBar->addMenu(tr("&Window"));
 
     QAction* minimize_action = window_menu->addAction(tr("&Minimize"));
-    minimize_action->setShortcut(QKeySequence(Qt::CTRL + Qt::Key_M));
+    minimize_action->setShortcut(QKeySequence(tr("Ctrl+M")));
     connect(minimize_action, &QAction::triggered, [] {
         QApplication::activeWindow()->showMinimized();
     });

src/qt/guiutil.cpp

@@ -47,6 +47,7 @@
 #include <QGuiApplication>
 #include <QJsonObject>
 #include <QKeyEvent>
+#include <QKeySequence>
 #include <QLatin1String>
 #include <QLineEdit>
 #include <QList>
@@ -414,7 +415,7 @@ void bringToFront(QWidget* w)
 
 void handleCloseWindowShortcut(QWidget* w)
 {
-    QObject::connect(new QShortcut(QKeySequence(Qt::CTRL + Qt::Key_W), w), &QShortcut::activated, w, &QWidget::close);
+    QObject::connect(new QShortcut(QKeySequence(QObject::tr("Ctrl+W")), w), &QShortcut::activated, w, &QWidget::close);
 }
 
 void openDebugLogfile()

src/qt/rpcconsole.cpp

@@ -40,6 +40,7 @@
 #include <QDateTime>
 #include <QFont>
 #include <QKeyEvent>
+#include <QKeySequence>
 #include <QLatin1String>
 #include <QLocale>
 #include <QMenu>
@@ -1353,10 +1354,10 @@ QString RPCConsole::tabTitle(TabTypes tab_type) const
 QKeySequence RPCConsole::tabShortcut(TabTypes tab_type) const
 {
     switch (tab_type) {
-    case TabTypes::INFO: return QKeySequence(Qt::CTRL + Qt::Key_I);
+    case TabTypes::INFO: return QKeySequence(tr("Ctrl+I"));
-    case TabTypes::CONSOLE: return QKeySequence(Qt::CTRL + Qt::Key_T);
+    case TabTypes::CONSOLE: return QKeySequence(tr("Ctrl+T"));
-    case TabTypes::GRAPH: return QKeySequence(Qt::CTRL + Qt::Key_N);
+    case TabTypes::GRAPH: return QKeySequence(tr("Ctrl+N"));
-    case TabTypes::PEERS: return QKeySequence(Qt::CTRL + Qt::Key_P);
+    case TabTypes::PEERS: return QKeySequence(tr("Ctrl+P"));
     } // no default case, so the compiler can warn about missing cases
 
     assert(false);