FEAT(client): Implement tray icon highlighting

Previously, only "window highlighting" was supported
by Mumble. However, when Mumble was minimized to tray,
there was no way to observe that highlighting.

As requested in mumble-voip#4584, this commit introduces highlighting
to the tray icon. When a highlight message is received, the
tray icon will flash the "information icon" every two seconds
until the MainWindow of Mumble receives focus again.

To enable this for a specific message type, the user needs to
check the "highlight" box in the "Messages" configuration dialog.

Fixes mumble-voip#4584

src/mumble/Log.cpp

@@ -22,6 +22,8 @@
 #include "VolumeAdjustment.h"
 #include "Global.h"
 
+#include "widgets/TrayIcon.h"
+
 #include <QSignalBlocker>
 #include <QtCore/QMutexLocker>
 #include <QtGui/QImageWriter>
@@ -804,6 +806,7 @@ void Log::log(MsgType mt, const QString &console, const QString &terse, bool own
 			// Message notification with window highlight
 			if (flags & Settings::LogHighlight) {
 				QApplication::alert(Global::get().mw);
+				Global::get().trayIcon->on_highlight();
 			}
 
 			// Message notification with balloon tooltips

src/mumble/MainWindow.cpp

@@ -112,6 +112,7 @@ MainWindow::MainWindow(QWidget *p)
 	SvgIcon::addSvgPixmapsToIcon(qiTalkingOn, QLatin1String("skin:talking_on.svg"));
 	SvgIcon::addSvgPixmapsToIcon(qiTalkingShout, QLatin1String("skin:talking_alt.svg"));
 	SvgIcon::addSvgPixmapsToIcon(qiTalkingWhisper, QLatin1String("skin:talking_whisper.svg"));
+	SvgIcon::addSvgPixmapsToIcon(iconInformation, QLatin1String("skin:Information_icon.svg"));
 
 #ifdef Q_OS_MAC
 	if (QFile::exists(QLatin1String("skin:mumble.icns")))
@@ -721,6 +722,14 @@ void MainWindow::changeEvent(QEvent *e) {
 		}
 	}
 
+	// Unhighlight the tray icon when receiving focus
+	if (e->type() == QEvent::ActivationChange) {
+		if (isActiveWindow() && Global::get().trayIcon != nullptr) {
+			emit Global::get().trayIcon->on_unhighlight();
+		}
+		return;
+	}
+
 	QWidget::changeEvent(e);
 }
 

src/mumble/MainWindow.h

@@ -80,6 +80,7 @@ class MainWindow : public QMainWindow, public Ui::MainWindow {
 	QIcon qiIcon, qiIconMutePushToMute, qiIconMuteSelf, qiIconMuteServer, qiIconDeafSelf, qiIconDeafServer,
 		qiIconMuteSuppressed;
 	QIcon qiTalkingOn, qiTalkingWhisper, qiTalkingShout, qiTalkingOff;
+	QIcon iconInformation;
 	std::unordered_map< unsigned int, qt_unique_ptr< UserLocalNicknameDialog > > qmUserNicknameTracker;
 
 	/// "Action" for when there are no actions available

src/mumble/widgets/TrayIcon.cpp

@@ -12,10 +12,16 @@
 #include <QApplication>
 #include <QDebug>
 
-TrayIcon::TrayIcon() : QSystemTrayIcon(Global::get().mw), m_statusIcon(nullptr) {
-	setIcon(Global::get().mw->qiIcon);
+TrayIcon::TrayIcon()
+	: QSystemTrayIcon(Global::get().mw), m_statusIcon(&Global::get().mw->qiIcon), m_currentIcon(nullptr),
+	  m_iconLock(QReadWriteLock::NonRecursive) {
+	applyIcon(m_statusIcon);
 	setToolTip("Mumble");
 
+	m_highlightTimer = new QTimer(this);
+	m_highlightTimer->setSingleShot(true);
+	QObject::connect(m_highlightTimer, &QTimer::timeout, this, &TrayIcon::on_timer_triggered);
+
 	QObject::connect(this, &QSystemTrayIcon::activated, this, &TrayIcon::on_icon_clicked);
 
 	// messageClicked is buggy in Qt on some platforms and we can not do anything about this (QTBUG-87329)
@@ -76,9 +82,16 @@ void TrayIcon::updateIcon() {
 		newIcon = &Global::get().mw->qiIcon;
 	}
 
-	if (newIcon != m_statusIcon) {
+	m_iconLock.lockForRead();
+	bool isStatusIcon = newIcon == m_statusIcon;
+	m_iconLock.unlock();
+
+	if (!isStatusIcon) {
+		m_iconLock.lockForWrite();
 		m_statusIcon = newIcon;
-		setIcon(*m_statusIcon);
+		m_iconLock.unlock();
+
+		applyIcon(m_statusIcon);
 	}
 }
 
@@ -125,6 +138,13 @@ void TrayIcon::updateContextMenu() {
 	m_contextMenu->addAction(Global::get().mw->qaQuit);
 }
 
+void TrayIcon::applyIcon(QIcon *icon) {
+	QWriteLocker locker(&m_iconLock);
+
+	setIcon(*icon);
+	m_currentIcon = icon;
+}
+
 void TrayIcon::toggleShowHide() {
 	if (Global::get().mw->isVisible() && !Global::get().mw->isMinimized()) {
 		on_hideAction_triggered();
@@ -168,3 +188,32 @@ void TrayIcon::on_hideAction_triggered() {
 
 	updateContextMenu();
 }
+
+void TrayIcon::on_highlight() {
+	qDebug() << "Tray: Highlight notification received!";
+	on_timer_triggered();
+}
+
+void TrayIcon::on_unhighlight() {
+	if (m_highlightTimer == nullptr || !m_highlightTimer->isActive()) {
+		return;
+	}
+
+	qDebug() << "Tray: Unhighlight...";
+	m_highlightTimer->stop();
+	applyIcon(m_statusIcon);
+}
+
+void TrayIcon::on_timer_triggered() {
+	m_iconLock.lockForRead();
+	bool isStatusIcon = m_currentIcon == m_statusIcon;
+	m_iconLock.unlock();
+
+	if (isStatusIcon) {
+		applyIcon(&Global::get().mw->iconInformation);
+		m_highlightTimer->start(500);
+	} else {
+		applyIcon(m_statusIcon);
+		m_highlightTimer->start(2000);
+	}
+}

src/mumble/widgets/TrayIcon.h

@@ -8,6 +8,8 @@
 
 #include "../../QtUtils.h"
 #include <QAction>
+#include <QReadWriteLock>
+#include <QTimer>
 #include <QtWidgets/QMenu>
 #include <QtWidgets/QSystemTrayIcon>
 
@@ -23,17 +25,24 @@ class TrayIcon : public QSystemTrayIcon {
 public slots:
 	void on_showAction_triggered();
 	void on_hideAction_triggered();
+	void on_highlight();
+	void on_unhighlight();
 
 private:
 	QIcon *m_statusIcon;
+	QIcon *m_currentIcon;
 	QMenu *m_contextMenu;
 	QAction *m_showAction;
 	QAction *m_hideAction;
+	QTimer *m_highlightTimer;
+	QReadWriteLock m_iconLock;
 
 	void updateContextMenu();
+	void applyIcon(QIcon *icon);
 
 private slots:
 	void on_icon_clicked(QSystemTrayIcon::ActivationReason reason);
+	void on_timer_triggered();
 };
 
 #endif // MUMBLE_MUMBLE_WIDGETS_TRAYICCON_H_