Add an indicator in the title bar if Streamer Mode is active (#4410)

src/widgets/Window.cpp

@@ -9,6 +9,7 @@
 #include "controllers/hotkeys/HotkeyController.hpp"
 #include "providers/twitch/TwitchAccount.hpp"
 #include "providers/twitch/TwitchIrcServer.hpp"
+#include "singletons/Resources.hpp"
 #include "singletons/Settings.hpp"
 #include "singletons/Theme.hpp"
 #include "singletons/Updates.hpp"
@@ -186,6 +187,51 @@ void Window::addCustomTitlebarButtons()
             this->userLabel_->rect().bottomLeft()));
     });
     this->userLabel_->setMinimumWidth(20 * scale());
+
+    // streamer mode
+    this->streamerModeTitlebarIcon_ =
+        this->addTitleBarButton(TitleBarButtonStyle::StreamerMode, [this] {
+            getApp()->windows->showSettingsDialog(
+                this, SettingsDialogPreference::StreamerMode);
+        });
+    this->signalHolder_.managedConnect(getApp()->streamerModeChanged, [this]() {
+        this->updateStreamerModeIcon();
+    });
+}
+
+void Window::updateStreamerModeIcon()
+{
+    // A duplicate of this code is in SplitNotebook class (in Notebook.{c,h}pp)
+    // That one is the one near splits (on linux and mac or non-main windows on Windows)
+    // This copy handles the TitleBar icon in Window (main window on Windows)
+    if (this->streamerModeTitlebarIcon_ == nullptr)
+    {
+        return;
+    }
+#ifdef Q_OS_WIN
+    assert(this->getType() == WindowType::Main);
+    if (getTheme()->isLightTheme())
+    {
+        this->streamerModeTitlebarIcon_->setPixmap(
+            getResources().buttons.streamerModeEnabledLight);
+    }
+    else
+    {
+        this->streamerModeTitlebarIcon_->setPixmap(
+            getResources().buttons.streamerModeEnabledDark);
+    }
+    this->streamerModeTitlebarIcon_->setVisible(isInStreamerMode());
+#else
+    // clang-format off
+    assert(false && "Streamer mode TitleBar icon should not exist on non-Windows OSes");
+    // clang-format on
+#endif
+}
+
+void Window::themeChangedEvent()
+{
+    this->updateStreamerModeIcon();
+    BaseWindow::themeChangedEvent();
 }
 
 void Window::addDebugStuff(HotkeyController::HotkeyMap &actions)