UI: Add helper to delete layout and layout contents

obs/qt-wrappers.cpp

@@ -18,6 +18,7 @@
 #include "qt-wrappers.hpp"
 #include <graphics/graphics.h>
 #include <QWidget>
+#include <QLayout>
 #include <QMessageBox>
 #include <QDataStream>
 
@@ -133,3 +134,25 @@ QDataStream &operator>>(QDataStream &in, OBSSceneItem &si)
 
 	return in;
 }
+
+void DeleteLayout(QLayout *layout)
+{
+	if (!layout)
+		return;
+
+	for (;;) {
+		QLayoutItem *item = layout->takeAt(0);
+		if (!item)
+			break;
+
+		QLayout *subLayout = item->layout();
+		if (subLayout) {
+			DeleteLayout(subLayout);
+		} else {
+			delete item->widget();
+			delete item;
+		}
+	}
+
+	delete layout;
+}

obs/qt-wrappers.hpp

@@ -28,6 +28,7 @@
 
 class QDataStream;
 class QWidget;
+class QLayout;
 struct gs_window;
 
 void OBSErrorBox(QWidget *parent, const char *msg, ...);
@@ -60,3 +61,5 @@ public:
 		widget->blockSignals(blocked);
 	}
 };
+
+void DeleteLayout(QLayout *layout);