From d268b919071863d2a5287b64304e77ade07d55d3 Mon Sep 17 00:00:00 2001
From: Shawn Rutledge <shawn.rutledge@qt.io>
Date: Fri, 29 May 2020 11:25:14 +0200
Subject: [PATCH] Add QT_QPA_SYSTEM_ICON_THEME to override icon theme name

On a plain X11 desktop, it otherwise ends up empty.

Pick-to: 5.15
Task-number: QTBUG-25351
Task-number: QTBUG-25718
Task-number: QTBUG-74252
Change-Id: I50a522a3e1761e422d5949d5338869ceb9e5e89d
Reviewed-by: Albert Astals Cid <albert.astals.cid@kdab.com>
---
 src/gui/image/qiconloader.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/gui/image/qiconloader.cpp b/src/gui/image/qiconloader.cpp
index 3fa3bb9c598..ac7a6864f82 100644
--- a/src/gui/image/qiconloader.cpp
+++ b/src/gui/image/qiconloader.cpp
@@ -79,6 +79,9 @@ QIconLoader::QIconLoader() :
 
 static inline QString systemThemeName()
 {
+    const auto override = qgetenv("QT_QPA_SYSTEM_ICON_THEME");
+    if (!override.isEmpty())
+        return QString::fromLocal8Bit(override);
     if (const QPlatformTheme *theme = QGuiApplicationPrivate::platformTheme()) {
         const QVariant themeHint = theme->themeHint(QPlatformTheme::SystemIconThemeName);
         if (themeHint.isValid())