From ada4ed2a986a637ea2007dc8560d7d6da92a2acb Mon Sep 17 00:00:00 2001
From: Oliver Eichler <oliver.eichler@gmx.de>
Date: Fri, 15 Sep 2023 10:43:37 +0200
Subject: [PATCH] [QMS-547] Fixed: QMS freezes on zoom when activating
 multi-layered online maps

---
 changelog.txt                  |  4 +++-
 src/qmapshack/map/CMapTMS.cpp  | 23 ++++++++++++-----------
 src/qmapshack/map/CMapWMTS.cpp | 23 ++++++++++++-----------
 src/qmapshack/map/IMapOnline.h | 15 +++++++--------
 4 files changed, 34 insertions(+), 31 deletions(-)

diff --git a/changelog.txt b/changelog.txt
index 706a8e026..f8ba2f5c6 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -1,5 +1,7 @@
+V1.XX.X
+[QMS-547] Fixed: QMS freezes on zoom when activating multi-layered online maps
 [QMS-622] Update BRouter setup (install from github)
-[QMS-623] remove use of QTimer in brouter startup error detection
+[QMS-623] remove use of QTimer in BRouter startup error detection
 [QMS-630] BRouter on-the-fly routing cannot be canceled
 
 V1.17.0
diff --git a/src/qmapshack/map/CMapTMS.cpp b/src/qmapshack/map/CMapTMS.cpp
index fbefbc470..78046e034 100644
--- a/src/qmapshack/map/CMapTMS.cpp
+++ b/src/qmapshack/map/CMapTMS.cpp
@@ -151,21 +151,22 @@ CMapTMS::CMapTMS(const QString& filename, CMapDraw* parent) : IMapOnline(parent)
 
 void CMapTMS::getLayers(QListWidget& list) /* override */
 {
-  QMutexLocker lock(&mutex);
-
-  list.clear();
-  if (layers.size() < 2) {
+  if (!mutex.tryLock(100)) {
     return;
   }
 
-  int i = 0;
-  for (const layer_t& layer : qAsConst(layers)) {
-    QListWidgetItem* item = new QListWidgetItem(layer.title, &list);
-    item->setCheckState(layer.enabled ? Qt::Checked : Qt::Unchecked);
-    item->setData(Qt::UserRole, i++);
-  }
+  list.clear();
+  if (layers.size() > 1) {
+    int i = 0;
+    for (const layer_t& layer : qAsConst(layers)) {
+      QListWidgetItem* item = new QListWidgetItem(layer.title, &list);
+      item->setCheckState(layer.enabled ? Qt::Checked : Qt::Unchecked);
+      item->setData(Qt::UserRole, i++);
+    }
 
-  connect(&list, &QListWidget::itemChanged, this, &CMapTMS::slotLayersChanged);
+    connect(&list, &QListWidget::itemChanged, this, &CMapTMS::slotLayersChanged);
+  }
+  mutex.unlock();
 }
 
 void CMapTMS::saveConfig(QSettings& cfg) /* override */
diff --git a/src/qmapshack/map/CMapWMTS.cpp b/src/qmapshack/map/CMapWMTS.cpp
index 718c58628..89e973ac4 100644
--- a/src/qmapshack/map/CMapWMTS.cpp
+++ b/src/qmapshack/map/CMapWMTS.cpp
@@ -251,21 +251,22 @@ CMapWMTS::CMapWMTS(const QString& filename, CMapDraw* parent) : IMapOnline(paren
 }
 
 void CMapWMTS::getLayers(QListWidget& list) {
-  QMutexLocker lock(&mutex);
-
-  list.clear();
-  if (layers.size() < 2) {
+  if (!mutex.tryLock(100)) {
     return;
   }
 
-  int i = 0;
-  for (const layer_t& layer : qAsConst(layers)) {
-    QListWidgetItem* item = new QListWidgetItem(layer.title, &list);
-    item->setCheckState(layer.enabled ? Qt::Checked : Qt::Unchecked);
-    item->setData(Qt::UserRole, i++);
-  }
+  list.clear();
+  if (layers.size() > 1) {
+    int i = 0;
+    for (const layer_t& layer : qAsConst(layers)) {
+      QListWidgetItem* item = new QListWidgetItem(layer.title, &list);
+      item->setCheckState(layer.enabled ? Qt::Checked : Qt::Unchecked);
+      item->setData(Qt::UserRole, i++);
+    }
 
-  connect(&list, &QListWidget::itemChanged, this, &CMapWMTS::slotLayersChanged);
+    connect(&list, &QListWidget::itemChanged, this, &CMapWMTS::slotLayersChanged);
+  }
+  mutex.unlock();
 }
 
 void CMapWMTS::saveConfig(QSettings& cfg) /* override */
diff --git a/src/qmapshack/map/IMapOnline.h b/src/qmapshack/map/IMapOnline.h
index dbd36e4e7..c05e94bbc 100644
--- a/src/qmapshack/map/IMapOnline.h
+++ b/src/qmapshack/map/IMapOnline.h
@@ -31,7 +31,14 @@ class QNetworkReply;
 
 class IMapOnline : public IMap {
   Q_OBJECT
+ public:
+  IMapOnline(CMapDraw* parent);
+  virtual ~IMapOnline() {}
+
+ signals:
+  void sigQueueChanged();
 
+ protected:
   struct rawHeaderItem_t {
     QString name;
     QString value;
@@ -39,10 +46,6 @@ class IMapOnline : public IMap {
 
   QList<rawHeaderItem_t> rawHeaderItems;
 
- signals:
-  void sigQueueChanged();
-
- protected:
   /// Mutex to control access to url queue
   QRecursiveMutex mutex;
   /// a queue with all tile urls to request
@@ -68,12 +71,8 @@ class IMapOnline : public IMap {
 
   void configureCache() override;
 
- public:
   void slotQueueChanged();
   void slotRequestFinished(QNetworkReply* reply);
-
-  IMapOnline(CMapDraw* parent);
-  virtual ~IMapOnline() {}
 };
 
 #endif  // IMAPONLINE_H