From 33ee00f3f66e1036a14495c2e17b5c0ace41576d Mon Sep 17 00:00:00 2001
From: Nyall Dawson <nyall.dawson@gmail.com>
Date: Tue, 16 Jul 2019 09:11:22 +1000
Subject: [PATCH] Ensure layer tree indicator icons are repainted on changes

---
 .../layertree/qgslayertreeviewindicator.sip.in            | 7 +++++++
 src/gui/layertree/qgslayertreeview.cpp                    | 5 +++++
 src/gui/layertree/qgslayertreeviewindicator.h             | 8 +++++++-
 3 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/python/gui/auto_generated/layertree/qgslayertreeviewindicator.sip.in b/python/gui/auto_generated/layertree/qgslayertreeviewindicator.sip.in
index cf2488871a8..ffb26965a4b 100644
--- a/python/gui/auto_generated/layertree/qgslayertreeviewindicator.sip.in
+++ b/python/gui/auto_generated/layertree/qgslayertreeviewindicator.sip.in
@@ -52,6 +52,13 @@ Sets tool tip text
     void clicked( const QModelIndex &index );
 %Docstring
 Emitted when user clicks on the indicator
+%End
+
+    void changed();
+%Docstring
+Emitted when the indicator changes state (e.g. icon).
+
+.. versionadded:: 3.10
 %End
 
 };
diff --git a/src/gui/layertree/qgslayertreeview.cpp b/src/gui/layertree/qgslayertreeview.cpp
index dd7b5942975..899aa924818 100644
--- a/src/gui/layertree/qgslayertreeview.cpp
+++ b/src/gui/layertree/qgslayertreeview.cpp
@@ -398,12 +398,17 @@ QList<QgsMapLayer *> QgsLayerTreeView::selectedLayersRecursive() const
 void QgsLayerTreeView::addIndicator( QgsLayerTreeNode *node, QgsLayerTreeViewIndicator *indicator )
 {
   if ( !mIndicators[node].contains( indicator ) )
+  {
     mIndicators[node].append( indicator );
+    connect( indicator, &QgsLayerTreeViewIndicator::changed, this, [ = ] { update(); } );
+    update();
+  }
 }
 
 void QgsLayerTreeView::removeIndicator( QgsLayerTreeNode *node, QgsLayerTreeViewIndicator *indicator )
 {
   mIndicators[node].removeOne( indicator );
+  update();
 }
 
 QList<QgsLayerTreeViewIndicator *> QgsLayerTreeView::indicators( QgsLayerTreeNode *node ) const
diff --git a/src/gui/layertree/qgslayertreeviewindicator.h b/src/gui/layertree/qgslayertreeviewindicator.h
index 4c917cdeb93..8695c7337cb 100644
--- a/src/gui/layertree/qgslayertreeviewindicator.h
+++ b/src/gui/layertree/qgslayertreeviewindicator.h
@@ -42,7 +42,7 @@ class GUI_EXPORT QgsLayerTreeViewIndicator : public QObject
     //! Indicator icon that will be displayed in the layer tree view
     QIcon icon() const { return mIcon; }
     //! Sets indicator icon that will be displayed in the layer tree view
-    void setIcon( const QIcon &icon ) { mIcon = icon; }
+    void setIcon( const QIcon &icon ) { mIcon = icon; emit changed(); }
 
     //! Returns tool tip text that will be shown when user hovers mouse over the indicator
     QString toolTip() const { return mToolTip; }
@@ -53,6 +53,12 @@ class GUI_EXPORT QgsLayerTreeViewIndicator : public QObject
     //! Emitted when user clicks on the indicator
     void clicked( const QModelIndex &index );
 
+    /**
+     * Emitted when the indicator changes state (e.g. icon).
+     * \since QGIS 3.10
+     */
+    void changed();
+
   private:
     QIcon mIcon;
     QString mToolTip;