From d421b857e535aa5de7d00de084978f2e6947fbb3 Mon Sep 17 00:00:00 2001
From: Denis Rouzaud <denis.rouzaud@gmail.com>
Date: Tue, 6 Feb 2018 14:57:04 -0400
Subject: [PATCH] QgsReadWriteContext can store message

app will show them in message bar when loading layers
---
 python/core/qgsproject.sip.in          |  4 +++-
 python/core/qgsreadwritecontext.sip.in | 10 ++++++++++
 src/app/qgisapp.cpp                    | 10 ++++++++++
 src/app/qgisapp.h                      |  2 ++
 src/core/qgsproject.cpp                |  5 +++++
 src/core/qgsproject.h                  |  4 +++-
 src/core/qgsreadwritecontext.h         |  8 ++++++++
 7 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/python/core/qgsproject.sip.in b/python/core/qgsproject.sip.in
index c96e7ab20e7..3b2cd4609fb 100644
--- a/python/core/qgsproject.sip.in
+++ b/python/core/qgsproject.sip.in
@@ -910,7 +910,9 @@ Emitted when a layer from a projects was read.
 :param n: number of layers
 %End
 
-    void loadingLayer( const QString & );
+    void loadingLayer( const QString &layerName );
+
+    void loadingLayerMessages( const QString &layerName, const QList<QPair<Qgis::MessageLevel, QString>> &messages );
 
     void nonIdentifiableLayersChanged( QStringList nonIdentifiableLayers );
 %Docstring
diff --git a/python/core/qgsreadwritecontext.sip.in b/python/core/qgsreadwritecontext.sip.in
index a92aed4bce2..427a18518af 100644
--- a/python/core/qgsreadwritecontext.sip.in
+++ b/python/core/qgsreadwritecontext.sip.in
@@ -35,6 +35,16 @@ Returns path resolver for conversion between relative and absolute paths
     void setPathResolver( const QgsPathResolver &resolver );
 %Docstring
 Sets up path resolver for conversion between relative and absolute paths
+%End
+
+    void pushMessage( Qgis::MessageLevel level, const QString &message );
+%Docstring
+append a message to the context
+%End
+
+    QList<QPair<Qgis::MessageLevel, QString>> takeMessages();
+%Docstring
+return the stored messages and remove them
 %End
 
 };
diff --git a/src/app/qgisapp.cpp b/src/app/qgisapp.cpp
index 9b8725fabd8..8cd799de1dd 100644
--- a/src/app/qgisapp.cpp
+++ b/src/app/qgisapp.cpp
@@ -3230,6 +3230,8 @@ void QgisApp::setupConnections()
            this, &QgisApp::showProgress );
   connect( QgsProject::instance(), &QgsProject::loadingLayer,
            this, &QgisApp::showStatusMessage );
+  connect( QgsProject::instance(), &QgsProject::loadingLayerMessages,
+           this, &QgisApp::loadingLayerMessages );
   connect( QgsProject::instance(), &QgsProject::readProject,
            this, &QgisApp::readProject );
   connect( QgsProject::instance(), &QgsProject::writeProject,
@@ -11238,6 +11240,14 @@ void QgisApp::showStatusMessage( const QString &message )
   mStatusBar->showMessage( message );
 }
 
+void QgisApp::loadingLayerMessages( const QString &layerName, const QList<QPair<Qgis::MessageLevel, QString> > &messages )
+{
+  for ( const auto message : messages )
+  {
+    messageBar()->pushMessage( layerName, message.second, message.first );
+  }
+}
+
 void QgisApp::displayMapToolMessage( const QString &message, Qgis::MessageLevel level )
 {
   // remove previous message
diff --git a/src/app/qgisapp.h b/src/app/qgisapp.h
index c82d1b580c9..db5da5a3c3e 100644
--- a/src/app/qgisapp.h
+++ b/src/app/qgisapp.h
@@ -926,6 +926,8 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
     void showProgress( int progress, int totalSteps );
     void showStatusMessage( const QString &message );
 
+    void loadingLayerMessages( const QString &layerName, const QList<QPair<Qgis::MessageLevel, QString>> &messages );
+
     //! set the active layer
     bool setActiveLayer( QgsMapLayer * );
 
diff --git a/src/core/qgsproject.cpp b/src/core/qgsproject.cpp
index c0a82c9bccf..0c1c55f9c21 100644
--- a/src/core/qgsproject.cpp
+++ b/src/core/qgsproject.cpp
@@ -716,6 +716,11 @@ bool QgsProject::_getMapLayers( const QDomDocument &doc, QList<QDomNode> &broken
       {
         returnStatus = false;
       }
+      const auto messages = context.takeMessages();
+      if ( messages.count() )
+      {
+        emit loadingLayerMessages( tr( "Loading layer %1" ).arg( name ), messages );
+      }
     }
     emit layerLoaded( i + 1, nl.count() );
     i++;
diff --git a/src/core/qgsproject.h b/src/core/qgsproject.h
index ce3bcd52c59..e3d8f88bd1b 100644
--- a/src/core/qgsproject.h
+++ b/src/core/qgsproject.h
@@ -887,7 +887,9 @@ class CORE_EXPORT QgsProject : public QObject, public QgsExpressionContextGenera
      */
     void layerLoaded( int i, int n );
 
-    void loadingLayer( const QString & );
+    void loadingLayer( const QString &layerName );
+
+    void loadingLayerMessages( const QString &layerName, const QList<QPair<Qgis::MessageLevel, QString>> &messages );
 
     //! Emitted when the list of layer which are excluded from map identification changes
     void nonIdentifiableLayersChanged( QStringList nonIdentifiableLayers );
diff --git a/src/core/qgsreadwritecontext.h b/src/core/qgsreadwritecontext.h
index 8fb408db745..296dc74c835 100644
--- a/src/core/qgsreadwritecontext.h
+++ b/src/core/qgsreadwritecontext.h
@@ -19,6 +19,7 @@
 #define QGSREADWRITECONTEXT_H
 
 #include "qgspathresolver.h"
+#include "qgis.h"
 
 /**
  * \class QgsReadWriteContext
@@ -41,8 +42,15 @@ class CORE_EXPORT QgsReadWriteContext
     //! Sets up path resolver for conversion between relative and absolute paths
     void setPathResolver( const QgsPathResolver &resolver ) { mPathResolver = resolver; }
 
+    //! append a message to the context
+    void pushMessage( Qgis::MessageLevel level, const QString &message ) {mMessages.append( qMakePair( level, message ) );}
+
+    //! return the stored messages and remove them
+    QList<QPair<Qgis::MessageLevel, QString>> takeMessages() {return mMessages; mMessages.clear();}
+
   private:
     QgsPathResolver mPathResolver;
+    QList<QPair<Qgis::MessageLevel, QString>> mMessages;
 };
 
 #endif // QGSREADWRITECONTEXT_H