From 57c3d8e8d8f9cb265b39c00a37b7bae9696e0aad Mon Sep 17 00:00:00 2001
From: Jeff Young <jeff@rokeby.ie>
Date: Sat, 15 Aug 2020 21:13:08 +0100
Subject: [PATCH] Make sure preview group gets added to view after a clear.

---
 common/view/view.cpp           | 7 +++++++
 eeschema/sch_view.cpp          | 8 +++-----
 include/view/view.h            | 2 ++
 pcbnew/pcb_base_edit_frame.cpp | 1 +
 pcbnew/router/router_tool.cpp  | 6 +++---
 5 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/common/view/view.cpp b/common/view/view.cpp
index e513d63b39..b19fcdd8bc 100644
--- a/common/view/view.cpp
+++ b/common/view/view.cpp
@@ -1562,6 +1562,13 @@ void VIEW::ClearPreview()
 }
 
 
+void VIEW::InitPreview()
+{
+   m_preview.reset( new KIGFX::VIEW_GROUP() );
+   Add( m_preview.get() );
+}
+
+
 void VIEW::AddToPreview( EDA_ITEM* aItem, bool aTakeOwnership )
 {
    Hide( aItem, false );
diff --git a/eeschema/sch_view.cpp b/eeschema/sch_view.cpp
index 5057c80d47..1a526efda9 100644
--- a/eeschema/sch_view.cpp
+++ b/eeschema/sch_view.cpp
@@ -112,10 +112,9 @@ void SCH_VIEW::DisplaySheet( SCH_SCREEN *aScreen )
 
     ResizeSheetWorkingArea( aScreen );
 
-    m_preview.reset( new KIGFX::VIEW_GROUP() );
-
     Add( m_worksheet.get() );
-    Add( m_preview.get() );
+
+    InitPreview();
 }
 
 
@@ -171,8 +170,7 @@ void SCH_VIEW::DisplayComponent( LIB_PART* aPart )
         Add( &item );
     }
 
-    m_preview.reset( new KIGFX::VIEW_GROUP() );
-    Add( m_preview.get() );
+    InitPreview();
 }
 
 
diff --git a/include/view/view.h b/include/view/view.h
index 4168e7fff4..1e11dd1745 100644
--- a/include/view/view.h
+++ b/include/view/view.h
@@ -663,6 +663,8 @@ public:
 
     std::shared_ptr<VIEW_OVERLAY> MakeOverlay();
 
+    void InitPreview();
+
     void ClearPreview();
     void AddToPreview( EDA_ITEM* aItem, bool aTakeOwnership = true );
 
diff --git a/pcbnew/pcb_base_edit_frame.cpp b/pcbnew/pcb_base_edit_frame.cpp
index fc8d081f75..3d14606732 100644
--- a/pcbnew/pcb_base_edit_frame.cpp
+++ b/pcbnew/pcb_base_edit_frame.cpp
@@ -102,6 +102,7 @@ void PCB_BASE_EDIT_FRAME::SetBoard( BOARD* aBoard )
             m_toolManager->ResetTools( TOOL_BASE::MODEL_RELOAD );
 
         GetCanvas()->GetView()->Clear();
+        GetCanvas()->GetView()->InitPreview();
     }
 
     PCB_BASE_FRAME::SetBoard( aBoard );
diff --git a/pcbnew/router/router_tool.cpp b/pcbnew/router/router_tool.cpp
index 8d9a5bcde8..ccbca68f26 100644
--- a/pcbnew/router/router_tool.cpp
+++ b/pcbnew/router/router_tool.cpp
@@ -1422,6 +1422,9 @@ int ROUTER_TOOL::InlineDrag( const TOOL_EVENT& aEvent )
     controls()->SetAutoPan( true );
     frame()->UndoRedoBlock( true );
 
+    view()->ClearPreview();
+    view()->InitPreview();
+
     while( TOOL_EVENT* evt = Wait() )
     {
         frame()->GetCanvas()->SetCurrentCursor( wxCURSOR_ARROW );
@@ -1456,20 +1459,17 @@ int ROUTER_TOOL::InlineDrag( const TOOL_EVENT& aEvent )
                         previewItem->Move( offset );
                     }
 
-                    view()->Add( previewItem );
                     view()->AddToPreview( previewItem );
                     view()->Hide( drawing, true );
                 }
 
                 previewItem = static_cast<BOARD_ITEM*>( module->Reference().Clone() );
                 previewItem->Move( offset );
-                view()->Add( previewItem );
                 view()->AddToPreview( previewItem );
                 view()->Hide( &module->Reference() );
 
                 previewItem = static_cast<BOARD_ITEM*>( module->Value().Clone() );
                 previewItem->Move( offset );
-                view()->Add( previewItem );
                 view()->AddToPreview( previewItem );
                 view()->Hide( &module->Value() );
             }