Don't clear old footprint till after user has hit OK.

Fixes: lp:1759190
* https://bugs.launchpad.net/kicad/+bug/1759190

include/pcb_base_frame.h

@@ -443,19 +443,19 @@ public:
 
     /**
      * Function LoadModuleFromLibrary
-     * opens a dialog to select a footprint, and loads it into current board.
+     * opens a dialog to select a footprint.
      *
-     * @param aLibrary = the library name to use, or empty string to search
+     * @param aLibrary = the library name to use, or empty string to search all libraries
-     * in all loaded libraries
+     * @param aUseFootprintViewer = true to allow selection by the footprint viewer
-     * @param aTable is the #FP_LIB_TABLE containing the avaiable footprint libraries.
+     */
-     * @param aUseFootprintViewer = true to show the option
+    MODULE* LoadModuleFromLibrary( const wxString& aLibrary, bool aUseFootprintViewer = true );
-     * allowing the footprint selection by the footprint viewer
+
+    /**
+     * Adds the given module to the board.
+     * @param module
      * @param aDC (can be NULL ) = the current Device Context, to draw the new footprint
      */
-    MODULE* LoadModuleFromLibrary( const wxString& aLibrary,
+    void AddModuleToBoard( MODULE* module, wxDC* aDC = nullptr );
-                                   FP_LIB_TABLE*   aTable,
-                                   bool            aUseFootprintViewer = true,
-                                   wxDC*           aDC = NULL );
 
     /**
      * Function SelectFootprintFromLibBrowser

pcbnew/footprint_editor_utils.cpp

@@ -300,15 +300,21 @@ void FOOTPRINT_EDIT_FRAME::Process_Special_Functions( wxCommandEvent& event )
 
     case ID_MODEDIT_NEW_MODULE:
         {
-            if( !Clear_Pcb( true ) )
+            if( GetScreen()->IsModify() && !GetBoard()->IsEmpty() )
+            {
+                if( !IsOK( this, _( "Current Footprint will be lost and this operation cannot be undone. Continue ?" ) ) )
                     break;
-
+            }
-            SetCrossHairPosition( wxPoint( 0, 0 ) );
 
             MODULE* module = CreateNewModule( wxEmptyString );
 
             if( module )        // i.e. if create module command not aborted
             {
+                Clear_Pcb( false );
+
+                SetCrossHairPosition( wxPoint( 0, 0 ) );
+                AddModuleToBoard( module );
+
                 // Initialize data relative to nets and netclasses (for a new
                 // module the defaults are used)
                 // This is mandatory to handle and draw pads
@@ -517,16 +523,26 @@ void FOOTPRINT_EDIT_FRAME::Process_Special_Functions( wxCommandEvent& event )
         break;
 
     case ID_MODEDIT_LOAD_MODULE:
+    {
         wxLogDebug( wxT( "Loading module from library " ) + getLibPath() );
 
-        if( ! Clear_Pcb( true ) )
+        if( GetScreen()->IsModify() && !GetBoard()->IsEmpty() )
+        {
+            if( !IsOK( this, _( "Current Footprint will be lost and this operation cannot be undone. Continue ?" ) ) )
+                break;
+        }
+
+        MODULE* module = LoadModuleFromLibrary( GetCurrentLib() );
+
+        if( !module )
             break;
 
+        Clear_Pcb( false );
+
         SetCrossHairPosition( wxPoint( 0, 0 ) );
+        AddModuleToBoard( module );
 
-        LoadModuleFromLibrary( GetCurrentLib(), Prj().PcbFootprintLibs(), true );
+        if( GetBoard()->m_Modules )
-
-        if( GetBoard() && GetBoard()->m_Modules )
         {
             GetBoard()->m_Modules->ClearFlags();
 
@@ -562,7 +578,7 @@ void FOOTPRINT_EDIT_FRAME::Process_Special_Functions( wxCommandEvent& event )
 
         updateView();
         m_canvas->Refresh();
-
+    }
         break;
 
     case ID_MODEDIT_PAD_SETTINGS:

pcbnew/footprint_viewer_frame.cpp

@@ -807,12 +807,10 @@ void FOOTPRINT_VIEWER_FRAME::SelectCurrentFootprint( wxCommandEvent& event )
 {
     wxString curr_nickname = getCurNickname();
     MODULE*  oldmodule = GetBoard()->m_Modules;
-    MODULE*  module = LoadModuleFromLibrary( curr_nickname, Prj().PcbFootprintLibs(), false );
+    MODULE*  module = LoadModuleFromLibrary( curr_nickname, false );
 
     if( module )
     {
-        module->SetPosition( wxPoint( 0, 0 ) );
-
         // Only one footprint allowed: remove the previous footprint (if exists)
         if( oldmodule )
         {
@@ -820,6 +818,9 @@ void FOOTPRINT_VIEWER_FRAME::SelectCurrentFootprint( wxCommandEvent& event )
             delete oldmodule;
         }
 
+        SetCrossHairPosition( wxPoint( 0, 0 ) );
+        AddModuleToBoard( module );
+
         setCurFootprintName( module->GetFPID().GetLibItemName() );
 
         wxString nickname = module->GetFPID().GetLibNickname();

pcbnew/load_select_footprint.cpp

@@ -160,13 +160,10 @@ wxString PCB_BASE_FRAME::SelectFootprintFromLibBrowser()
 }
 
 
-MODULE* PCB_BASE_FRAME::LoadModuleFromLibrary( const wxString& aLibrary,
+MODULE* PCB_BASE_FRAME::LoadModuleFromLibrary( const wxString& aLibrary, bool aUseFootprintViewer )
-                                               FP_LIB_TABLE*   aTable,
-                                               bool            aUseFootprintViewer,
-                                               wxDC*           aDC )
 {
+    FP_LIB_TABLE*   fpTable = Prj().PcbFootprintLibs();
     MODULE*         module = NULL;
-    wxPoint         curspos = GetCrossHairPosition();
     wxString        moduleName, keys;
     const wxString& libName = aLibrary;
     bool            allowWildSeach = true;
@@ -207,7 +204,7 @@ MODULE* PCB_BASE_FRAME::LoadModuleFromLibrary( const wxString& aLibrary,
         // If the footprints are already in the cache, ReadFootprintFiles() will return
         // immediately.
         WX_PROGRESS_REPORTER progressReporter( this, _( "Loading Footprint Libraries" ), 2 );
-        MList.ReadFootprintFiles( aTable, libName.length() ? &libName : NULL, &progressReporter );
+        MList.ReadFootprintFiles( fpTable, libName.length() ? &libName : NULL, &progressReporter );
         progressReporter.Show( false );
 
         if( MList.GetErrorCount() )
@@ -217,7 +214,7 @@ MODULE* PCB_BASE_FRAME::LoadModuleFromLibrary( const wxString& aLibrary,
         {
             allowWildSeach = false;
             keys = moduleName;
-            moduleName = SelectFootprint( this, libName, wxEmptyString, keys, aTable );
+            moduleName = SelectFootprint( this, libName, wxEmptyString, keys, fpTable );
 
             if( moduleName.IsEmpty() )  // Cancel command
             {
@@ -228,7 +225,7 @@ MODULE* PCB_BASE_FRAME::LoadModuleFromLibrary( const wxString& aLibrary,
         else                        // Selection wild card
         {
             allowWildSeach = false;
-            moduleName     = SelectFootprint( this, libName, moduleName, wxEmptyString, aTable );
+            moduleName     = SelectFootprint( this, libName, moduleName, wxEmptyString, fpTable );
 
             if( moduleName.IsEmpty() )
             {
@@ -261,7 +258,7 @@ MODULE* PCB_BASE_FRAME::LoadModuleFromLibrary( const wxString& aLibrary,
         wxString wildname = wxChar( '*' ) + moduleName + wxChar( '*' );
         moduleName = wildname;
 
-        moduleName = SelectFootprint( this, libName, moduleName, wxEmptyString, aTable );
+        moduleName = SelectFootprint( this, libName, moduleName, wxEmptyString, fpTable );
 
         if( moduleName.IsEmpty() )
         {
@@ -286,23 +283,29 @@ MODULE* PCB_BASE_FRAME::LoadModuleFromLibrary( const wxString& aLibrary,
         }
     }
 
-    SetCrossHairPosition( curspos );
+    if( module )
-    m_canvas->MoveCursorToCrossHair();
+    {
+        lastComponentName = moduleName;
+        AddHistoryComponentName( HistoryList, moduleName );
+    }
 
+    return module;
+}
+
+
+void PCB_BASE_FRAME::AddModuleToBoard( MODULE* module, wxDC* aDC )
+{
     if( module )
     {
         GetBoard()->Add( module, ADD_APPEND );
 
-        lastComponentName = moduleName;
-        AddHistoryComponentName( HistoryList, moduleName );
-
         module->SetFlags( IS_NEW );
         module->SetLink( 0 );
 
         if( IsGalCanvasActive() )
             module->SetPosition( wxPoint( 0, 0 ) ); // cursor in GAL may not be initialized at the moment
         else
-            module->SetPosition( curspos );
+            module->SetPosition( GetCrossHairPosition() );
 
         module->SetTimeStamp( GetNewTimeStamp() );
         GetBoard()->m_Status_Pcb = 0;
@@ -322,8 +325,6 @@ MODULE* PCB_BASE_FRAME::LoadModuleFromLibrary( const wxString& aLibrary,
         if( aDC )
             module->Draw( m_canvas, aDC, GR_OR );
     }
-
-    return module;
 }
 
 

pcbnew/onleftclick.cpp

@@ -368,13 +368,16 @@ void PCB_EDIT_FRAME::OnLeftClick( wxDC* aDC, const wxPoint& aPosition )
         if( (curr_item == NULL) || (curr_item->GetFlags() == 0) )
         {
             m_canvas->MoveCursorToCrossHair();
-            curr_item = (BOARD_ITEM*) LoadModuleFromLibrary(
+            MODULE* module = LoadModuleFromLibrary( wxEmptyString, Prj().PcbFootprintLibs() );
-                    wxEmptyString, Prj().PcbFootprintLibs(), true, aDC );
 
-            SetCurItem( curr_item );
+            SetCurItem( (BOARD_ITEM*) module );
 
-            if( curr_item )
+            if( module )
-                StartMoveModule( (MODULE*) curr_item, aDC, false );
+            {
+                m_canvas->MoveCursorToCrossHair();
+                AddModuleToBoard( module, aDC );
+                StartMoveModule( module, aDC, false );
+            }
         }
         else if( curr_item->Type() == PCB_MODULE_T )
         {

pcbnew/tools/pcb_editor_control.cpp

@@ -467,14 +467,12 @@ int PCB_EDITOR_CONTROL::PlaceModule( const TOOL_EVENT& aEvent )
             if( !module )
             {
                 // Pick the module to be placed
-                module = m_frame->LoadModuleFromLibrary( wxEmptyString,
+                module = m_frame->LoadModuleFromLibrary( wxEmptyString );
-                                                         m_frame->Prj().PcbFootprintLibs(),
-                                                         true, NULL );
 
                 if( module == NULL )
                     continue;
 
-                // NOTE: Module has been already added in LoadModuleFromLibrary(),
+                m_frame->AddModuleToBoard( module );
                 commit.Added( module );
                 module->SetPosition( wxPoint( cursorPos.x, cursorPos.y ) );
                 m_toolMgr->RunAction( PCB_ACTIONS::selectItem, true, module );