Sheet: Make ViewProviderSpreadsheet.h self-contained

and fix a few minor issues

src/Mod/Spreadsheet/Gui/AppSpreadsheetGui.cpp

@@ -37,7 +37,6 @@
 
 #include "DlgSettingsImp.h"
 #include "SheetTableViewAccessibleInterface.h"
-#include "SpreadsheetView.h"
 #include "ViewProviderSpreadsheet.h"
 #include "Workbench.h"
 

src/Mod/Spreadsheet/Gui/ViewProviderSpreadsheet.cpp

@@ -37,7 +37,6 @@
 #include <Gui/View3DInventor.h>
 #include <Mod/Spreadsheet/App/Sheet.h>
 
-#include "SpreadsheetView.h"
 #include "ViewProviderSpreadsheet.h"
 #include "ViewProviderSpreadsheetPy.h"
 
@@ -50,15 +49,12 @@ using namespace Spreadsheet;
 
 PROPERTY_SOURCE(SpreadsheetGui::ViewProviderSheet, Gui::ViewProviderDocumentObject)
 
-ViewProviderSheet::ViewProviderSheet()
-    : Gui::ViewProviderDocumentObject()
-{}
+ViewProviderSheet::ViewProviderSheet() = default;
 
 ViewProviderSheet::~ViewProviderSheet()
 {
     if (!view.isNull()) {
         Gui::getMainWindow()->removeWindow(view);
-        //        delete view;
     }
 }
 
@@ -76,14 +72,31 @@ std::vector<std::string> ViewProviderSheet::getDisplayModes() const
 
 QIcon ViewProviderSheet::getIcon() const
 {
+    // clang-format off
     static const char* const Points_Feature_xpm[] = {
-        "16 16 3 1",        "       c None",    ".      c #000000", "+      c #FFFFFF",
-        "                ", "                ", "................", ".++++.++++.++++.",
-        ".++++.++++.++++.", "................", ".++++.++++.++++.", ".++++.++++.++++.",
-        "................", ".++++.++++.++++.", ".++++.++++.++++.", "................",
-        ".++++.++++.++++.", ".++++.++++.++++.", "................", "                "};
+        "16 16 3 1",
+        "       c None",
+        ".      c #000000",
+        "+      c #FFFFFF",
+        "                ",
+        "                ",
+        "................",
+        ".++++.++++.++++.",
+        ".++++.++++.++++.",
+        "................",
+        ".++++.++++.++++.",
+        ".++++.++++.++++.",
+        "................",
+        ".++++.++++.++++.",
+        ".++++.++++.++++.",
+        "................",
+        ".++++.++++.++++.",
+        ".++++.++++.++++.",
+        "................",
+        "                "};
     QPixmap px(Points_Feature_xpm);
     return px;
+    // clang-format on
 }
 
 bool ViewProviderSheet::setEdit(int ModNum)

src/Mod/Spreadsheet/Gui/ViewProviderSpreadsheet.h

@@ -29,18 +29,12 @@
 #include <Gui/ViewProviderDocumentObject.h>
 #include <Gui/ViewProviderPythonFeature.h>
 #include <Mod/Spreadsheet/SpreadsheetGlobal.h>
+#include <Mod/Spreadsheet/Gui/SpreadsheetView.h>
 
 
-namespace Spreadsheet
-{
-class Sheet;
-}
-
 namespace SpreadsheetGui
 {
 
-class SheetView;
-
 class SpreadsheetGuiExport ViewProviderSheet: public Gui::ViewProviderDocumentObject
 {
     PROPERTY_HEADER_WITH_OVERRIDE(SpreadsheetGui::ViewProviderSheet);

src/Mod/Spreadsheet/Gui/ViewProviderSpreadsheetPyImp.cpp

@@ -23,7 +23,6 @@
 #include "PreCompiled.h"
 
 // clang-format off
-#include "SpreadsheetView.h"
 #include "ViewProviderSpreadsheetPy.h"
 #include "ViewProviderSpreadsheetPy.cpp"
 // clang-format on
@@ -56,7 +55,6 @@ PyObject* ViewProviderSpreadsheetPy::getCustomAttributes(const char* /*attr*/) c
     return nullptr;
 }
 
-
 int ViewProviderSpreadsheetPy::setCustomAttributes(const char* /*attr*/, PyObject* /*obj*/)
 {
     return 0;