First implementation of a tree view in the FListView class

ChangeLog

@@ -1,5 +1,8 @@
-2017-10-02  Markus Gans  <guru.mail@muenster.de>
+2017-10-14  Markus Gans  <guru.mail@muenster.de>
 	* Fixed a bug in the FObject check of parent objects
+	* Replace the deprecated readdir_r function (CVE-2013-4237)
+	* First implementation of a tree view in the FListView 
+	  class (alpha state)
 
 2017-10-02  Markus Gans  <guru.mail@muenster.de>
 	* DECSCUSR - Set Cursor Style support for VTE >= 0.40.0 and 

examples/treeview.cpp

@@ -1,4 +1,23 @@
-// File: treeview.cpp
+/************************************************************************
+* treeview.cpp - Example of a FListView widget with a tree hierarchy    *
+*                                                                       *
+* This file is part of the Final Cut widget toolkit                     *
+*                                                                       *
+* Copyright 2017 Markus Gans                                            *
+*                                                                       *
+* The Final Cut is free software; you can redistribute it and/or modify *
+* it under the terms of the GNU General Public License as published by  *
+* the Free Software Foundation; either version 3 of the License, or     *
+* (at your option) any later version.                                   *
+*                                                                       *
+* The Final Cut is distributed in the hope that it will be useful,      *
+* but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+* GNU General Public License for more details.                          *
+*                                                                       *
+* You should have received a copy of the GNU General Public License     *
+* along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+************************************************************************/
 
 #include <iostream>
 #include <fstream>
@@ -27,29 +46,64 @@ class Treeview : public FDialog
     ~Treeview();
 
   private:
+    // Typedefs
+    struct TreeItem;  // forward declaration
+
     // Disable copy constructor
     Treeview (const Treeview&);
     // Disable assignment operator (=)
     Treeview& operator = (const Treeview&);
 
+    // Method
+    void adjustSize();
+
     // Event handlers
     void onClose (FCloseEvent*);
 
     // Callback methods
     void cb_exitApp (FWidget*, data_ptr);
+
+    // Data Members
+    FListView* listView;
+    FButton*   Quit;
+};
+#pragma pack(pop)
+
+
+//----------------------------------------------------------------------
+// struct Treeview::TreeItem
+//----------------------------------------------------------------------
+
+#pragma pack(push)
+#pragma pack(1)
+struct Treeview::TreeItem
+{
+  const char* const* begin() const
+  { return &name; }
+
+  const char* const* end() const
+  { return &density + 1; }
+
+  // Data Members
+  const char* name;
+  const char* population;
+  const char* density;
+  TreeItem*   child_element;
 };
 #pragma pack(pop)
 
 //----------------------------------------------------------------------
 Treeview::Treeview (FWidget* parent)
   : FDialog(parent)
+  , listView()
+  , Quit()
 {
   // Create FListView object
-  FListView* listView = new FListView (this);
+  listView = new FListView (this);
-  listView->setGeometry(2, 1, 33, 14);
+  listView->setGeometry(2, 1, 53, 14);
 
   // Add columns to the view
-  listView->addColumn ("Name");
+  listView->addColumn ("Name", 23);
   listView->addColumn ("Population");
   listView->addColumn ("Density/km²");
 
@@ -61,40 +115,165 @@ Treeview::Treeview (FWidget* parent)
   listView->setTreeView();
 
   // Populate FListView with a list of items
-  std::string continent[][3] =
+  static TreeItem africa[] =
   {
-    { "Africa", "944,000,000", "31.2" },
+    { "Algeria", "40,400,000", "15.9", 0 },
-    { "Asia", "4,010,000,000", "90.3" },
+    { "Angola", "25,789,024", "20.69", 0 },
-    { "Europe", "733,000,000", "69.9" },
+    { "Botswana", "2,250,260", "3.7", 0 },
-    { "North America", "523,000,000", "21" },
+    { "Cameroon", "22,534,532", "39.7", 0 },
-    { "South America", "381,000,000", "21.4" },
+    { "Chad", "13,670,084", "8.6", 0 },
-    { "Antarctica", "1000", "0" },
+    { "Egypt", "94,666,000", "87", 0 },
-    { "Australia/Oceania", "34,000,000", "4" }
+    { "Ethiopia", "102,374,044", "92.7", 0 },
+    { "Ivory Coast", "23,740,424", "63.9", 0 },
+    { "Libya", "6,541,948", "3.55", 0 },
+    { "Madagascar", "24,430,325", "35.2", 0 },
+    { "Mali", "14,517,176", "11.7", 0 },
+    { "Mauritania", "4,301,018", "3.4", 0 },
+    { "Mozambique", "24,692,144", "28.7", 0 },
+    { "Namibia", "2,113,077", "2.54", 0 },
+    { "Niger", "20,672,987", "12.1", 0 },
+    { "Nigeria", "185,989,640", "197.2", 0 },
+    { "Somalia", "14,317,996", "19.31", 0 },
+    { "South Africa", "54,956,900", "42.4", 0 },
+    { "South Sudan", "12,340,000", "13.33", 0 },
+    { "Sudan", "39,578,828", "21.3", 0 },
+    { "Tanzania", "51,820,00", "47.5", 0 },
+    { "Zambia", "16,212,000", "17.2", 0 },
+    { 0, 0, 0, 0 }
   };
 
-  const int lastItem = int(sizeof(continent) / sizeof(continent[0])) - 1;
+  static TreeItem asia[] =
-
-  for (int i = 0; i <= lastItem; i++)
   {
-    FStringList line (&continent[i][0], &continent[i][0] + 3);
+    { "Afghanistan", "34,656,032", "49.88", 0 },
-    listView->insert (line);
+    { "China", "1,403,500,365", "145.0", 0 },
+    { "India", "1,324,171,354", "393.9", 0 },
+    { "Indonesia", "261,115,456", "124.66", 0 },
+    { "Iran", "80,829,192", "48.0", 0 },
+    { "Iraq", "37,202,572", "82.7", 0 },
+    { "Japan", "126,740,000", "336.0", 0 },
+    { "Kazakhstan", "17,987,736", "6.49", 0 },
+    { "Mongolia", "3,081,677", "1.97", 0 },
+    { "Myanmar", "51,486,253", "76.0", 0 },
+    { "Pakistan", "207,774,520", "244.4", 0 },
+    { "Russia", "144,463,451", "8.4", 0 },
+    { "Saudi Arabia", "33,000,000", "15.0", 0 },
+    { "Thailand", "68,863,514", "132.1", 0 },
+    { "Turkey", "79,814,871", "102.0", 0 },
+    { "Turkmenistan", "5,662,544", "10.5", 0 },
+    { "Uzbekistan", "32,979,000", "70.5", 0 },
+    { "Vietnam", "94,569,072", "276.03", 0 },
+    { "Yemen", "27,584,213", "44.7", 0 },
+    { 0, 0, 0, 0 }
+  };
+
+  static TreeItem europe[] =
+  {
+    { "Austria",	"8,794,267",	"104.0", 0 },
+    { "Belarus",	"9,498,700",	"45.8", 0 },
+    { "Bulgaria",	"7,101,859",	"64.9", 0 },
+    { "Czech Republic",	"10,610,947",	"134.0", 0 },
+    { "Finland",	"5,506,312",	"16.0", 0 },
+    { "France",	"66,991,000",	"103.0", 0 },
+    { "Germany",	"82,175,700",	"227.0", 0 },
+    { "Greece",	"11,183,716",	"82.0", 0 },
+    { "Hungary",	"9,797,561",	"105.3", 0 },
+    { "Iceland",	"332,529",	"3.2", 0 },
+    { "Italy",	"60,589,445",	"201.3", 0 },
+    { "Norway",	"5,267,146",	"15.8", 0 },
+    { "Poland",	"38,634,007",	"123.0", 0 },
+    { "Portugal",	"10,309,573",	"115.0", 0 },
+    { "Romania",	"19,638,000",	"84.4", 0 },
+    { "Serbia",	"7,058,322",	"91.1", 0 },
+    { "Spain", "46,468,102",	"92.0", 0 },
+    { "Sweden",	"10,065,389",	"22.0", 0 },
+    { "United Kingdom",	"65,648,000", "270.7", 0 },
+    { 0, 0, 0, 0 }
+  };
+
+  static TreeItem north_america[] =
+  {
+    { "Canada", "35,151,728", "3.92", 0 },
+    { "Cuba", "11,239,224", "102.3", 0 },
+    { "Greenland", "56,483", "0.028", 0 },
+    { "Guatemala", "16,582,469", "129.0", 0 },
+    { "Honduras", "9,112,867", "64.0", 0 },
+    { "Mexico", "119,530,753", "61.0", 0 },
+    { "Nicaragua", "6,167,237", "51.0", 0 },
+    { "USA", "325,365,189", "35.0", 0 },
+    { 0, 0, 0, 0 }
+  };
+
+  static TreeItem south_america[] =
+  {
+    { "Argentina", "43,847,430", "14.4", 0 },
+    { "Bolivia", "11,410,651", "10.4", 0 },
+    { "Brazil", "208,064,000", "24.35", 0 },
+    { "Chile", "18,006,407", "24.0", 0 },
+    { "Colombia", "49,364,592", "40.74", 0 },
+    { "Ecuador", "16,385,068", "58.95", 0 },
+    { "Guyana", "773,303", "3.502", 0 },
+    { "Paraguay", "6,725,308", "17.2", 0 },
+    { "Peru", "31,826,018", "23.0", 0 },
+    { "Venezuela", "31,568,179", "33.75", 0 },
+    { 0, 0, 0, 0 }
+  };
+
+  static TreeItem oceania[] =
+  {
+    { "Australia", "24,675,900", "3.2", 0 },
+    { "Papua New Guinea", "7,059,653", "15.0", 0 },
+    { "Papua", "3,486,432", "11.0", 0 },
+    { "New Zealand", "4,823,090", "17.5", 0 },
+    { "West Papua", "877,437", "6.3", 0 },
+    { "Solomon Islands", "599,419", "18.1", 0 },
+    { "New Caledonia", "268,767", "14.5", 0 },
+    { "Fiji", "898,76", "46.4", 0 },
+    { "Hawaii", "1,428,557", "82.6", 0 },
+    { "Vanuatu", "270,402", "19.7", 0 },
+    { "French Polynesia", "280,208", "76.0", 0 },
+    { "Samoa", "192,342", "68.0", 0 },
+    { "Kiribati", "110,136", "152.0", 0 },
+    { 0, 0, 0, 0 }
+  };
+
+  static TreeItem continent[] =
+  {
+    { "Africa", "944,000,000", "31.2", africa },
+    { "Asia", "4,010,000,000", "90.3", asia },
+    { "Europe", "733,000,000", "69.9", europe },
+    { "North America", "523,000,000", "21", north_america },
+    { "South America", "381,000,000", "21.4", south_america },
+    { "Antarctica", "1000", "0", 0 },
+    { "Australia/Oceania", "34,000,000", "4", oceania },
+    { 0, 0, 0, 0 }
+  };
+
+  TreeItem* continent_list = continent;
+
+  while ( continent_list->name )
+  {
+    TreeItem* country_list = continent_list->child_element;
+    FStringList continent_line (continent_list->begin(), continent_list->end());
+    FObjectIterator iter = listView->insert (continent_line);
+
+    while ( country_list && country_list->name )
+    {
+      FStringList country_line (country_list->begin(), country_list->end());
+      listView->insert (country_line, iter);
+      country_list++;
+    }
+
+    continent_list++;
   }
 
-
+  FObjectIterator iter = listView->beginOfList();
-  FObjectIterator iter_africa = listView->beginOfList();
+  FObjectIterator iter_africa = iter++;
-  std::string egypt[3] = { "Egypt", "94,666,000", "87" };
-  FStringList egypt_line (&egypt[0], &egypt[0] + 3);
-  //FObjectIterator iter_africa = listView->insert (egypt_line);
-  listView->insert (egypt_line, iter_africa);
-
   FListViewItem* item_africa = static_cast<FListViewItem*>(*iter_africa);
-  FObjectIterator iter_egypt = item_africa->begin();
+  item_africa->expand();
-  FListViewItem* item_egypt = static_cast<FListViewItem*>(*iter_egypt);
+
-item_egypt = item_egypt;
-item_africa->expand();
 
   // Quit button
-  FButton* Quit = new FButton (this);
+  Quit = new FButton (this);
   Quit->setGeometry(24, 16, 10, 1);
   Quit->setText (L"&Quit");
 
@@ -110,6 +289,27 @@ item_africa->expand();
 Treeview::~Treeview()  // destructor
 { }
 
+//----------------------------------------------------------------------
+void Treeview::adjustSize()
+{
+  int h = getParentWidget()->getHeight() - 4;
+  setHeight (h, false);
+  int X = int((getParentWidget()->getWidth() - getWidth()) / 2);
+
+  if ( X < 1 )
+    X = 1;
+
+  setX (X, false);
+
+  if ( listView )
+    listView->setHeight (getHeight() - 6, false);
+
+  if ( Quit )
+    Quit->setY(getHeight() - 4);
+
+  FDialog::adjustSize();
+}
+
 //----------------------------------------------------------------------
 void Treeview::onClose (FCloseEvent* ev)
 {
@@ -142,7 +342,7 @@ int main (int argc, char* argv[])
   // Create main dialog object
   Treeview d(&app);
   d.setText (L"Continents");
-  d.setGeometry (int(1 + (app.getWidth() - 37) / 2), 3, 37, 20);
+  d.setGeometry (int(1 + (app.getWidth() - 57) / 2), 3, 57, 20);
   d.setShadow();
 
   // Set dialog d as main widget

include/final/flistview.h

@@ -1,31 +1,48 @@
-// File: flistview.h
+/************************************************************************
-// Provides: class FListViewItem
+* flistview.h - Widget FListView and FListViewItem                      *
-//           class FListView
+*                                                                       *
-//
+* This file is part of the Final Cut widget toolkit                     *
-//  Inheritance diagram
+*                                                                       *
-//  ═══════════════════
+* Copyright 2017 Markus Gans                                            *
-//
+*                                                                       *
-// ▕▔▔▔▔▔▔▔▔▔▏ ▕▔▔▔▔▔▔▔▔▔▏
+* The Final Cut is free software; you can redistribute it and/or modify *
-// ▕ FObject ▏ ▕  FTerm  ▏
+* it under the terms of the GNU General Public License as published by  *
-// ▕▁▁▁▁▁▁▁▁▁▏ ▕▁▁▁▁▁▁▁▁▁▏
+* the Free Software Foundation; either version 3 of the License, or     *
-//      ▲           ▲
+* (at your option) any later version.                                   *
-//      │           │
+*                                                                       *
-//      └─────┬─────┘
+* The Final Cut is distributed in the hope that it will be useful,      *
-//            │
+* but WITHOUT ANY WARRANTY; without even the implied warranty of        *
-//       ▕▔▔▔▔▔▔▔▔▏
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
-//       ▕ FVTerm ▏
+* GNU General Public License for more details.                          *
-//       ▕▁▁▁▁▁▁▁▁▏
+*                                                                       *
-//            ▲
+* You should have received a copy of the GNU General Public License     *
-//            │
+* along with this program.  If not, see <http://www.gnu.org/licenses/>. *
-//       ▕▔▔▔▔▔▔▔▔▔▏           ▕▔▔▔▔▔▔▔▔▔▏
+************************************************************************/
-//       ▕ FWidget ▏           ▕ FObject ▏
+
-//       ▕▁▁▁▁▁▁▁▁▁▏           ▕▁▁▁▁▁▁▁▁▁▏
+/*  Inheritance diagram
-//            ▲                     ▲
+ *  ═══════════════════
-//            │                     │
+ *
-//      ▕▔▔▔▔▔▔▔▔▔▔▔▏1     *▕▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▏
+ * ▕▔▔▔▔▔▔▔▔▔▏ ▕▔▔▔▔▔▔▔▔▔▏
-//      ▕ FListView ▏- - - -▕ FListViewItem ▏
+ * ▕ FObject ▏ ▕  FTerm  ▏
-//      ▕▁▁▁▁▁▁▁▁▁▁▁▏       ▕▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▏
+ * ▕▁▁▁▁▁▁▁▁▁▏ ▕▁▁▁▁▁▁▁▁▁▏
-//
+ *      ▲           ▲
+ *      │           │
+ *      └─────┬─────┘
+ *            │
+ *       ▕▔▔▔▔▔▔▔▔▏
+ *       ▕ FVTerm ▏
+ *       ▕▁▁▁▁▁▁▁▁▏
+ *            ▲
+ *            │
+ *       ▕▔▔▔▔▔▔▔▔▔▏           ▕▔▔▔▔▔▔▔▔▔▏
+ *       ▕ FWidget ▏           ▕ FObject ▏
+ *       ▕▁▁▁▁▁▁▁▁▁▏           ▕▁▁▁▁▁▁▁▁▁▏
+ *            ▲                     ▲
+ *            │                     │
+ *      ▕▔▔▔▔▔▔▔▔▔▔▔▏1     *▕▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▏
+ *      ▕ FListView ▏- - - -▕ FListViewItem ▏
+ *      ▕▁▁▁▁▁▁▁▁▁▁▁▏       ▕▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▏
+ */
 
 #ifndef FLISTVIEW_H
 #define FLISTVIEW_H
@@ -90,6 +107,7 @@ class FListViewItem : public FObject
     FObjectIterator  appendItem (FListViewItem*);
     void             replaceControlCodes();
     int              getVisibleLines();
+    void             resetVisibleLineCounter();
 
     // Data Member
     FStringList       column_list;
@@ -100,6 +118,7 @@ class FListViewItem : public FObject
 
     // Friend class
     friend class FListView;
+    friend class FListViewIterator;
 };
 #pragma pack(pop)
 
@@ -122,6 +141,86 @@ inline bool FListViewItem::isExpandable()
 { return expandable; }
 
 
+//----------------------------------------------------------------------
+// class FListViewIterator
+//----------------------------------------------------------------------
+
+#pragma pack(push)
+#pragma pack(1)
+
+class FListViewIterator
+{
+  public:
+    // Typedefs
+    typedef std::list<FObject*>         FObjectList;
+    typedef FObjectList::iterator       FObjectIterator;
+    typedef std::stack<FObjectIterator> FObjectIteratorStack;
+
+    // Constructor
+    FListViewIterator ();
+    FListViewIterator (FObjectIterator);
+
+    // Destructor
+    ~FListViewIterator();
+
+    // Overloaded operators
+    FListViewIterator& operator ++ ();     // prefix
+    FListViewIterator  operator ++ (int);  // postfix
+    FListViewIterator& operator -- ();     // prefix
+    FListViewIterator  operator -- (int);  // postfix
+    FListViewIterator& operator += (int);
+    FListViewIterator& operator -= (int);
+    FObject*&          operator * () const;
+    FObject*           operator -> () const;
+    bool               operator == (const FListViewIterator&) const;
+    bool               operator != (const FListViewIterator&) const;
+
+    // Accessor
+    const char*        getClassName() const;
+    int                getPosition() const;
+
+    // Methods
+    void parentElement();
+
+  private:
+    // Methods
+    void nextElement (FObjectIterator&);
+    void prevElement (FObjectIterator&);
+
+    // Data Members
+    FObjectIteratorStack iter_path;
+    FObjectIterator      node;
+    int                  position;
+};
+#pragma pack(pop)
+
+
+// FListViewIterator inline functions
+//----------------------------------------------------------------------
+inline FObject*& FListViewIterator::operator * () const
+{ return *node; }
+
+//----------------------------------------------------------------------
+inline FObject* FListViewIterator::operator -> () const
+{ return *node; }
+
+//----------------------------------------------------------------------
+inline bool FListViewIterator::operator == (const FListViewIterator& rhs) const
+{ return node == rhs.node; }
+
+//----------------------------------------------------------------------
+inline bool FListViewIterator::operator != (const FListViewIterator& rhs) const
+{ return node != rhs.node; }
+
+//----------------------------------------------------------------------
+inline const char* FListViewIterator::getClassName() const
+{ return "FListViewIterator"; }
+
+//----------------------------------------------------------------------
+inline int FListViewIterator::getPosition() const
+{ return position; }
+
+
 //----------------------------------------------------------------------
 // class FListView
 //----------------------------------------------------------------------
@@ -143,7 +242,7 @@ class FListView : public FWidget
 
     // Accessors
     const char*          getClassName() const;
-    uInt                 getCount() const;
+    uInt                 getCount();
     fc::text_alignment   getColumnAlignment (int) const;
     FString              getColumnText (int) const;
     FListViewItem*       getCurrentItem();
@@ -190,32 +289,13 @@ class FListView : public FWidget
 
   protected:
     // Methods
-    void                 adjustYOffset();
+    void                 adjustViewport();
     void                 adjustSize();
 
   private:
     // Typedef
-    struct Header
+    struct Header;  // forward declaration
-    {
-     public:
-       Header()
-       : name()
-       , width (0)
-       , fixed_width (false)
-       , alignment (fc::alignLeft)
-       { }
-
-      ~Header()
-       { }
-
-       FString name;
-       int width;
-       bool fixed_width;
-       fc::text_alignment alignment;
-    };
-
     typedef std::vector<Header> headerItems;
-    typedef std::stack<FObjectIterator> FObjectIteratorStack;
 
     // Constants
     static const int USE_MAX_SIZE = -1;
@@ -238,8 +318,14 @@ class FListView : public FWidget
     FObjectIterator      appendItem (FListViewItem*);
     void                 processClick();
     void                 processChanged();
-    FObjectIterator      index2iterator (int);
+    void                 stepForward();
-    void                 nextElement (FObjectIterator&);
+    void                 stepBackward();
+    void                 stepForward (int);
+    void                 stepBackward (int);
+    void                 scrollToX (int);
+    void                 scrollToY (int);
+    void                 scrollTo (const FPoint &);
+    void                 scrollTo (int, int);
 
     // Callback methods
     void                 cb_VBarChange (FWidget*, data_ptr);
@@ -249,7 +335,9 @@ class FListView : public FWidget
     FObjectIterator      root;
     FObjectList          selflist;
     FObjectList          itemlist;
-    FObjectIteratorStack iter_path;
+    FListViewIterator    current_iter;
+    FListViewIterator    first_visible_line;
+    FListViewIterator    last_visible_line;
     headerItems          header;
     FTermBuffer          headerline;
     FScrollbar*          vbar;
@@ -259,9 +347,7 @@ class FListView : public FWidget
     int                  scroll_distance;
     bool                 scroll_timer;
     bool                 tree_view;
-    int                  current;
     int                  xoffset;
-    int                  yoffset;
     int                  nf_offset;
     int                  max_line_width;
 
@@ -271,22 +357,41 @@ class FListView : public FWidget
 #pragma pack(pop)
 
 
+//----------------------------------------------------------------------
+// struct FListView::Header
+//----------------------------------------------------------------------
+
+#pragma pack(push)
+#pragma pack(1)
+struct FListView::Header
+{
+  public:
+    Header()
+      : name()
+      , width (0)
+      , fixed_width (false)
+      , alignment (fc::alignLeft)
+    { }
+
+    ~Header()
+    { }
+
+    FString name;
+    int width;
+    bool fixed_width;
+    fc::text_alignment alignment;
+};
+#pragma pack(pop)
+
+
 // FListView inline functions
 //----------------------------------------------------------------------
 inline const char* FListView::getClassName() const
 { return "FListView"; }
 
-//----------------------------------------------------------------------
-inline uInt FListView::getCount() const
-{ return uInt(itemlist.size()); }
-
 //----------------------------------------------------------------------
 inline FListViewItem* FListView::getCurrentItem()
-{
+{ return static_cast<FListViewItem*>(*current_iter); }
-  FObjectIterator iter = itemlist.begin();
-  std::advance (iter, current - 1);
-  return static_cast<FListViewItem*>(*iter);
-}
 
 //----------------------------------------------------------------------
 inline bool FListView::setTreeView (bool on)
@@ -335,11 +440,7 @@ inline FObject::FObjectIterator FListView::endOfList()
 { return itemlist.end(); }
 
 //----------------------------------------------------------------------
-inline FObject::FObjectIterator FListView::index2iterator (int index)
+inline void FListView::scrollTo (const FPoint& pos)
-{
+{ scrollTo(pos.getX(), pos.getY()); }
-  FObjectIterator iter = itemlist.begin();
-  std::advance (iter, index);
-  return iter;
-}
 
 #endif  // FLISTVIEW_H

src/flistbox.cpp

@@ -1212,7 +1212,7 @@ void FListBox::adjustYOffset()
   int element_count = int(getCount());
 
   if ( getClientHeight() < 0 )
-   beep();
+   return;
 
   if ( element_count == 0 || getClientHeight() <= 0 )
     return;