diff --git a/src/directories.cc b/src/directories.cc
index 82d9dba..80db07c 100644
--- a/src/directories.cc
+++ b/src/directories.cc
@@ -3,7 +3,7 @@
 #include "logging.h"
 #include "singletons.h"
 #include <algorithm>
-#include "boost/algorithm/string.hpp"
+#include <unordered_set>
 
 #include <iostream> //TODO: remove
 using namespace std; //TODO: remove
@@ -19,31 +19,46 @@ Directories::Directories() {
   tree_store = Gtk::TreeStore::create(column_record);
   tree_view.set_model(tree_store);
   tree_view.append_column("", column_record.name);
-  tree_store->set_sort_column(0, Gtk::SortType::SORT_ASCENDING);
+  tree_store->set_sort_column(column_record.id, Gtk::SortType::SORT_ASCENDING);
   
   tree_view.signal_row_activated().connect([this](const Gtk::TreeModel::Path& path, Gtk::TreeViewColumn* column){
     INFO("Directory navigation");
     auto iter = tree_store->get_iter(path);
     if (iter) {
-      Gtk::TreeModel::Row row = *iter;
-      std::string upath = Glib::ustring(row[column_record.path]);
-      boost::filesystem::path fs_path(upath);
-      if (boost::filesystem::is_directory(fs_path)) {
+      auto path_str=iter->get_value(column_record.path);
+      if (boost::filesystem::is_directory(boost::filesystem::path(path_str))) {
         tree_view.row_expanded(path) ? tree_view.collapse_row(path) : tree_view.expand_row(path, false);
       } else {
-        std::stringstream sstm;
-        sstm << row[column_record.path];
         if(on_row_activated)
-          on_row_activated(sstm.str());
+          on_row_activated(path_str);
       }
     }
   });
+  
+  tree_view.signal_test_expand_row().connect([this](const Gtk::TreeModel::iterator& iter, const Gtk::TreeModel::Path& path){
+    if(iter->children().begin()->get_value(column_record.path)=="") {
+      add_path(iter->get_value(column_record.path), *iter);
+    }
+    return false;
+  });
+  tree_view.signal_row_collapsed().connect([this](const Gtk::TreeModel::iterator& iter, const Gtk::TreeModel::Path& path){
+    auto children=iter->children();
+    if(children) {
+      while(children) {
+        tree_store->erase(children.begin());
+      }
+      tree_store->append(iter->children());
+    }
+  });
 }
 
 void Directories::open_folder(const boost::filesystem::path& dir_path) {
+  if(dir_path!="")
+    tree_store->clear();
+  
   auto new_path=dir_path;
   INFO("Open folder");
-  if(new_path=="") {
+  if(dir_path=="") {
     if(current_path=="")
       return;
     new_path=current_path;
@@ -56,8 +71,6 @@ void Directories::open_folder(const boost::filesystem::path& dir_path) {
     });
   }
   
-  tree_store->clear();
-  
   if(dir_path!="")
     cmake=std::unique_ptr<CMake>(new CMake(new_path));
   auto project=cmake->get_functions_parameters("project");
@@ -65,19 +78,44 @@ void Directories::open_folder(const boost::filesystem::path& dir_path) {
     tree_view.get_column(0)->set_title(project[0].second[0]);
   else
     tree_view.get_column(0)->set_title("");
-  add_paths(new_path, Gtk::TreeModel::Row(), 0);
+  add_path(new_path, Gtk::TreeModel::Row());
 
   for(auto &path: expanded_paths)
     tree_view.expand_row(path, false);
     
   current_path=new_path;
   
-  if(selected_path!="")
-    select_path(selected_path);
   DEBUG("Folder opened");
 }
 
 void Directories::select_path(const boost::filesystem::path &path) {
+  if(current_path=="")
+    return;
+    
+  if(path.string().substr(0, current_path.string().size())!=current_path.string())
+    return;
+  
+  if(boost::filesystem::is_directory(path))
+    return;
+    
+  std::list<boost::filesystem::path> paths;
+  auto parent_path=path.parent_path();
+  paths.emplace_front(parent_path);
+  while(parent_path!=current_path) {
+    parent_path=parent_path.parent_path();
+    paths.emplace_front(parent_path);
+  }
+
+  for(auto &a_path: paths) {
+    tree_store->foreach_iter([this, &a_path](const Gtk::TreeModel::iterator& iter){
+      if(iter->get_value(column_record.path)==a_path.string()) {
+        add_path(a_path, *iter);
+        return true;
+      }
+      return false;
+    });
+  }
+  
   tree_store->foreach_iter([this, &path](const Gtk::TreeModel::iterator& iter){
     if(iter->get_value(column_record.path)==path.string()) {
       auto tree_path=Gtk::TreePath(iter);
@@ -106,37 +144,54 @@ bool Directories::ignored(std::string path) {
   return false;
 }
 
-void Directories::add_paths(const boost::filesystem::path& dir_path, const Gtk::TreeModel::Row &parent, unsigned row_id) {
-  boost::filesystem::directory_iterator end_itr;
-  Gtk::TreeModel::Row child;
-  Gtk::TreeModel::Row row;
-  DEBUG("");
-  // Fill the treeview
-  for(boost::filesystem::directory_iterator itr(dir_path);itr != end_itr;++itr) {   
-    if (!ignored(itr->path().filename().string())) {
-      if (boost::filesystem::is_directory(itr->status())) {
-        if (boost::filesystem::canonical(itr->path()) > boost::filesystem::canonical(dir_path)) {  // is child
-          child = *(tree_store->append(parent.children()));
-          std::string col_id("a"+itr->path().filename().string());
-          child[column_record.id] = col_id;
-          child[column_record.name] =  itr->path().filename().string();
-          child[column_record.path] = itr->path().string();
-          add_paths(itr->path(), child, row_id);
-        } else {
-          row = *(tree_store->append());
-          std::string col_id("a"+itr->path().filename().string());
-          row[column_record.path] = itr->path().string();
-          row[column_record.id] = col_id;
-          row[column_record.name] =  itr->path().filename().string();
-          add_paths(itr->path(), parent, row_id);
+void Directories::add_path(const boost::filesystem::path& dir_path, const Gtk::TreeModel::Row &parent) {
+  auto children=tree_store->children();
+  if(parent)
+    children=parent.children();
+  if(children) {
+    if(children.begin()->get_value(column_record.path)=="") {
+      tree_store->erase(parent->children().begin());
+    }
+  }
+  std::unordered_set<std::string> not_deleted;
+  boost::filesystem::directory_iterator end_it;
+  for(boost::filesystem::directory_iterator it(dir_path);it!=end_it;it++) {
+    auto filename=it->path().filename().string();
+    if (!ignored(filename)) {
+      bool already_added=false;
+      if(children) {
+        for(auto &child: children) {
+          if(child.get_value(column_record.name)==filename) {
+            not_deleted.emplace(filename);
+            already_added=true;
+            break;
+          }
+        }
+      }
+      if(!already_added) {
+        auto child = tree_store->append(children);
+        not_deleted.emplace(filename);
+        child->set_value(column_record.name, filename);
+        child->set_value(column_record.path, it->path().string());
+        if (boost::filesystem::is_directory(*it)) {
+          child->set_value(column_record.id, "a"+filename);
+          tree_store->append(child->children());
         }
-      } else {  // is a file
-        child = *(tree_store->append(parent.children()));
-        std::string col_id("b"+itr->path().filename().string());
-        child[column_record.id] = col_id;
-        child[column_record.name] = itr->path().filename().string();
-        child[column_record.path] = itr->path().string();
+        else
+          child->set_value(column_record.id, "b"+filename);
       }
     }
   }
+  if(children) {
+    auto last_it=children.begin();
+    for(auto it=children.begin();it!=children.end();it++) {
+      if(not_deleted.count(it->get_value(column_record.name))==0) {
+        tree_store->erase(it);
+        it=last_it;
+      }
+      last_it=it;
+    }
+  }
+  else
+    tree_store->append(children);
 }
diff --git a/src/directories.h b/src/directories.h
index d8dcb77..4b7b557 100644
--- a/src/directories.h
+++ b/src/directories.h
@@ -22,9 +22,9 @@ public:
       add(name);
       add(path);
     }
-    Gtk::TreeModelColumn<Glib::ustring> id;
-    Gtk::TreeModelColumn<Glib::ustring> name;
-    Gtk::TreeModelColumn<Glib::ustring> path;
+    Gtk::TreeModelColumn<std::string> id;
+    Gtk::TreeModelColumn<std::string> name;
+    Gtk::TreeModelColumn<std::string> path;
   };
 
   Directories();
@@ -36,7 +36,7 @@ public:
   boost::filesystem::path current_path;
   
 private:
-  void add_paths(const boost::filesystem::path& dir_path, const Gtk::TreeModel::Row &row, unsigned depth);
+  void add_path(const boost::filesystem::path& dir_path, const Gtk::TreeModel::Row &row);
   bool ignored(std::string path);
   Gtk::TreeView tree_view;
   Glib::RefPtr<Gtk::TreeStore> tree_store;