Use const char* for ListView GetColumns()

Author: fido2020

Applications/DeviceManager/main.cpp

@@ -22,8 +22,8 @@ class DeviceModel : public Lemon::GUI::DataModel {
         return devices.size();
     }
 
-    const std::string& ColumnName(int column) const {
-        return columns.at(column).Name();
+    const char* ColumnName(int column) const {
+        return columns.at(column).Name().c_str();
     }
 
 	Lemon::GUI::Variant GetData(int row, int column){

Applications/LemonMonitor/main.cpp

@@ -35,8 +35,8 @@ class ProcessModel : public Lemon::GUI::DataModel {
         return processes.size();
     }
 
-    const std::string& ColumnName(int column) const {
-        return columns.at(column).Name();
+    const char* ColumnName(int column) const {
+        return columns.at(column).Name().c_str();
     }
 
     Lemon::GUI::Variant GetData(int row, int column){

Applications/Shell/menu.cpp

@@ -147,7 +147,7 @@ class MenuModel
 
     int ColumnCount() const override { return 3; }
     int RowCount() const override { return filter.ItemCount(); }
-    const std::string& ColumnName(int) const override { return m_colName; } // We dont display columns
+    const char* ColumnName(int) const override { return m_colName.c_str(); } // We dont display columns
 
     Lemon::GUI::Variant GetData(int row, int column) override {
         switch(column){