Hi i'm using singleton but i did samemitakes when i use singleton. Normally i create static object. But this is not recomendable.
So someine can help me with this code i need to do this:
First thing i am trying to make my _instance like a pointer. Second i am trying initialize it the first time instance is called.
Example for c++:
Qt Code: 
  1. class GlobalClass
  2. {
  3.     int m_value;
  4.   public:
  5.     GlobalClass(int v = 0)
  6.     {
  7.         m_value = v;
  8.     }
  9.     int get_value()
  10.     {
  11.         return m_value;
  12.     }
  13.     void set_value(int v)
  14.     {
  15.         m_value = v;
  16.     }
  17. };
  18.  
  19. // Default initialization
  20. GlobalClass *global_ptr = 0;
  21.  
  22. void foo(void)
  23. {
  24.   // Initialization on first use
  25.   if (!global_ptr)
  26.     global_ptr = new GlobalClass;
  27.   global_ptr->set_value(1);
  28.   cout << "foo: global_ptr is " << global_ptr->get_value() << '\n';
  29. }
  30.  
  31. void bar(void)
  32. {
  33.   if (!global_ptr)
  34.     global_ptr = new GlobalClass;
  35.   global_ptr->set_value(2);
  36.   cout << "bar: global_ptr is " << global_ptr->get_value() << '\n';
  37. }
  38.  
  39. int main()
  40. {
  41.   if (!global_ptr)
  42.     global_ptr = new GlobalClass;
  43.   cout << "main: global_ptr is " << global_ptr->get_value() << '\n';
  44.   foo();
  45.   bar();
  46. }
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Some example similar for QT? I need some example very similiar to this example in c++.