ceph/src/boost/libs/signals2/example/doc_view_acm.cpp

   1 // Document/View sample for Boost.Signals2.
   2 // Expands on doc_view.cpp example by using automatic
   3 // connection management.
   4 //
   5 // Copyright Keith MacDonald 2005.
   6 // Copyright Frank Mori Hess 2009.
   7 //
   8 // Use, modification and
   9 // distribution is subject to the Boost Software License, Version
  10 // 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  11 // http://www.boost.org/LICENSE_1_0.txt)
  12 // For more information, see http://www.boost.org
  13
  14 #include <iostream>
  15 #include <string>
  16 #include <boost/bind.hpp>
  17 #include <boost/io/ios_state.hpp>
  18 #include <boost/signals2/signal.hpp>
  19 #include <boost/shared_ptr.hpp>
  20
  21 class Document
  22 {
  23 public:
  24   typedef boost::signals2::signal<void ()>  signal_t;
  25
  26 public:
  27   Document()
  28   {}
  29
  30   /* connect a slot to the signal which will be emitted whenever
  31     text is appended to the document. */
  32   boost::signals2::connection connect(const signal_t::slot_type &subscriber)
  33   {
  34     return m_sig.connect(subscriber);
  35   }
  36
  37   void append(const char* s)
  38   {
  39     m_text += s;
  40     m_sig();
  41   }
  42
  43   const std::string& getText() const
  44   {
  45     return m_text;
  46   }
  47
  48 private:
  49   signal_t    m_sig;
  50   std::string m_text;
  51 };
  52
  53 class TextView
  54 {
  55 public:
  56   // static factory function that sets up automatic connection tracking
  57   static boost::shared_ptr<TextView> create(Document& doc)
  58   {
  59     boost::shared_ptr<TextView> new_view(new TextView(doc));
  60     {
  61       typedef Document::signal_t::slot_type slot_type;
  62       slot_type myslot(&TextView::refresh, new_view.get());
  63       doc.connect(myslot.track(new_view));
  64     }
  65     return new_view;
  66   }
  67
  68   void refresh() const
  69   {
  70     std::cout << "TextView: " << m_document.getText() << std::endl;
  71   }
  72 private:
  73     // private constructor to force use of static factory function
  74     TextView(Document &doc): m_document(doc)
  75     {}
  76
  77     Document&               m_document;
  78 };
  79
  80 class HexView
  81 {
  82 public:
  83   // static factory function that sets up automatic connection tracking
  84   static boost::shared_ptr<HexView> create(Document& doc)
  85   {
  86     boost::shared_ptr<HexView> new_view(new HexView(doc));
  87     {
  88       typedef Document::signal_t::slot_type slot_type;
  89       slot_type myslot(&HexView::refresh, new_view.get());
  90       doc.connect(myslot.track(new_view));
  91     }
  92     return new_view;
  93   }
  94
  95   void refresh() const
  96   {
  97     boost::io::ios_flags_saver ifs(std::cout);
  98     const std::string&  s = m_document.getText();
  99
 100     std::cout << "HexView:";
 101
 102     for (std::string::const_iterator it = s.begin(); it != s.end(); ++it)
 103       std::cout << ' ' << std::hex << static_cast<int>(*it);
 104
 105     std::cout << std::endl;
 106   }
 107 private:
 108   // private constructor to force use of static factory function
 109   HexView(Document& doc): m_document(doc)
 110   {}
 111
 112   Document&               m_document;
 113 };
 114
 115 int main(int argc, char* argv[])
 116 {
 117   Document    doc;
 118   boost::shared_ptr<TextView> v1 = TextView::create(doc);
 119   boost::shared_ptr<HexView> v2 = HexView::create(doc);
 120
 121   doc.append(argc >= 2 ? argv[1] : "Hello world!");
 122
 123   v2.reset(); // destroy the HexView, automatically disconnecting
 124   doc.append("  HexView should no longer be connected.");
 125
 126   return 0;
 127 }