chart2/source/inc/WeakListenerAdapter.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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  18  */
  19 #pragma once
  20
  21 #include <com/sun/star/lang/XEventListener.hpp>
  22 #include <com/sun/star/view/XSelectionChangeListener.hpp>
  23 #include <cppuhelper/weakref.hxx>
  24 #include <cppuhelper/implbase.hxx>
  25
  26 namespace chart
  27 {
  28
  29 /** Adapter that enables adding listeners as weak UNO references.  Thus, adding
  30     an object as listener to a broadcaster does not increase its reference
  31     count.
  32
  33     <p>The helper class, of course, is held as hard reference at the
  34     broadcaster, but this should never be a problem as the adapter's life time
  35     depends on no other object.</p>
  36
  37     <p>Note that in order to remove an object as listener, you have to remove
  38     the same wrapper that you added, i.e., you should store the adapter as a
  39     member in the adapted class for later use.</p>
  40  */
  41 class WeakSelectionChangeListenerAdapter final :
  42         public ::cppu::WeakImplHelper< css::view::XSelectionChangeListener >
  43 {
  44 public:
  45     explicit WeakSelectionChangeListenerAdapter(
  46         const css::uno::Reference< css::view::XSelectionChangeListener > & xListener )
  47             : m_xListener( xListener ) {}
  48     virtual ~WeakSelectionChangeListenerAdapter() override;
  49
  50 protected:
  51     // ____ XSelectionChangeListener ____
  52     virtual void SAL_CALL selectionChanged(
  53         const css::lang::EventObject& aEvent ) override;
  54
  55     // ____ XEventListener (base of all listeners) ____
  56     virtual void SAL_CALL disposing(
  57         const css::lang::EventObject& Source ) override
  58     {
  59         css::uno::Reference< css::view::XSelectionChangeListener > xEventListener( m_xListener );
  60         if( xEventListener.is())
  61             xEventListener->disposing( Source );
  62     }
  63
  64 private:
  65     css::uno::WeakReference< css::view::XSelectionChangeListener > m_xListener;
  66 };
  67
  68 } //  namespace chart
  69
  70 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */