add an explicit Cancel handler

cui/source/dialogs/about.cxx

@@ -163,6 +163,8 @@ AboutDialog::AboutDialog( Window* pParent, const ResId& rId) :
     aFeaturesLink.SetBackground();
     aFeaturesLink.SetClickHdl( LINK( this, AboutDialog, HandleHyperlink ) );
 
+    aCancelButton.SetClickHdl( LINK( this, AboutDialog, CancelHdl ) );
+
     Color aTextColor( rSettings.GetWindowTextColor() );
     aVersionText.SetControlForeground( aTextColor );
     aCopyrightText.SetControlForeground( aTextColor );
@@ -288,6 +290,13 @@ AboutDialog::AboutDialog( Window* pParent, const ResId& rId) :
     SetHelpId( CMD_SID_ABOUT );
 }
 
+//-----------------------------------------------------------------------
+IMPL_LINK_NOARG(AboutDialog, CancelHdl)
+{
+    Close();
+    return 0;
+}
+
 // -----------------------------------------------------------------------
 
 IMPL_LINK( AboutDialog, HandleHyperlink, svt::FixedHyperlink*, pHyperlink )

cui/source/inc/about.hxx

@@ -72,7 +72,8 @@ protected:
 public:
     AboutDialog( Window* pParent, const ResId& rId);
 
-    DECL_LINK( HandleHyperlink, svt::FixedHyperlink * );
+    DECL_LINK(CancelHdl, void *);
+    DECL_LINK(HandleHyperlink, svt::FixedHyperlink *);
 };
 
 #endif // #ifndef _ABOUT_HXX