Properly track the lifetime of signals2::slots (#8261)

[lyx.git] / src / graphics / GraphicsCacheItem.cpp

diff --git a/src/graphics/GraphicsCacheItem.cpp b/src/graphics/GraphicsCacheItem.cpp
index 4ed496a533d52d671b983e74a900e8891f219e05..576ad92bc7a8e734dcb017609ca2be0b9c7993c1 100644 (file)
--- a/src/graphics/GraphicsCacheItem.cpp
+++ b/src/graphics/GraphicsCacheItem.cpp
@@ -29,7 +29,6 @@
 #include "support/lassert.h"
 #include "support/unique_ptr.h"
 
-#include "support/bind.h"
 #include "support/TempFile.h"
 
 using namespace std;
@@ -39,7 +38,7 @@ namespace lyx {
 
 namespace graphics {
 
-class CacheItem::Impl : public boost::signals2::trackable {
+class CacheItem::Impl {
 public:
 
        ///
@@ -50,7 +49,7 @@ public:
        /**
         *  If no file conversion is needed, then tryDisplayFormat() calls
         *  loadImage() directly.
-        * \return true if a conversion is necessary and no error occurred. 
+        * \return true if a conversion is necessary and no error occurred.
         */
        bool tryDisplayFormat(FileName & filename, string & from);
 
@@ -97,7 +96,7 @@ public:
        /// The filename we refer too.
        FileName const filename_;
        /// The document filename this graphic item belongs to
-       FileName const & doc_file_;
+       FileName const doc_file_;
        ///
        ActiveFileMonitorPtr monitor_;
 
@@ -120,10 +119,7 @@ public:
        ImageStatus status_;
 
        /// This signal is emitted when the image loading status changes.
-       boost::signals2::signal<void()> statusChanged;
-
-       /// The connection of the signal ConvProcess::finishedConversion,
-       boost::signals2::connection cc_;
+       signals2::signal<void()> statusChanged;
 
        ///
        unique_ptr<Converter> converter_;
@@ -199,7 +195,7 @@ ImageStatus CacheItem::status() const
 }
 
 
-boost::signals2::connection CacheItem::connect(slot_type const & slot) const
+signals2::connection CacheItem::connect(slot_type const & slot) const
 {
        return pimpl_->statusChanged.connect(slot);
 }
@@ -223,6 +219,7 @@ void CacheItem::Impl::startMonitor()
        if (monitor_)
                return;
        monitor_ = FileSystemWatcher::activeMonitor(filename_);
+       // Disconnected at the same time as this is destroyed.
        monitor_->connect([=](){ startLoading(); });
 }
 
@@ -254,9 +251,6 @@ void CacheItem::Impl::reset()
 
        status_ = WaitingToLoad;
 
-       if (cc_.connected())
-               cc_.disconnect();
-
        if (converter_)
                converter_.reset();
 }
@@ -280,7 +274,6 @@ void CacheItem::Impl::imageConverted(bool success)
        file_to_load_ = converter_ ? FileName(converter_->convertedFile())
                                       : FileName();
        converter_.reset();
-       cc_.disconnect();
 
        success = !file_to_load_.empty() && file_to_load_.isReadableFile();
 
@@ -449,9 +442,13 @@ void CacheItem::Impl::convertToDisplayFormat()
        // Connect a signal to this->imageConverted and pass this signal to
        // the graphics converter so that we can load the modified file
        // on completion of the conversion process.
-       converter_ = make_unique<Converter>(doc_file_, filename, to_file_base.absFileName(),
+       converter_ = make_unique<Converter>(doc_file_, filename,
+                                           to_file_base.absFileName(),
                                            from, to_);
-       converter_->connect(bind(&Impl::imageConverted, this, _1));
+       // Connection is closed at the same time as *this is destroyed.
+       converter_->connect([this](bool success){
+                       imageConverted(success);
+               });
        converter_->startConversion();
 }