src/graphics/PreviewedInset.C

   1 /**
   2  * \file PreviewedInset.C
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Angus Leeming
   7  *
   8  * Full author contact details are available in file CREDITS.
   9  */
  10
  11 #include <config.h>
  12
  13 #include "PreviewedInset.h"
  14 #include "GraphicsImage.h"
  15 #include "PreviewLoader.h"
  16 #include "PreviewImage.h"
  17 #include "Previews.h"
  18
  19 #include "buffer.h"
  20 #include "BufferView.h"
  21
  22 #include "frontends/LyXView.h"
  23
  24 #include "support/lstrings.h"
  25
  26 #include <boost/bind.hpp>
  27
  28 namespace support = lyx::support;
  29
  30
  31 namespace lyx {
  32 namespace graphics {
  33
  34 bool PreviewedInset::activated()
  35 {
  36         return Previews::activated();
  37 }
  38
  39
  40 BufferView * PreviewedInset::view() const
  41 {
  42         return inset_.view();
  43 }
  44
  45
  46 void PreviewedInset::generatePreview()
  47 {
  48         if (!Previews::activated() || !previewWanted() ||
  49             !view() || !view()->buffer())
  50                 return;
  51
  52         Previews & previews = Previews::get();
  53         PreviewLoader & loader = previews.loader(*view()->buffer());
  54         addPreview(loader);
  55         if (!snippet_.empty())
  56                 loader.startLoading();
  57 }
  58
  59
  60 void PreviewedInset::addPreview(PreviewLoader & ploader)
  61 {
  62         if (!Previews::activated() || !previewWanted())
  63                 return;
  64
  65         snippet_ = support::trim(latexString());
  66         if (snippet_.empty())
  67                 return;
  68
  69         pimage_ = ploader.preview(snippet_);
  70         if (pimage_)
  71                 return;
  72
  73         // If this is the first time of calling, connect to the
  74         // PreviewLoader signal that'll inform us when the preview image
  75         // is ready for loading.
  76         if (!connection_.connected()) {
  77                 connection_ = ploader.connect(
  78                         boost::bind(&PreviewedInset::imageReady, this, _1));
  79         }
  80
  81         ploader.add(snippet_);
  82 }
  83
  84
  85 void PreviewedInset::removePreview()
  86 {
  87         if (!view() || !view()->buffer() || snippet_.empty())
  88                 return;
  89
  90         Previews & previews = Previews::get();
  91         PreviewLoader & loader = previews.loader(*view()->buffer());
  92         loader.remove(snippet_);
  93         snippet_.erase();
  94         pimage_ = 0;
  95 }
  96
  97
  98 bool PreviewedInset::previewReady() const
  99 {
 100         if (!Previews::activated() || !previewWanted() ||
 101             !view() || !view()->buffer())
 102                 return false;
 103
 104         if (!pimage_ || snippet_ != pimage_->snippet()) {
 105                 PreviewLoader & ploader =
 106                         Previews::get().loader(*view()->buffer());
 107                 pimage_ = ploader.preview(snippet_);
 108         }
 109
 110         if (!pimage_)
 111                 return false;
 112
 113         return pimage_->image();
 114 }
 115
 116
 117 void PreviewedInset::imageReady(PreviewImage const & pimage) const
 118 {
 119         // Check snippet against the Inset's current contents
 120         if (snippet_ != pimage.snippet())
 121                 return;
 122
 123         pimage_ = &pimage;
 124
 125         if (view())
 126                 view()->updateInset(inset());
 127 }
 128
 129 } // namespace graphics
 130 } // namespace lyx