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