lyx_mirror/src/insets/render_preview.h
Angus Leeming 1c4ae33f9a A little further clean-up.
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@7895 a592a061-630c-0410-9148-cb99ea01b6c8
2003-10-10 21:24:06 +00:00

122 lines
3.1 KiB
C++

// -*- C++ -*-
/**
* \file render_preview.h
* This file is part of LyX, the document processor.
* Licence details can be found in the file COPYING.
*
* \author Angus Leeming
*
* Full author contact details are available in file CREDITS.
*
* lyx::graphics::RenderPreview is an abstract base class that can help
* insets to generate previews. The daughter class must instantiate two small
* methods. The Inset would own an instance of this daughter class.
*/
#ifndef RENDER_PREVIEW_H
#define RENDER_PREVIEW_H
#include "render_base.h"
#include "support/FileMonitor.h"
#include <boost/signals/signal0.hpp>
#include <boost/signals/trackable.hpp>
#include <boost/signals/connection.hpp>
class Buffer;
class BufferView;
class MetricsInfo;
class PainterInfo;
namespace lyx {
namespace graphics {
class PreviewImage;
class PreviewLoader;
} // namespace graphics
} // namespace lyx
class RenderPreview : public RenderBase, public boost::signals::trackable {
public:
/// a wrapper for Previews::activated()
static bool activated();
RenderPreview();
RenderPreview(RenderPreview const &);
RenderBase * clone() const;
/// Compute the size of the object, returned in dim
void metrics(MetricsInfo &, Dimension & dim) const;
///
void draw(PainterInfo & pi, int x, int y) const;
/** Find the PreviewLoader, add a LaTeX snippet to it and
* start the loading process.
*/
void generatePreview(std::string const & latex_snippet,
Buffer const &);
/** Add a LaTeX snippet to the PreviewLoader but do not start the
* loading process.
*/
void addPreview(std::string const & latex_snippet,
lyx::graphics::PreviewLoader & ploader);
/** Remove a snippet from the cache of previews.
* Useful if previewing the contents of a file that has changed.
*/
void removePreview(Buffer const &);
/// The preview has been generated and is ready to use.
bool previewReady() const;
/// Connect and you'll be informed when the preview is ready.
typedef boost::signal0<void>::slot_type slot_type;
boost::signals::connection connect(slot_type const &);
private:
/// Not implemented.
void operator=(RenderPreview const &);
/// This method is connected to the PreviewLoader::imageReady signal.
void imageReady(lyx::graphics::PreviewImage const &);
/// The thing that we're trying to generate a preview of.
std::string snippet_;
/// We don't own this. Cached for efficiency reasons.
lyx::graphics::PreviewImage const * pimage_;
/** Store the connection to the preview loader so that we connect
* only once.
*/
boost::signals::connection ploader_connection_;
/// This signal is emitted when the preview is ready for display.
boost::signal0<void> preview_ready_signal_;
};
class RenderMonitoredPreview : public RenderPreview {
public:
RenderMonitoredPreview() : monitor_(std::string(), 2000) {}
///
bool monitoring() const { return monitor_.monitoring(); }
///
void startMonitoring(std::string const & file);
///
void stopMonitoring() { monitor_.stop(); }
/// Connect and you'll be informed when the file changes.
boost::signals::connection fileChanged(slot_type const &);
private:
///
lyx::support::FileMonitor monitor_;
};
#endif // RENDERPREVIEW_H