kicad/include/widgets/busy_indicator.h

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2.1 KiB
C++

/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2019 KiCad Developers, see AUTHORS.TXT for contributors.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#ifndef COMMON_WIDGETS_BUSY_INDICATOR__H
#define COMMON_WIDGETS_BUSY_INDICATOR__H
#include <functional>
#include <memory>
/**
* A class that can be used to implement a "busy" indicator. The exact form
* of the busy indicator is unspecified. It could be a "spinner" cursor in a GUI
* context, for example.
*
* This base class provides a "null" implementation, and can be overridden for
* specific behaviours.
*
* THe busy-ness semantics are defined by this object's lifetime.
*/
class BUSY_INDICATOR
{
public:
/**
* A factory function that returns a new busy indicator.
*
* Because BUSY_INDICATORs are RAII objects (i.e. the busy-ness is defined
* by the object's lieftime), it's convenient to pass a factory function for
* a client to be able to make a busy indicator when needed.
*/
using FACTORY = std::function<std::unique_ptr<BUSY_INDICATOR>()>;
/**
* This class is intended to be handled by pointer-to-base class
*/
virtual ~BUSY_INDICATOR() = default;
};
#endif // COMMON_WIDGETS_BUSY_INDICATOR__H