tdesktop/Telegram/SourceFiles/ui/effects/fade_animation.h

/*
This file is part of Telegram Desktop,
the official desktop version of Telegram messaging app, see https://telegram.org

Telegram Desktop 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 3 of the License, or
(at your option) any later version.

It 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.

In addition, as a special exception, the copyright holders give permission
to link the code of portions of this program with the OpenSSL library.

Full license: https://github.com/telegramdesktop/tdesktop/blob/master/LICENSE
Copyright (c) 2014-2017 John Preston, https://desktop.telegram.org
*/
#pragma once

#include "styles/style_widgets.h"
#include "ui/rp_widget.h"

namespace Ui {

class FadeAnimation {
public:
	FadeAnimation(TWidget *widget, bool scaled = false);

	bool paint(Painter &p);
	void refreshCache();

	using FinishedCallback = base::lambda<void()>;
	void setFinishedCallback(FinishedCallback &&callback);

	using UpdatedCallback = base::lambda<void(float64)>;
	void setUpdatedCallback(UpdatedCallback &&callback);

	void show();
	void hide();

	void fadeIn(int duration);
	void fadeOut(int duration);

	void finish() {
		stopAnimation();
	}

	bool animating() const {
		return _animation.animating();
	}
	bool visible() const {
		return _visible;
	}

private:
	void startAnimation(int duration);
	void stopAnimation();

	void updateCallback();
	QPixmap grabContent();

	TWidget *_widget = nullptr;
	bool _scaled = false;

	Animation _animation;
	QSize _size;
	QPixmap _cache;
	bool _visible = false;

	FinishedCallback _finishedCallback;
	UpdatedCallback _updatedCallback;

};

} // namespace Ui