47 lines
		
	
	
	
		
			1.4 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			47 lines
		
	
	
	
		
			1.4 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
/*
 | 
						|
This file is part of Telegram Desktop,
 | 
						|
the official desktop application for the Telegram messaging service.
 | 
						|
 | 
						|
For license and copyright information please follow this link:
 | 
						|
https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 | 
						|
*/
 | 
						|
#include "ui/effects/scroll_content_shadow.h"
 | 
						|
 | 
						|
#include "ui/rp_widget.h"
 | 
						|
#include "ui/widgets/scroll_area.h"
 | 
						|
#include "ui/wrap/fade_wrap.h"
 | 
						|
 | 
						|
namespace Ui {
 | 
						|
 | 
						|
void SetupShadowsToScrollContent(
 | 
						|
		not_null<Ui::RpWidget*> parent,
 | 
						|
		not_null<Ui::ScrollArea*> scroll,
 | 
						|
		rpl::producer<int> &&innerHeightValue) {
 | 
						|
	using namespace rpl::mappers;
 | 
						|
 | 
						|
	const auto topShadow = Ui::CreateChild<Ui::FadeShadow>(parent.get());
 | 
						|
	const auto bottomShadow = Ui::CreateChild<Ui::FadeShadow>(parent.get());
 | 
						|
	scroll->geometryValue(
 | 
						|
	) | rpl::start_with_next_done([=](const QRect &geometry) {
 | 
						|
		topShadow->resizeToWidth(geometry.width());
 | 
						|
		topShadow->move(
 | 
						|
			geometry.x(),
 | 
						|
			geometry.y());
 | 
						|
		bottomShadow->resizeToWidth(geometry.width());
 | 
						|
		bottomShadow->move(
 | 
						|
			geometry.x(),
 | 
						|
			geometry.y() + geometry.height() - st::lineWidth);
 | 
						|
	}, [t = Ui::MakeWeak(topShadow), b = Ui::MakeWeak(bottomShadow)] {
 | 
						|
		Ui::DestroyChild(t.data());
 | 
						|
		Ui::DestroyChild(b.data());
 | 
						|
	}, topShadow->lifetime());
 | 
						|
 | 
						|
	topShadow->toggleOn(scroll->scrollTopValue() | rpl::map(_1 > 0));
 | 
						|
	bottomShadow->toggleOn(rpl::combine(
 | 
						|
		scroll->scrollTopValue(),
 | 
						|
		scroll->heightValue(),
 | 
						|
		std::move(innerHeightValue),
 | 
						|
		_1 + _2 < _3));
 | 
						|
}
 | 
						|
 | 
						|
} // namespace Ui
 |