Scrolling layout

WidgetsNew/private/layouts/ScrollableLayout.cpp

@@ -0,0 +1,53 @@
+#include "ScrollableLayout.hpp"
+
+// fixme : this dependency should be removed
+#include "ScrollableWidget.hpp"
+
+using namespace tp;
+
+void ScrollableLayout::updateLayout(bool vertical) {
+	if (vertical) return;
+
+	// TODO : make better interface to get scroller and content widget
+	if (children().size() != 2) return;
+
+	auto scroller = dynamic_cast<ScrollableBarWidget*>(children().front());
+	auto content = children().back();
+
+	if (!scroller || !content) return;
+
+	updateWidgetRects(getArea(), content, scroller);
+}
+
+void ScrollableLayout::updateWidgetRects(const RectF& area, Widget* content, ScrollableBarWidget* scroller) const {
+	bool dir = scroller->getDirection();
+
+	// update content
+	// auto contentItems = content->getLayout()->getChildrenEnclosure();
+	// content->getLayout()->setArea(contentItems.shrinkFromCenter(-10, true));
+	content->getLayout()->pickRect(dir);
+
+	auto sizeFactor = (area.size[dir] / content->getLayout()->getArea().size[dir]);
+	auto splitFactor = 1 - ((sizeFactor > 1.f) ?  0 : mScrollerSize / area.size[!dir]);
+
+	auto holderArea = area.splitByFactorHL(splitFactor);
+	auto contentArea = content->getLayout()->getArea();
+	auto scrollerArea = area.splitByFactorHR(splitFactor);
+
+	scroller->updateSizeFactor(sizeFactor);
+
+	contentArea.pos[dir] = -scroller->getPosFactor() * contentArea.size[dir];
+	contentArea.size[!dir] = holderArea.size[!dir];
+	contentArea.pos[!dir] = 0;
+
+	scroller->getLayout()->setArea(scrollerArea);
+	content->getLayout()->setArea(contentArea);
+}
+
+RectF ScrollableLayout::getAvailableChildArea() const {
+	auto out = getArea();
+	// dont constrain on scroll axis
+	out.pos = -FLT_MAX / 4;
+	out.size = FLT_MAX / 2;
+	return out;
+}