Fixed a ListView dangling pointer bug

.clangd

@@ -1,4 +1,5 @@
 CompileFlags:
     CompilationDatabase: bin
+    Add: ["--target=x86_64-w64-mingw32"]
 Diagnostics:
     MissingIncludes: None

src/ogfx/gui/widgets/ListView.cpp

@@ -35,6 +35,7 @@ namespace ogfx
 					return;
 				m_text = text;
 				update_dimensions();
+				if (m_parent) m_parent->m_extentsDirty = true;
 			}
 
 			void ListView::Item::setFontSize(i32 fontSize)
@@ -43,6 +44,7 @@ namespace ogfx
 					return;
 				m_fontSize = fontSize;
 				update_dimensions();
+				if (m_parent) m_parent->m_extentsDirty = true;
 			}
 
 			void ListView::Item::update_dimensions(void)
@@ -108,35 +110,31 @@ namespace ogfx
 
 			void ListView::onDraw(ogfx::BasicRenderer2D& gfx)
 			{
-				// f32 y = 0;
 				const auto& bounds = getGlobalBounds();
 				const auto& content = getContentExtents();
-				Color textColor;
+				const f32 scrollY = -getScrollOffset().y;
-				// Compute the visible Y window in content space
-				const f32 scrollY      = -getScrollOffset().y;           // positive offset into content
 				const f32 visibleH = getContentBounds().h;
 				const f32 visibleStart = scrollY;
 				const f32 visibleEnd  = scrollY + visibleH;
+				Color textColor;
 
-				// Find the starting item and its Y via a linear scan...
 				f32 y = 0;
 				i32 startIdx = 0;
 				for (auto& item : m_list)
 				{
 					if (!item.isValid()) { startIdx++; continue; }
 					f32 itemH = item.getDimensions().y;
-					if (y + itemH > visibleStart) break;   // this item is the first one in view
+					if (y + itemH > visibleStart) break;
 					y += itemH;
 					startIdx++;
 				}
 
-				// ...then process only items from startIdx until we exceed visibleEnd
 				for (i32 i = startIdx; i < (i32)m_list.size(); i++)
 				{
 					auto& item = m_list[i];
 					if (!item.isValid()) continue;
 					f32 itemH = item.getDimensions().y;
-					if (y > visibleEnd) break;             // past the visible window, stop
+					if (y > visibleEnd) break;
 					if (item.isSelected())
 					{
 						textColor = item.getSelectedTextColor();
@@ -146,24 +144,8 @@ namespace ogfx
 						textColor = item.getTextColor();
 					gfx.drawLine({ Vec2 { bounds.x, bounds.y + y + itemH + 4 } + getScrollOffset(), Vec2 { bounds.x + content.w, bounds.y + y + itemH + 4 } + getScrollOffset() }, Colors::Black, 1);
 					gfx.drawString(item, bounds.getPosition() + Vec2 { 0, y } + getScrollOffset() + item.getPadding().getPosition(), textColor, item.getFontSize());
-					// draw or hit-test item at content Y = y
 					y += itemH;
 				}
-				// for (auto& item : m_list)
-				// {
-				//     if (!item.isValid()) continue;
-				//     const auto& size = item.getDimensions();
-				//     if (item.isSelected())
-				//     {
-				//         textColor = item.getSelectedTextColor();
-				//         gfx.fillRect({ Vec2 { bounds.x, bounds.y + y + 4 } + getScrollOffset(), { content.w, size.y } }, item.getSelectedColor());
-				//     }
-				//     else
-				//         textColor = item.getTextColor();
-				//     gfx.drawLine({ Vec2 { bounds.x, bounds.y + y + size.y + 4 } + getScrollOffset(), Vec2 { bounds.x + content.w, bounds.y + y + size.y + 4 } + getScrollOffset() }, Colors::Black, 1);
-				//     gfx.drawString(item, bounds.getPosition() + Vec2 { 0, y } + getScrollOffset() + item.getPadding().getPosition(), textColor, item.getFontSize());
-				//     y += size.y;
-				// }
 			}
 
 			void ListView::afterDraw(ogfx::BasicRenderer2D& gfx)
@@ -188,10 +170,11 @@ namespace ogfx
 				{
 					if (!item.isValid()) continue;
 					const f32 itemH = item.getDimensions().y;
-					if (!item.isSelected() && localY >= y && localY < y + itemH)
+					if (localY >= y && localY < y + itemH)
 					{
+						bool wasSelected = item.isSelected();
 						item.set_selected(m_selectedList);
-						if (callback_onSelectionChanged)
+						if (!wasSelected && callback_onSelectionChanged)
 							callback_onSelectionChanged(m_selectedList);
 						event.handle();
 						break;
@@ -202,6 +185,9 @@ namespace ogfx
 
 			Rectangle ListView::getContentExtents(void) const
 			{
+
+				if (!m_extentsDirty)
+					return m_cachedExtents;
 				f32 maxX = 0, maxY = 0;
 				for (auto& item : m_list)
 				{
@@ -210,10 +196,12 @@ namespace ogfx
 					maxX = std::max(maxX, size.x);
 					maxY += size.y;
 				}
-				return { 0, 0, maxX, maxY };
+				m_cachedExtents = { 0, 0, maxX, maxY };
+				m_extentsDirty = false;
+				return m_cachedExtents;
 			}
 
-			ListView::Item& ListView::getItem(const String& text)
+			ListView::Item& ListView::getLine(const String& text)
 			{
 				for (auto& item : m_list)
 					if (item.getText() == text)
@@ -221,7 +209,7 @@ namespace ogfx
 				return InvalidItem;
 			}
 
-			ListView::Item& ListView::getItem(u32 index)
+			ListView::Item& ListView::getLine(u32 index)
 			{
 				if (index < m_list.size())
 					return m_list[index];
@@ -238,10 +226,31 @@ namespace ogfx
 				item.setSelectedTextColor(m_defaultSelectionTextColor);
 				item.setText(text);
 				m_list.push_back(item);
-				if (m_list.size() == 1)
+				if (m_list.size() > 0)
-					m_list.back().set_selected(m_selectedList);
+					m_list[0].set_selected(m_selectedList);
+				m_extentsDirty = true;
 				return m_list.back();
 			}
+
+			bool ListView::removeLine(const String& text)
+			{
+				return false; //TODO: Implement
+			}
+
+			bool ListView::removeLine(u32 index)
+			{
+				return false; //TODO: Implement
+			}
+
+			bool ListView::hasLine(const String& text)
+			{
+				return false; //TODO: Implement
+			}
+
+			bool ListView::hasLine(u32 index)
+			{
+				return false; //TODO: Implement
+			}
 		}
 	}
 }

src/ogfx/gui/widgets/ListView.hpp

@@ -22,6 +22,7 @@
 
 #include <ogfx/gui/widgets/Widget.hpp>
 #include <ogfx/gui/widgets/Scrollbar.hpp>
+#include <deque>
 
 namespace ogfx
 {
@@ -78,9 +79,13 @@ namespace ogfx
 					void afterDraw(ogfx::BasicRenderer2D& gfx) override;
 					void onMouseReleased(const Event& event) override;
 					Rectangle getContentExtents(void) const override;
-					Item& getItem(const String& text);
+					Item& getLine(const String& text);
-					Item& getItem(u32 index);
+					Item& getLine(u32 index);
 					Item& addLine(const String& text);
+					bool removeLine(const String& text);
+					bool removeLine(u32 index);
+					bool hasLine(const String& text);
+					bool hasLine(u32 index);
 					inline void addLine(const Item& line) { m_list.push_back(line); if (m_list.size() == 1) m_list.back().set_selected(m_selectedList); }
 					inline stdvec<Item*>& getSelection(void) { return m_selectedList; }
 					inline void setSelectionChangedCallback(std::function<void(stdvec<Item*>& selection)> callback) { callback_onSelectionChanged = std::move(callback); }
@@ -95,9 +100,12 @@ namespace ogfx
 
 				private:
 					Item InvalidItem { *this };
-					stdvec<Item> m_list;
+					std::deque<Item> m_list;
 					stdvec<Item*> m_selectedList;
 					std::function<void(stdvec<Item*>& selection)> callback_onSelectionChanged { nullptr };
+					mutable Rectangle m_cachedExtents { 0, 0, 0, 0 };
+					mutable bool m_extentsDirty { true };
+
 					Color m_lineColor { 40, 40, 40 };
 					bool m_showLine { true };
 					i32 m_defaultLinefontSize { 16 };

src/ogfx/gui/widgets/Slider.cpp

@@ -74,6 +74,28 @@ namespace ogfx
 				set_value(mouse_position_to_value({ event.mouse->position_x, event.mouse->position_y }));
 			}
 
+			void Slider::onMouseScrolled(const Event& event)
+			{
+				if (!isMouseInside())
+					return;
+				if (!isScrollWheelShortcutEnabled())
+					return;
+				if (getStep() > 0)
+				{
+					if (event.mouse->scroll == MouseEventData::eScrollDirection::Down ||
+						event.mouse->scroll == MouseEventData::eScrollDirection::Right)
+						set_value(getValue() + (getStep() * -1));
+					else
+						set_value(getValue() + getStep());
+				}
+				else if (event.mouse->scroll == MouseEventData::eScrollDirection::Down ||
+						 event.mouse->scroll == MouseEventData::eScrollDirection::Up)
+					set_value(getValue() + (0.1f * event.mouse->scrollAmount.y));
+				else
+					set_value(getValue() + (0.1f * event.mouse->scrollAmount.x));
+				event.handle();
+			}
+
 			void Slider::onDraw(ogfx::BasicRenderer2D& gfx)
 			{
 				const auto& bounds = getGlobalContentBounds();
@@ -143,7 +165,7 @@ namespace ogfx
 
 			f32 Slider::snap_to_step(f32 val)
 			{
-				if (m_step <= 0.0f) return val; // full precision
+				if (m_step <= 0.0f) return std::clamp(val, m_min, m_max); // full precision
 				f32 snapped = std::round((val - m_min) / m_step) * m_step + m_min;
 				return std::clamp(snapped, m_min, m_max);
 			}

src/ogfx/gui/widgets/Slider.hpp

@@ -36,6 +36,7 @@ namespace ogfx
 					void applyTheme(const ostd::Stylesheet& theme) override;
 					void onMouseReleased(const Event& event) override;
 					void onMouseDragged(const Event& event) override;
+					void onMouseScrolled(const Event& event) override;
 					void onDraw(ogfx::BasicRenderer2D& gfx) override;
 					inline f32 getValue(void) const { return m_value; }
 					inline void setValueChangedCallback(std::function<void(f32 oldValue, f32 newValue)> callback) { callback_onValueChanged = std::move(callback); }
@@ -48,6 +49,7 @@ namespace ogfx
 					inline void disableHorizontal(void) { enableHorizontal(false); }
 
 					OSTD_BOOL_PARAM_GETSET_E(MiddleClickShortcut, m_middleClickShortcut);
+					OSTD_BOOL_PARAM_GETSET_E(ScrollWheelShortcut, m_enableScrollWheel);
 					OSTD_PARAM_GETSET(f32, MinValue, m_min);
 					OSTD_PARAM_GETSET(f32, MaxValue, m_max);
 					OSTD_PARAM_GETSET(f32, Step, m_step);
@@ -75,6 +77,7 @@ namespace ogfx
 					f32 m_step { 0.1f };
 					bool m_vertical { false };
 					bool m_middleClickShortcut { true };
+					bool m_enableScrollWheel { true };
 
 					f32 m_trackWidth { 6 };
 					Color m_trackColor { "#500000FF" };

src/test/GuiTest.cpp

@@ -119,12 +119,12 @@ class Window : public ogfx::gui::Window
 
 			m_list.setSize(200, 300);
 
-			for (i32 i = 0; i < 100; i++)
+			for (i32 i = 0; i < 10000; i++)
 			{
-				m_list.addLine(ostd::Random::getString(ostd::Random::getui8(0, 40)));
+				m_list.addLine(ostd::Random::getString(ostd::Random::getui8(1, 40)));
 			}
-			m_list.getItem(10).setFontSize(40);
+			m_list.getLine(10).setFontSize(40);
-			m_list.getItem(160).setTextColor(Colors::Crimson);
+			m_list.getLine(160).setTextColor(Colors::Crimson);
 			m_list.setSelectionChangedCallback([&](stdvec<ogfx::gui::widgets::ListView::Item*>& selection) -> void {\
 				std::cout << *(selection[0]) << "\n";
 			});