Make UI events const refs and celan up redundant use of virtual with override.event_cleanup

68 files changed, 263 insertions, 262 deletions

diff --git a/dggui/button.cc b/dggui/button.cc
index 39e9eaa..c673ab1 100644
--- a/dggui/button.cc
+++ b/dggui/button.cc
@@ -43,7 +43,7 @@ Button::~Button()
 {
 }
 
-void Button::repaintEvent(RepaintEvent* repaintEvent)
+void Button::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 	p.clear();
diff --git a/dggui/button.h b/dggui/button.h
index f1b6584..56c7aaa 100644
--- a/dggui/button.h
+++ b/dggui/button.h
@@ -41,7 +41,7 @@ public:
 
 protected:
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* e) override;
+	void repaintEvent(const RepaintEvent& event) override;
 
 private:
 	TexturedBox box_up{getImageCache(), ":resources/pushbutton.png",
diff --git a/dggui/button_base.cc b/dggui/button_base.cc
index 4625b55..0cd7186 100644
--- a/dggui/button_base.cc
+++ b/dggui/button_base.cc
@@ -40,15 +40,15 @@ ButtonBase::~ButtonBase()
 {
 }
 
-void ButtonBase::buttonEvent(ButtonEvent* buttonEvent)
+void ButtonBase::buttonEvent(const ButtonEvent& buttonEvent)
 {
 	// Ignore everything except left clicks.
-	if(!enabled || buttonEvent->button != MouseButton::left)
+	if(!enabled || buttonEvent.button != MouseButton::left)
 	{
 		return;
 	}
 
-	if(buttonEvent->direction == Direction::down)
+	if(buttonEvent.direction == Direction::down)
 	{
 		draw_state = State::Down;
 		button_state = State::Down;
@@ -56,7 +56,7 @@ void ButtonBase::buttonEvent(ButtonEvent* buttonEvent)
 		redraw();
 	}
 
-	if(buttonEvent->direction == Direction::up)
+	if(buttonEvent.direction == Direction::up)
 	{
 		draw_state = State::Up;
 		button_state = State::Up;
diff --git a/dggui/button_base.h b/dggui/button_base.h
index 72f693b..08b3e32 100644
--- a/dggui/button_base.h
+++ b/dggui/button_base.h
@@ -57,10 +57,10 @@ protected:
 	virtual void clicked() {}
 
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* e) override {};
-	virtual void buttonEvent(ButtonEvent* e) override;
-	virtual void mouseLeaveEvent() override;
-	virtual void mouseEnterEvent() override;
+	void repaintEvent(const RepaintEvent& e) override {};
+	void buttonEvent(const ButtonEvent& e) override;
+	void mouseLeaveEvent() override;
+	void mouseEnterEvent() override;
 
 	bool enabled{true};
 	bool in_button{false};
diff --git a/dggui/checkbox.cc b/dggui/checkbox.cc
index 8911862..f28534b 100644
--- a/dggui/checkbox.cc
+++ b/dggui/checkbox.cc
@@ -39,7 +39,7 @@ CheckBox::CheckBox(Widget* parent)
 {
 }
 
-void CheckBox::repaintEvent(RepaintEvent* repaintEvent)
+void CheckBox::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 	p.clear();
diff --git a/dggui/checkbox.h b/dggui/checkbox.h
index 1a323b6..281280e 100644
--- a/dggui/checkbox.h
+++ b/dggui/checkbox.h
@@ -39,7 +39,7 @@ public:
 
 protected:
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
 
 private:
 	Texture bg_on;
diff --git a/dggui/combobox.cc b/dggui/combobox.cc
index 33765e2..51e5868 100644
--- a/dggui/combobox.cc
+++ b/dggui/combobox.cc
@@ -40,7 +40,7 @@ void ComboBox::listboxSelectHandler()
 {
 	ButtonEvent buttonEvent;
 	buttonEvent.direction = Direction::down;
-	this->buttonEvent(&buttonEvent);
+	this->buttonEvent(buttonEvent);
 }
 
 ComboBox::ComboBox(Widget* parent)
@@ -95,7 +95,7 @@ static void drawArrow(Painter &p, int x, int y, int w, int h)
 	p.drawLine(x+(w/2), y+h, x+w, y);
 }
 
-void ComboBox::repaintEvent(RepaintEvent* repaintEvent)
+void ComboBox::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
@@ -129,7 +129,7 @@ void ComboBox::repaintEvent(RepaintEvent* repaintEvent)
 	}
 }
 
-void ComboBox::scrollEvent(ScrollEvent* scrollEvent)
+void ComboBox::scrollEvent(const ScrollEvent& scrollEvent)
 {
 	/*
 	scroll_offset += e->delta;
@@ -145,15 +145,15 @@ void ComboBox::scrollEvent(ScrollEvent* scrollEvent)
 	*/
 }
 
-void ComboBox::keyEvent(KeyEvent* keyEvent)
+void ComboBox::keyEvent(const KeyEvent& keyEvent)
 {
-	if(keyEvent->direction != Direction::up)
+	if(keyEvent.direction != Direction::up)
 	{
 		return;
 	}
 
 	/*
-	switch(keyEvent->keycode) {
+	switch(keyEvent.keycode) {
 	case Key::up:
 		{
 			selected--;
@@ -205,15 +205,15 @@ void ComboBox::keyEvent(KeyEvent* keyEvent)
 	*/
 }
 
-void ComboBox::buttonEvent(ButtonEvent* buttonEvent)
+void ComboBox::buttonEvent(const ButtonEvent& buttonEvent)
 {
 	// Ignore everything except left clicks.
-	if(buttonEvent->button != MouseButton::left)
+	if(buttonEvent.button != MouseButton::left)
 	{
 		return;
 	}
 
-	if(buttonEvent->direction != Direction::down)
+	if(buttonEvent.direction != Direction::down)
 	{
 		return;
 	}
diff --git a/dggui/combobox.h b/dggui/combobox.h
index a3ef8ac..5fe1909 100644
--- a/dggui/combobox.h
+++ b/dggui/combobox.h
@@ -54,10 +54,10 @@ public:
 
 	// From Widget:
 	bool isFocusable() override { return true; }
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
-	virtual void buttonEvent(ButtonEvent* buttonEvent) override;
-	virtual void scrollEvent(ScrollEvent* scrollEvent) override;
-	virtual void keyEvent(KeyEvent* keyEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
+	void buttonEvent(const ButtonEvent& buttonEvent) override;
+	void scrollEvent(const ScrollEvent& scrollEvent) override;
+	void keyEvent(const KeyEvent& keyEvent) override;
 
 	Notifier<std::string, std::string> valueChangedNotifier;
 
diff --git a/dggui/eventhandler.cc b/dggui/eventhandler.cc
index b2cf616..24cc467 100644
--- a/dggui/eventhandler.cc
+++ b/dggui/eventhandler.cc
@@ -143,7 +143,7 @@ void EventHandler::processEvents()
 					moveEvent->x -= widget->translateToWindowX();
 					moveEvent->y -= widget->translateToWindowY();
 
-					window.buttonDownFocus()->mouseMoveEvent(moveEvent);
+					window.buttonDownFocus()->mouseMoveEvent(*moveEvent);
 					break;
 				}
 
@@ -151,7 +151,7 @@ void EventHandler::processEvents()
 				{
 					moveEvent->x -= widget->translateToWindowX();
 					moveEvent->y -= widget->translateToWindowY();
-					widget->mouseMoveEvent(moveEvent);
+					widget->mouseMoveEvent(*moveEvent);
 				}
 			}
 			break;
@@ -182,7 +182,7 @@ void EventHandler::processEvents()
 						buttonEvent->x -= widget->translateToWindowX();
 						buttonEvent->y -= widget->translateToWindowY();
 
-						widget->buttonEvent(buttonEvent);
+						widget->buttonEvent(*buttonEvent);
 						window.setButtonDownFocus(nullptr);
 						break;
 					}
@@ -193,7 +193,7 @@ void EventHandler::processEvents()
 					buttonEvent->x -= widget->translateToWindowX();
 					buttonEvent->y -= widget->translateToWindowY();
 
-					widget->buttonEvent(buttonEvent);
+					widget->buttonEvent(*buttonEvent);
 
 					if((buttonEvent->direction == Direction::down) &&
 					   widget->catchMouse())
@@ -224,7 +224,7 @@ void EventHandler::processEvents()
 					scrollEvent->x -= widget->translateToWindowX();
 					scrollEvent->y -= widget->translateToWindowY();
 
-					widget->scrollEvent(scrollEvent);
+					widget->scrollEvent(*scrollEvent);
 				}
 			}
 			break;
@@ -241,7 +241,7 @@ void EventHandler::processEvents()
 				auto keyEvent = static_cast<KeyEvent*>(event.get());
 				if(window.keyboardFocus())
 				{
-					window.keyboardFocus()->keyEvent(keyEvent);
+					window.keyboardFocus()->keyEvent(*keyEvent);
 				}
 			}
 			break;
diff --git a/dggui/frame.cc b/dggui/frame.cc
index 3a163f1..d42a1df 100644
--- a/dggui/frame.cc
+++ b/dggui/frame.cc
@@ -60,7 +60,7 @@ FrameWidget::FrameWidget(Widget* parent, bool has_switch, bool has_help_text)
 	CONNECT(this, sizeChangeNotifier, this, &FrameWidget::sizeChanged);
 }
 
-void FrameWidget::repaintEvent(RepaintEvent* repaintEvent)
+void FrameWidget::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
diff --git a/dggui/frame.h b/dggui/frame.h
index dc8e17a..0e8cf5a 100644
--- a/dggui/frame.h
+++ b/dggui/frame.h
@@ -44,8 +44,8 @@ public:
 	virtual ~FrameWidget() = default;
 
 	// From Widget:
-	virtual bool isFocusable() override { return false; }
-	virtual bool catchMouse() override { return false; }
+	bool isFocusable() override { return false; }
+	bool catchMouse() override { return false; }
 
 	bool isSwitchedOn() { return is_switched_on; }
 
@@ -61,7 +61,7 @@ public:
 
 protected:
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
 
 	//! Callback for Widget::sizeChangeNotifier
 	void sizeChanged(int width, int height);
diff --git a/dggui/helpbutton.cc b/dggui/helpbutton.cc
index cc03112..a8c44d6 100644
--- a/dggui/helpbutton.cc
+++ b/dggui/helpbutton.cc
@@ -46,7 +46,7 @@ void HelpButton::setHelpText(const std::string& help_text)
 	tip.setText(help_text);
 }
 
-void HelpButton::repaintEvent(RepaintEvent* repaintEvent)
+void HelpButton::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
diff --git a/dggui/helpbutton.h b/dggui/helpbutton.h
index 639799a..b48c81b 100644
--- a/dggui/helpbutton.h
+++ b/dggui/helpbutton.h
@@ -44,7 +44,7 @@ public:
 
 protected:
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
 
 private:
 	void showHelpText();
diff --git a/dggui/knob.cc b/dggui/knob.cc
index 4f8ead0..148c736 100644
--- a/dggui/knob.cc
+++ b/dggui/knob.cc
@@ -82,40 +82,40 @@ void Knob::showValue(bool show_value)
 	this->show_value = show_value;
 }
 
-void Knob::scrollEvent(ScrollEvent* scrollEvent)
+void Knob::scrollEvent(const ScrollEvent& scrollEvent)
 {
-	float value = (current_value - (scrollEvent->delta / 200.0));
+	float value = (current_value - (scrollEvent.delta / 200.0));
 	internalSetValue(value);
 }
 
-void Knob::mouseMoveEvent(MouseMoveEvent* mouseMoveEvent)
+void Knob::mouseMoveEvent(const MouseMoveEvent& mouseMoveEvent)
 {
 	if(state == down)
 	{
-		if(mouse_offset_x == (mouseMoveEvent->x + (-1 * mouseMoveEvent->y)))
+		if(mouse_offset_x == (mouseMoveEvent.x + (-1 * mouseMoveEvent.y)))
 		{
 			return;
 		}
 
 		float dval =
-			mouse_offset_x - (mouseMoveEvent->x + (-1 * mouseMoveEvent->y));
+			mouse_offset_x - (mouseMoveEvent.x + (-1 * mouseMoveEvent.y));
 		float value = current_value - (dval / 300.0);
 
 		internalSetValue(value);
 
-		mouse_offset_x = mouseMoveEvent->x + (-1 * mouseMoveEvent->y);
+		mouse_offset_x = mouseMoveEvent.x + (-1 * mouseMoveEvent.y);
 	}
 }
 
-void Knob::keyEvent(KeyEvent* keyEvent)
+void Knob::keyEvent(const KeyEvent& keyEvent)
 {
-	if(keyEvent->direction != Direction::up)
+	if(keyEvent.direction != Direction::up)
 	{
 		return;
 	}
 
 	float value = current_value;
-	switch(keyEvent->keycode) {
+	switch(keyEvent.keycode) {
 	case Key::up:
 		value += 0.01;
 		break;
@@ -141,15 +141,15 @@ void Knob::keyEvent(KeyEvent* keyEvent)
 	internalSetValue(value);
 }
 
-void Knob::buttonEvent(ButtonEvent* buttonEvent)
+void Knob::buttonEvent(const ButtonEvent& buttonEvent)
 {
 	// Ignore everything except left clicks.
-	if(buttonEvent->button != MouseButton::left)
+	if(buttonEvent.button != MouseButton::left)
 	{
 		return;
 	}
 
-	if(buttonEvent->doubleClick)
+	if(buttonEvent.doubleClick)
 	{
 		float value = default_value;
 		value -= minimum;
@@ -158,23 +158,23 @@ void Knob::buttonEvent(ButtonEvent* buttonEvent)
 		return;
 	}
 
-	if(buttonEvent->direction == Direction::down)
+	if(buttonEvent.direction == Direction::down)
 	{
 		state = down;
-		mouse_offset_x = buttonEvent->x + (-1 * buttonEvent->y);
+		mouse_offset_x = buttonEvent.x + (-1 * buttonEvent.y);
 		return;
 	}
 
-	if(buttonEvent->direction == Direction::up)
+	if(buttonEvent.direction == Direction::up)
 	{
 		state = up;
-		mouse_offset_x = buttonEvent->x + (-1 * buttonEvent->y);
+		mouse_offset_x = buttonEvent.x + (-1 * buttonEvent.y);
 		clicked();
 		return;
 	}
 }
 
-void Knob::repaintEvent(RepaintEvent* repaintEvent)
+void Knob::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	int diameter = (width()>height()?height():width());
 	int radius = diameter / 2;
diff --git a/dggui/knob.h b/dggui/knob.h
index 851c9c6..ed2525c 100644
--- a/dggui/knob.h
+++ b/dggui/knob.h
@@ -56,11 +56,11 @@ protected:
 	virtual void clicked() {}
 
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
-	virtual void buttonEvent(ButtonEvent* buttonEvent) override;
-	virtual void mouseMoveEvent(MouseMoveEvent* mouseMoveEvent) override;
-	virtual void scrollEvent(ScrollEvent* scrollEvent) override;
-	virtual void keyEvent(KeyEvent* keyEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
+	void buttonEvent(const ButtonEvent& buttonEvent) override;
+	void mouseMoveEvent(const MouseMoveEvent& mouseMoveEvent) override;
+	void scrollEvent(const ScrollEvent& scrollEvent) override;
+	void keyEvent(const KeyEvent& keyEvent) override;
 
 private:
 	//! Sets the internal value and sends out the changed notification.
diff --git a/dggui/label.cc b/dggui/label.cc
index fc3f60e..3ce6d89 100644
--- a/dggui/label.cc
+++ b/dggui/label.cc
@@ -67,7 +67,7 @@ void Label::resizeToText()
 	resize(font.textWidth(_text) + border, font.textHeight());
 }
 
-void Label::repaintEvent(RepaintEvent* repaintEvent)
+void Label::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 	p.clear();
diff --git a/dggui/label.h b/dggui/label.h
index 453bc4f..ec4896a 100644
--- a/dggui/label.h
+++ b/dggui/label.h
@@ -55,7 +55,7 @@ public:
 
 protected:
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
 
 private:
 	std::string _text;
diff --git a/dggui/layout.h b/dggui/layout.h
index 860ecc2..e1b4092 100644
--- a/dggui/layout.h
+++ b/dggui/layout.h
@@ -91,7 +91,7 @@ public:
 	void setSpacing(size_t spacing);
 
 	// From Layout:
-	virtual void layout() override = 0;
+	void layout() override = 0;
 
 protected:
 	bool resizeChildren{false};
@@ -114,7 +114,7 @@ public:
 	void setHAlignment(HAlignment alignment);
 
 	// From BoxLayout:
-	virtual void layout() override;
+	void layout() override;
 
 protected:
 	HAlignment align;
@@ -136,7 +136,7 @@ public:
 	void setVAlignment(VAlignment alignment);
 
 	// From BoxLayout:
-	virtual void layout() override;
+	void layout() override;
 
 protected:
 	VAlignment align;
@@ -188,8 +188,8 @@ private:
 	};
 
 	CellSize calculateCellSize() const;
-	void moveAndResize(
-	    LayoutItem& item, GridRange const& range, CellSize cell_size) const;
+	void moveAndResize(LayoutItem& item, GridRange const& range,
+	                   CellSize cell_size) const;
 };
 
 } // dggui::
diff --git a/dggui/led.cc b/dggui/led.cc
index 6e1059c..9729299 100644
--- a/dggui/led.cc
+++ b/dggui/led.cc
@@ -46,7 +46,7 @@ void LED::setState(state_t state)
 	}
 }
 
-void LED::repaintEvent(RepaintEvent* repaintEvent)
+void LED::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	size_t h = height() - 1;
 	size_t w = width() - 1;
diff --git a/dggui/led.h b/dggui/led.h
index 7a1f55f..8536967 100644
--- a/dggui/led.h
+++ b/dggui/led.h
@@ -46,7 +46,7 @@ public:
 
 protected:
 	// From Widget:
-	void repaintEvent(RepaintEvent* repaintEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
 
 private:
 	state_t state;
diff --git a/dggui/lineedit.cc b/dggui/lineedit.cc
index 7e8bf86..f7c4ec7 100644
--- a/dggui/lineedit.cc
+++ b/dggui/lineedit.cc
@@ -71,7 +71,7 @@ std::string LineEdit::getText()
 	return _text;
 }
 
-void LineEdit::buttonEvent(ButtonEvent *buttonEvent)
+void LineEdit::buttonEvent(const ButtonEvent& buttonEvent)
 {
 	if(readOnly())
 	{
@@ -79,17 +79,17 @@ void LineEdit::buttonEvent(ButtonEvent *buttonEvent)
 	}
 
 	// Ignore everything except left clicks.
-	if(buttonEvent->button != MouseButton::left)
+	if(buttonEvent.button != MouseButton::left)
 	{
 		return;
 	}
 
-	if(buttonEvent->direction == Direction::down)
+	if(buttonEvent.direction == Direction::down)
 	{
 		for(int i = 0; i < (int)visibleText.length(); ++i)
 		{
 			int textWidth = font.textWidth(visibleText.substr(0, i));
-			if(buttonEvent->x < (textWidth + BORDER))
+			if(buttonEvent.x < (textWidth + BORDER))
 			{
 				pos = i + offsetPos;
 				break;
@@ -99,7 +99,7 @@ void LineEdit::buttonEvent(ButtonEvent *buttonEvent)
 	}
 }
 
-void LineEdit::keyEvent(KeyEvent *keyEvent)
+void LineEdit::keyEvent(const KeyEvent& keyEvent)
 {
 	if(readOnly())
 	{
@@ -108,9 +108,9 @@ void LineEdit::keyEvent(KeyEvent *keyEvent)
 
 	bool change = false;
 
-	if(keyEvent->direction == Direction::down)
+	if(keyEvent.direction == Direction::down)
 	{
-		switch(keyEvent->keycode) {
+		switch(keyEvent.keycode) {
 		case Key::left:
 			if(pos == 0)
 			{
@@ -176,7 +176,7 @@ void LineEdit::keyEvent(KeyEvent *keyEvent)
 			{
 				std::string pre = _text.substr(0, pos);
 				std::string post = _text.substr(pos, std::string::npos);
-				_text = pre + keyEvent->text + post;
+				_text = pre + keyEvent.text + post;
 				change = true;
 				pos++;
 			}
@@ -199,7 +199,7 @@ void LineEdit::keyEvent(KeyEvent *keyEvent)
 	}
 }
 
-void LineEdit::repaintEvent(RepaintEvent *repaintEvent)
+void LineEdit::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
diff --git a/dggui/lineedit.h b/dggui/lineedit.h
index c702c47..c419da9 100644
--- a/dggui/lineedit.h
+++ b/dggui/lineedit.h
@@ -54,9 +54,9 @@ public:
 	Notifier<> enterPressedNotifier;
 
 	//protected:
-	virtual void keyEvent(KeyEvent *keyEvent) override;
-	virtual void repaintEvent(RepaintEvent *repaintEvent) override;
-	virtual void buttonEvent(ButtonEvent *buttonEvent) override;
+	void keyEvent(const KeyEvent& keyEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
+	void buttonEvent(const ButtonEvent& buttonEvent) override;
 
 protected:
 	virtual void textChanged() {}
diff --git a/dggui/listbox.cc b/dggui/listbox.cc
index 4513895..3f29527 100644
--- a/dggui/listbox.cc
+++ b/dggui/listbox.cc
@@ -81,7 +81,7 @@ void ListBox::clearSelectedValue()
 	basic.clearSelectedValue();
 }
 
-void ListBox::repaintEvent(RepaintEvent* repaintEvent)
+void ListBox::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
diff --git a/dggui/listbox.h b/dggui/listbox.h
index 75a4ea0..88795c7 100644
--- a/dggui/listbox.h
+++ b/dggui/listbox.h
@@ -54,8 +54,8 @@ public:
 	void clearSelectedValue();
 
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 	// Forwarded notifiers from ListBoxBasic::basic
 	Notifier<>& selectionNotifier;
diff --git a/dggui/listboxbasic.cc b/dggui/listboxbasic.cc
index dd58944..2dc02d0 100644
--- a/dggui/listboxbasic.cc
+++ b/dggui/listboxbasic.cc
@@ -140,7 +140,7 @@ void ListBoxBasic::onScrollBarValueChange(int value)
 	redraw();
 }
 
-void ListBoxBasic::repaintEvent(RepaintEvent* repaintEvent)
+void ListBoxBasic::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
@@ -190,20 +190,20 @@ void ListBoxBasic::repaintEvent(RepaintEvent* repaintEvent)
 	scroll.setMaximum(items.size());
 }
 
-void ListBoxBasic::scrollEvent(ScrollEvent* scrollEvent)
+void ListBoxBasic::scrollEvent(const ScrollEvent& scrollEvent)
 {
 	// forward scroll event to scroll bar.
 	scroll.scrollEvent(scrollEvent);
 }
 
-void ListBoxBasic::keyEvent(KeyEvent* keyEvent)
+void ListBoxBasic::keyEvent(const KeyEvent& keyEvent)
 {
-	if(keyEvent->direction != Direction::down)
+	if(keyEvent.direction != Direction::down)
 	{
 		return;
 	}
 
-	switch(keyEvent->keycode) {
+	switch(keyEvent.keycode) {
 	case Key::up:
 		if(marked == 0)
 		{
@@ -259,7 +259,7 @@ void ListBoxBasic::keyEvent(KeyEvent* keyEvent)
 		break;
 
 	case Key::character:
-		if(keyEvent->text == " ")
+		if(keyEvent.text == " ")
 		{
 			setSelection(marked);
 			//selectionNotifier();
@@ -278,20 +278,20 @@ void ListBoxBasic::keyEvent(KeyEvent* keyEvent)
 	redraw();
 }
 
-void ListBoxBasic::buttonEvent(ButtonEvent* buttonEvent)
+void ListBoxBasic::buttonEvent(const ButtonEvent& buttonEvent)
 {
 	// Ignore everything except left clicks.
-	if(buttonEvent->button != MouseButton::left)
+	if(buttonEvent.button != MouseButton::left)
 	{
 		return;
 	}
 
-	if((buttonEvent->x > ((int)width() - btn_size)) &&
-	   (buttonEvent->y < ((int)width() - 1)))
+	if((buttonEvent.x > ((int)width() - btn_size)) &&
+	   (buttonEvent.y < ((int)width() - 1)))
 	{
-		if(buttonEvent->y > 0 && buttonEvent->y < btn_size)
+		if(buttonEvent.y > 0 && buttonEvent.y < btn_size)
 		{
-			if(buttonEvent->direction == Direction::up)
+			if(buttonEvent.direction == Direction::up)
 			{
 				return;
 			}
@@ -299,10 +299,10 @@ void ListBoxBasic::buttonEvent(ButtonEvent* buttonEvent)
 			return;
 		}
 
-		if(buttonEvent->y > ((int)height() - btn_size) &&
-		   buttonEvent->y < ((int)height() - 1))
+		if(buttonEvent.y > ((int)height() - btn_size) &&
+		   buttonEvent.y < ((int)height() - 1))
 		{
-			if(buttonEvent->direction == Direction::up)
+			if(buttonEvent.direction == Direction::up)
 			{
 				return;
 			}
@@ -311,14 +311,14 @@ void ListBoxBasic::buttonEvent(ButtonEvent* buttonEvent)
 		}
 	}
 
-	if(buttonEvent->direction == Direction::up)
+	if(buttonEvent.direction == Direction::up)
 	{
 		int skip = scroll.value();
 		size_t yoffset = padding / 2;
 		for(int idx = skip; idx < (int)items.size(); idx++)
 		{
 			yoffset += font.textHeight() + padding;
-			if(buttonEvent->y < (int)yoffset - (padding / 2))
+			if(buttonEvent.y < (int)yoffset - (padding / 2))
 			{
 				setSelection(idx);
 				marked = selected;
@@ -330,14 +330,14 @@ void ListBoxBasic::buttonEvent(ButtonEvent* buttonEvent)
 		redraw();
 	}
 
-	if(buttonEvent->direction != Direction::up)
+	if(buttonEvent.direction != Direction::up)
 	{
 		int skip = scroll.value();
 		size_t yoffset = padding / 2;
 		for(int idx = skip; idx < (int)items.size(); idx++)
 		{
 			yoffset += font.textHeight() + padding;
-			if(buttonEvent->y < ((int)yoffset - (padding / 2)))
+			if(buttonEvent.y < ((int)yoffset - (padding / 2)))
 			{
 				marked = idx;
 				break;
@@ -347,7 +347,7 @@ void ListBoxBasic::buttonEvent(ButtonEvent* buttonEvent)
 		redraw();
 	}
 
-	if(buttonEvent->doubleClick)
+	if(buttonEvent.doubleClick)
 	{
 		selectionNotifier();
 	}
diff --git a/dggui/listboxbasic.h b/dggui/listboxbasic.h
index 3d6515d..93badac 100644
--- a/dggui/listboxbasic.h
+++ b/dggui/listboxbasic.h
@@ -67,17 +67,17 @@ public:
 	Notifier<> valueChangedNotifier;
 
 	// From Widget:
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 protected:
 	void onScrollBarValueChange(int value);
 
 	// From Widget:
 	bool isFocusable() override { return true; }
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
-	virtual void buttonEvent(ButtonEvent* buttonEvent) override;
-	virtual void keyEvent(KeyEvent* keyEvent) override;
-	virtual void scrollEvent(ScrollEvent* scrollEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
+	void buttonEvent(const ButtonEvent& buttonEvent) override;
+	void keyEvent(const KeyEvent& keyEvent) override;
+	void scrollEvent(const ScrollEvent& scrollEvent) override;
 
 	ScrollBar scroll;
 
diff --git a/dggui/listboxthin.cc b/dggui/listboxthin.cc
index b92def3..994d256 100644
--- a/dggui/listboxthin.cc
+++ b/dggui/listboxthin.cc
@@ -76,7 +76,7 @@ std::string ListBoxThin::selectedValue()
 	return basic.selectedValue();
 }
 
-void ListBoxThin::repaintEvent(RepaintEvent* repaintEvent)
+void ListBoxThin::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
diff --git a/dggui/listboxthin.h b/dggui/listboxthin.h
index 0305a04..578e9d1 100644
--- a/dggui/listboxthin.h
+++ b/dggui/listboxthin.h
@@ -55,8 +55,8 @@ public:
 	std::string selectedValue();
 
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
-	virtual void resize(std::size_t height, std::size_t width) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
+	void resize(std::size_t height, std::size_t width) override;
 
 	// Forwarded notifier from ListBoxBasic::basic
 	Notifier<>& selectionNotifier;
diff --git a/dggui/nativewindow_cocoa.h b/dggui/nativewindow_cocoa.h
index e17d4af..aa7e4b3 100644
--- a/dggui/nativewindow_cocoa.h
+++ b/dggui/nativewindow_cocoa.h
@@ -42,21 +42,21 @@ public:
 	~NativeWindowCocoa();
 
 	// From NativeWindow:
-	virtual void setFixedSize(std::size_t width, std::size_t height) override;
-	virtual void setAlwaysOnTop(bool always_on_top) override;
-	virtual void resize(std::size_t width, std::size_t height) override;
-	virtual std::pair<std::size_t, std::size_t> getSize() const override;
-	virtual void move(int x, int y) override;
-	virtual std::pair<int, int> getPosition() const override;
-	virtual void show() override;
-	virtual void hide() override;
-	virtual bool visible() const override;
-	virtual void setCaption(const std::string &caption) override;
-	virtual void redraw(const Rect& dirty_rect) override;
-	virtual void grabMouse(bool grab) override;
-	virtual EventQueue getEvents() override;
-	virtual void* getNativeWindowHandle() const override;
-	virtual Point translateToScreen(const Point& point) override;
+	void setFixedSize(std::size_t width, std::size_t height) override;
+	void setAlwaysOnTop(bool always_on_top) override;
+	void resize(std::size_t width, std::size_t height) override;
+	std::pair<std::size_t, std::size_t> getSize() const override;
+	void move(int x, int y) override;
+	std::pair<int, int> getPosition() const override;
+	void show() override;
+	void hide() override;
+	bool visible() const override;
+	void setCaption(const std::string &caption) override;
+	void redraw(const Rect& dirty_rect) override;
+	void grabMouse(bool grab) override;
+	EventQueue getEvents() override;
+	void* getNativeWindowHandle() const override;
+	Point translateToScreen(const Point& point) override;
 
 	// Expose friend members of Window to ObjC++ implementation.
 	class Window& getWindow();
diff --git a/dggui/powerbutton.cc b/dggui/powerbutton.cc
index 8a204f2..7bffc43 100644
--- a/dggui/powerbutton.cc
+++ b/dggui/powerbutton.cc
@@ -42,7 +42,7 @@ void PowerButton::setEnabled(bool enabled)
 	redraw();
 }
 
-void PowerButton::repaintEvent(RepaintEvent* repaintEvent)
+void PowerButton::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
diff --git a/dggui/powerbutton.h b/dggui/powerbutton.h
index a752c53..b0313f9 100644
--- a/dggui/powerbutton.h
+++ b/dggui/powerbutton.h
@@ -42,7 +42,7 @@ public:
 
 protected:
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
 
 	bool enabled = true;
 
diff --git a/dggui/progressbar.cc b/dggui/progressbar.cc
index 1f833f9..c9e21e8 100644
--- a/dggui/progressbar.cc
+++ b/dggui/progressbar.cc
@@ -65,7 +65,7 @@ void ProgressBar::setValue(std::size_t value)
 	}
 }
 
-void ProgressBar::repaintEvent(RepaintEvent* repaintEvent)
+void ProgressBar::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
diff --git a/dggui/progressbar.h b/dggui/progressbar.h
index a67687b..10b073c 100644
--- a/dggui/progressbar.h
+++ b/dggui/progressbar.h
@@ -57,7 +57,7 @@ public:
 
 protected:
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
 
 private:
 	ProgressBarState state{ProgressBarState::Blue};
diff --git a/dggui/scrollbar.cc b/dggui/scrollbar.cc
index e78aab3..00ed727 100644
--- a/dggui/scrollbar.cc
+++ b/dggui/scrollbar.cc
@@ -117,7 +117,7 @@ static void drawArrow(Painter &p, int x, int y, int w, int h)
 	p.drawLine(x + (w / 2), y + h, x + w, y);
 }
 
-void ScrollBar::repaintEvent(RepaintEvent* repaintEvent)
+void ScrollBar::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
@@ -150,19 +150,19 @@ void ScrollBar::repaintEvent(RepaintEvent* repaintEvent)
 	p.drawLine(0, height() - width(), width(), height() - width());
 }
 
-void ScrollBar::scrollEvent(ScrollEvent* scrollEvent)
+void ScrollBar::scrollEvent(const ScrollEvent& scrollEvent)
 {
-	setValue(value() + scrollEvent->delta);
+	setValue(value() + scrollEvent.delta);
 }
 
-void ScrollBar::mouseMoveEvent(MouseMoveEvent* mouseMoveEvent)
+void ScrollBar::mouseMoveEvent(const MouseMoveEvent& mouseMoveEvent)
 {
 	if(!dragging)
 	{
 		return;
 	}
 
-	float delta = yOffset - mouseMoveEvent->y;
+	float delta = yOffset - mouseMoveEvent.y;
 
 	int h = height() - 2 * width() - 3;
 	delta /= (float)h / (float)maxValue;
@@ -174,17 +174,17 @@ void ScrollBar::mouseMoveEvent(MouseMoveEvent* mouseMoveEvent)
 	}
 }
 
-void ScrollBar::buttonEvent(ButtonEvent* buttonEvent)
+void ScrollBar::buttonEvent(const ButtonEvent& buttonEvent)
 {
 	// Ignore everything except left clicks.
-	if(buttonEvent->button != MouseButton::left)
+	if(buttonEvent.button != MouseButton::left)
 	{
 		return;
 	}
 
-	if((buttonEvent->y < (int)width()) && buttonEvent->y > 0)
+	if((buttonEvent.y < (int)width()) && buttonEvent.y > 0)
 	{
-		if(buttonEvent->direction == Direction::down)
+		if(buttonEvent.direction == Direction::down)
 		{
 			addValue(-1);
 		}
@@ -192,10 +192,10 @@ void ScrollBar::buttonEvent(ButtonEvent* buttonEvent)
 		return;
 	}
 
-	if((buttonEvent->y > ((int)height() - (int)width())) &&
-	   (buttonEvent->y < (int)height()))
+	if((buttonEvent.y > ((int)height() - (int)width())) &&
+	   (buttonEvent.y < (int)height()))
 	{
-		if(buttonEvent->direction == Direction::down)
+		if(buttonEvent.direction == Direction::down)
 		{
 			addValue(1);
 		}
@@ -203,13 +203,13 @@ void ScrollBar::buttonEvent(ButtonEvent* buttonEvent)
 		return;
 	}
 
-	if(buttonEvent->direction == Direction::down)
+	if(buttonEvent.direction == Direction::down)
 	{
-		yOffset = buttonEvent->y;
+		yOffset = buttonEvent.y;
 		valueOffset = value();
 	}
 
-	dragging = (buttonEvent->direction == Direction::down);
+	dragging = (buttonEvent.direction == Direction::down);
 }
 
 } // dggui::
diff --git a/dggui/scrollbar.h b/dggui/scrollbar.h
index 9bc4de8..c300696 100644
--- a/dggui/scrollbar.h
+++ b/dggui/scrollbar.h
@@ -57,10 +57,10 @@ public:
 protected:
 	// From Widget:
 	bool catchMouse() override { return true; }
-	void scrollEvent(ScrollEvent* scrollEvent) override;
-	void repaintEvent(RepaintEvent* repaintEvent) override;
-	void buttonEvent(ButtonEvent* buttonEvent) override;
-	void mouseMoveEvent(MouseMoveEvent* mouseMoveEvent) override;
+	void scrollEvent(const ScrollEvent& scrollEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
+	void buttonEvent(const ButtonEvent& buttonEvent) override;
+	void mouseMoveEvent(const MouseMoveEvent& mouseMoveEvent) override;
 
 private:
 	int maxValue{100};
diff --git a/dggui/slider.cc b/dggui/slider.cc
index bb42f34..1a6ffda 100644
--- a/dggui/slider.cc
+++ b/dggui/slider.cc
@@ -105,7 +105,7 @@ void Slider::setEnabled(bool enabled)
 	redraw();
 }
 
-void Slider::repaintEvent(RepaintEvent* repaintEvent)
+void Slider::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	Painter p(*this);
 
@@ -125,28 +125,28 @@ void Slider::repaintEvent(RepaintEvent* repaintEvent)
 	p.drawImage(button_x, button_y, button);
 }
 
-void Slider::buttonEvent(ButtonEvent* buttonEvent)
+void Slider::buttonEvent(const ButtonEvent& buttonEvent)
 {
 	// Ignore everything except left clicks.
-	if(!enabled || buttonEvent->button != MouseButton::left)
+	if(!enabled || buttonEvent.button != MouseButton::left)
 	{
 		return;
 	}
 
-	if(buttonEvent->direction == Direction::down)
+	if(buttonEvent.direction == Direction::down)
 	{
 		state = State::down;
-		recomputeCurrentValue(buttonEvent->x);
+		recomputeCurrentValue(buttonEvent.x);
 
 		redraw();
 		clickNotifier();
 		valueChangedNotifier(current_value);
 	}
 
-	if(buttonEvent->direction == Direction::up)
+	if(buttonEvent.direction == Direction::up)
 	{
 		state = State::up;
-		recomputeCurrentValue(buttonEvent->x);
+		recomputeCurrentValue(buttonEvent.x);
 
 		redraw();
 		clickNotifier();
@@ -154,11 +154,11 @@ void Slider::buttonEvent(ButtonEvent* buttonEvent)
 	}
 }
 
-void Slider::mouseMoveEvent(MouseMoveEvent* mouseMoveEvent)
+void Slider::mouseMoveEvent(const MouseMoveEvent& mouseMoveEvent)
 {
 	if(state == State::down)
 	{
-		recomputeCurrentValue(mouseMoveEvent->x);
+		recomputeCurrentValue(mouseMoveEvent.x);
 
 		redraw();
 		clickNotifier();
@@ -166,11 +166,11 @@ void Slider::mouseMoveEvent(MouseMoveEvent* mouseMoveEvent)
 	}
 }
 
-void Slider::scrollEvent(ScrollEvent* scrollEvent)
+void Slider::scrollEvent(const ScrollEvent& scrollEvent)
 {
 	if (!enabled) { return; }
 
-	current_value -= scrollEvent->delta/(float)getControlWidth();
+	current_value -= scrollEvent.delta/(float)getControlWidth();
 	if (current_value < 0.)
 	{
 		current_value = 0.;
diff --git a/dggui/slider.h b/dggui/slider.h
index b249c91..e93cb11 100644
--- a/dggui/slider.h
+++ b/dggui/slider.h
@@ -62,10 +62,11 @@ public:
 	Notifier<float> valueChangedNotifier; // (float value)
 
 protected:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
-	virtual void buttonEvent(ButtonEvent* buttonEvent) override;
-	virtual void mouseMoveEvent(MouseMoveEvent* mouseMoveEvent) override;
-	virtual void scrollEvent(ScrollEvent* scrollEvent) override;
+	// From Widget:
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
+	void buttonEvent(const ButtonEvent& buttonEvent) override;
+	void mouseMoveEvent(const MouseMoveEvent& mouseMoveEvent) override;
+	void scrollEvent(const ScrollEvent& scrollEvent) override;
 
 	bool enabled = true;;
 
diff --git a/dggui/tabbutton.cc b/dggui/tabbutton.cc
index a2b0549..c681131 100644
--- a/dggui/tabbutton.cc
+++ b/dggui/tabbutton.cc
@@ -90,7 +90,7 @@ TabID TabButton::getID() const
 	return tab_id;
 }
 
-void TabButton::repaintEvent(RepaintEvent* e)
+void TabButton::repaintEvent(const RepaintEvent& e)
 {
 	Painter p(*this);
 
@@ -119,9 +119,9 @@ void TabButton::repaintEvent(RepaintEvent* e)
 	p.drawText(x, y, font, text, true);
 }
 
-void TabButton::scrollEvent(ScrollEvent* scroll_event)
+void TabButton::scrollEvent(const ScrollEvent& scroll_event)
 {
-	scrollNotifier(scroll_event->delta);
+	scrollNotifier(scroll_event.delta);
 }
 
 void TabButton::clickHandler()
diff --git a/dggui/tabbutton.h b/dggui/tabbutton.h
index ac9a37c..7a51ad6 100644
--- a/dggui/tabbutton.h
+++ b/dggui/tabbutton.h
@@ -58,8 +58,8 @@ public:
 
 protected:
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* e) override;
-	virtual void scrollEvent(ScrollEvent* scroll_event) override;
+	void repaintEvent(const RepaintEvent& e) override;
+	void scrollEvent(const ScrollEvent& scroll_event) override;
 
 private:
 	TabID tab_id;
diff --git a/dggui/textedit.cc b/dggui/textedit.cc
index f8aeab7..52830b7 100644
--- a/dggui/textedit.cc
+++ b/dggui/textedit.cc
@@ -149,7 +149,7 @@ void TextEdit::preprocessText()
 	}
 }
 
-void TextEdit::repaintEvent(RepaintEvent* repaintEvent)
+void TextEdit::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	if(needs_preprocessing)
 	{
@@ -187,9 +187,9 @@ void TextEdit::repaintEvent(RepaintEvent* repaintEvent)
 	}
 }
 
-void TextEdit::scrollEvent(ScrollEvent* scrollEvent)
+void TextEdit::scrollEvent(const ScrollEvent& scrollEvent)
 {
-	scroll.setValue(scroll.value() + scrollEvent->delta);
+	scroll.setValue(scroll.value() + scrollEvent.delta);
 }
 
 void TextEdit::scrolled(int value)
diff --git a/dggui/textedit.h b/dggui/textedit.h
index c07774b..ffc280a 100644
--- a/dggui/textedit.h
+++ b/dggui/textedit.h
@@ -64,8 +64,8 @@ public:
 
 protected:
 	// From Widget
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
-	void scrollEvent(ScrollEvent* scrollEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
+	void scrollEvent(const ScrollEvent& scrollEvent) override;
 
 private:
 	void scrolled(int value);
diff --git a/dggui/toggle.cc b/dggui/toggle.cc
index e655a65..dc62784 100644
--- a/dggui/toggle.cc
+++ b/dggui/toggle.cc
@@ -33,15 +33,15 @@ Toggle::Toggle(Widget* parent) : Widget(parent)
 {
 }
 
-void Toggle::buttonEvent(ButtonEvent* buttonEvent)
+void Toggle::buttonEvent(const ButtonEvent& buttonEvent)
 {
 	// Ignore everything except left clicks.
-	if(buttonEvent->button != MouseButton::left)
+	if(buttonEvent.button != MouseButton::left)
 	{
 		return;
 	}
 
-	if((buttonEvent->direction == Direction::up) || buttonEvent->doubleClick)
+	if((buttonEvent.direction == Direction::up) || buttonEvent.doubleClick)
 	{
 		buttonDown = false;
 		clicked = false;
diff --git a/dggui/toggle.h b/dggui/toggle.h
index 0fa844b..e308822 100644
--- a/dggui/toggle.h
+++ b/dggui/toggle.h
@@ -52,9 +52,9 @@ public:
 
 protected:
 	// From Widget:
-	virtual void buttonEvent(ButtonEvent* buttonEvent) override;
-	virtual void mouseLeaveEvent() override;
-	virtual void mouseEnterEvent() override;
+	void buttonEvent(const ButtonEvent& buttonEvent) override;
+	void mouseLeaveEvent() override;
+	void mouseEnterEvent() override;
 
 	bool state{false};
 	bool clicked{false};
diff --git a/dggui/tooltip.cc b/dggui/tooltip.cc
index b55b45e..c143cbd 100644
--- a/dggui/tooltip.cc
+++ b/dggui/tooltip.cc
@@ -57,7 +57,7 @@ void Tooltip::resize(std::size_t width, std::size_t height)
 	Widget::resize(width, height);
 }
 
-void Tooltip::repaintEvent(RepaintEvent* repaintEvent)
+void Tooltip::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	if(needs_preprocessing)
 	{
@@ -189,9 +189,9 @@ void Tooltip::show()
 	window()->setMouseFocus(this);
 }
 
-void Tooltip::buttonEvent(ButtonEvent* buttonEvent)
+void Tooltip::buttonEvent(const ButtonEvent& buttonEvent)
 {
-	if(buttonEvent->direction == Direction::down)
+	if(buttonEvent.direction == Direction::down)
 	{
 		hide();
 	}
diff --git a/dggui/tooltip.h b/dggui/tooltip.h
index 1ba1cd8..63bd06c 100644
--- a/dggui/tooltip.h
+++ b/dggui/tooltip.h
@@ -49,11 +49,11 @@ public:
 	void setText(const std::string& text);
 
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaint_event) override;
-	virtual void resize(std::size_t height, std::size_t width) override;
-	virtual void mouseLeaveEvent() override;
-	virtual void show() override;
-	virtual void buttonEvent(ButtonEvent* buttonEvent) override;
+	void repaintEvent(const RepaintEvent& repaint_event) override;
+	void resize(std::size_t height, std::size_t width) override;
+	void mouseLeaveEvent() override;
+	void show() override;
+	void buttonEvent(const ButtonEvent& buttonEvent) override;
 
 private:
 	void preprocessText();
diff --git a/dggui/verticalline.cc b/dggui/verticalline.cc
index d068b82..1528ec7 100644
--- a/dggui/verticalline.cc
+++ b/dggui/verticalline.cc
@@ -37,7 +37,7 @@ VerticalLine::VerticalLine(Widget *parent)
 {
 }
 
-void VerticalLine::repaintEvent(RepaintEvent* repaintEvent)
+void VerticalLine::repaintEvent(const RepaintEvent& repaintEvent)
 {
 	if(height() < 2)
 	{
diff --git a/dggui/verticalline.h b/dggui/verticalline.h
index 2479d0d..2099913 100644
--- a/dggui/verticalline.h
+++ b/dggui/verticalline.h
@@ -41,7 +41,7 @@ public:
 
 protected:
 	// From Widget:
-	virtual void repaintEvent(RepaintEvent* repaintEvent) override;
+	void repaintEvent(const RepaintEvent& repaintEvent) override;
 
 private:
 	Image vline;
diff --git a/dggui/widget.cc b/dggui/widget.cc
index 077fa72..07cbd19 100644
--- a/dggui/widget.cc
+++ b/dggui/widget.cc
@@ -244,7 +244,7 @@ std::vector<PixelBufferAlpha*> Widget::getPixelBuffers()
 
 	if(dirty)
 	{
-		repaintEvent(nullptr);
+		repaintEvent({});
 		pixbuf.dirty = true;
 		dirty = false;
 	}
diff --git a/dggui/widget.h b/dggui/widget.h
index bf391c5..6f19809 100644
--- a/dggui/widget.h
+++ b/dggui/widget.h
@@ -71,12 +71,12 @@ public:
 	void redraw();
 
 	// From LayoutItem
-	virtual void resize(std::size_t width, std::size_t height) override;
-	virtual void move(int x, int y) override;
-	virtual int x() const override;
-	virtual int y() const override;
-	virtual std::size_t width() const override;
-	virtual std::size_t height() const override;
+	void resize(std::size_t width, std::size_t height) override;
+	void move(int x, int y) override;
+	int x() const override;
+	int y() const override;
+	std::size_t width() const override;
+	std::size_t height() const override;
 
 	Point position() const;
 
@@ -90,11 +90,11 @@ public:
 	void removeChild(Widget* widget);
 	void reparent(Widget* parent);
 
-	virtual void repaintEvent(RepaintEvent* repaintEvent) {}
-	virtual void mouseMoveEvent(MouseMoveEvent* mouseMoveEvent) {}
-	virtual void buttonEvent(ButtonEvent* buttonEvent) {}
-	virtual void scrollEvent(ScrollEvent* scrollEvent) {}
-	virtual void keyEvent(KeyEvent* keyEvent) {}
+	virtual void repaintEvent(const RepaintEvent& repaintEvent) {}
+	virtual void mouseMoveEvent(const MouseMoveEvent& mouseMoveEvent) {}
+	virtual void buttonEvent(const ButtonEvent& buttonEvent) {}
+	virtual void scrollEvent(const ScrollEvent& scrollEvent) {}
+	virtual void keyEvent(const KeyEvent& keyEvent) {}
 	virtual void mouseLeaveEvent() {}
 	virtual void mouseEnterEvent() {}
 
diff --git a/plugingui/bleedcontrolframecontent.h b/plugingui/bleedcontrolframecontent.h
index fadb98e..f7b3227 100644
--- a/plugingui/bleedcontrolframecontent.h
+++ b/plugingui/bleedcontrolframecontent.h
@@ -44,7 +44,7 @@ public:
 	                         SettingsNotifier& settings_notifier);
 
 	// From Widget
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 	void setEnabled(bool enabled);
 
diff --git a/plugingui/diskstreamingframecontent.h b/plugingui/diskstreamingframecontent.h
index 10ed90a..14ae855 100644
--- a/plugingui/diskstreamingframecontent.h
+++ b/plugingui/diskstreamingframecontent.h
@@ -46,7 +46,7 @@ public:
 	                          SettingsNotifier& settings_notifier);
 
 	// From Widget
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 private:
 	void limitSettingsValueChanged(std::size_t value);
diff --git a/plugingui/drumkitframecontent.h b/plugingui/drumkitframecontent.h
index 4c5cc9e..ac52a96 100644
--- a/plugingui/drumkitframecontent.h
+++ b/plugingui/drumkitframecontent.h
@@ -48,7 +48,7 @@ public:
 	BrowseFile(dggui::Widget* parent);
 
 	// From Widget
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 	std::size_t getLineEditWidth();
 	std::size_t getButtonWidth();
@@ -77,7 +77,7 @@ public:
 	                    Config& config);
 
 	// From Widget
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 	void kitBrowseClick();
 	void midimapBrowseClick();
diff --git a/plugingui/drumkittab.cc b/plugingui/drumkittab.cc
index 6323e94..1245bba 100644
--- a/plugingui/drumkittab.cc
+++ b/plugingui/drumkittab.cc
@@ -82,13 +82,13 @@ void DrumkitTab::resize(std::size_t width, std::size_t height)
 	                           height-instrument_name_label.height()-5);
 }
 
-void DrumkitTab::buttonEvent(dggui::ButtonEvent* buttonEvent)
+void DrumkitTab::buttonEvent(const dggui::ButtonEvent& buttonEvent)
 {
 	if(map_image)
 	{
-		if(buttonEvent->button == dggui::MouseButton::right)
+		if(buttonEvent.button == dggui::MouseButton::right)
 		{
-			if(buttonEvent->direction == dggui::Direction::down)
+			if(buttonEvent.direction == dggui::Direction::down)
 			{
 				dggui::Painter painter(*this);
 				painter.drawImage(drumkit_image_x, drumkit_image_y, *map_image);
@@ -97,7 +97,7 @@ void DrumkitTab::buttonEvent(dggui::ButtonEvent* buttonEvent)
 				return;
 			}
 
-			if(buttonEvent->direction == dggui::Direction::up)
+			if(buttonEvent.direction == dggui::Direction::up)
 			{
 				dggui::Painter painter(*this);
 				painter.clear();
@@ -112,16 +112,16 @@ void DrumkitTab::buttonEvent(dggui::ButtonEvent* buttonEvent)
 		}
 	}
 
-	if(buttonEvent->button == dggui::MouseButton::left)
+	if(buttonEvent.button == dggui::MouseButton::left)
 	{
-		if(buttonEvent->direction == dggui::Direction::down)
+		if(buttonEvent.direction == dggui::Direction::down)
 		{
-			triggerAudition(buttonEvent->x, buttonEvent->y);
+			triggerAudition(buttonEvent.x, buttonEvent.y);
 			highlightInstrument(current_index);
 			redraw();
 		}
 
-		if(buttonEvent->direction == dggui::Direction::up)
+		if(buttonEvent.direction == dggui::Direction::up)
 		{
 			if(shows_instrument_overlay)
 			{
@@ -140,21 +140,21 @@ void DrumkitTab::buttonEvent(dggui::ButtonEvent* buttonEvent)
 	}
 }
 
-void DrumkitTab::scrollEvent(dggui::ScrollEvent* scrollEvent)
+void DrumkitTab::scrollEvent(const dggui::ScrollEvent& scrollEvent)
 {
-	current_velocity -=  0.01 * scrollEvent->delta;
+	current_velocity -=  0.01 * scrollEvent.delta;
 	current_velocity = std::max(std::min(current_velocity, 1.0f), 0.0f);
 	updateVelocityLabel();
 	velocity_label.resizeToText();
 
-	triggerAudition(scrollEvent->x, scrollEvent->y);
+	triggerAudition(scrollEvent.x, scrollEvent.y);
 }
 
-void DrumkitTab::mouseMoveEvent(dggui::MouseMoveEvent* mouseMoveEvent)
+void DrumkitTab::mouseMoveEvent(const dggui::MouseMoveEvent& mouseMoveEvent)
 {
 	// change to image coordinates
-	const auto x = mouseMoveEvent->x - drumkit_image_x;
-	const auto y = mouseMoveEvent->y - drumkit_image_y;
+	const auto x = mouseMoveEvent.x - drumkit_image_x;
+	const auto y = mouseMoveEvent.y - drumkit_image_y;
 
 	auto index = pos_to_colour_index(x, y);
 
diff --git a/plugingui/drumkittab.h b/plugingui/drumkittab.h
index ad89fb1..f513276 100644
--- a/plugingui/drumkittab.h
+++ b/plugingui/drumkittab.h
@@ -54,9 +54,9 @@ public:
 
 	// From dggui::Widget:
 	void resize(std::size_t width, std::size_t height) override;
-	void buttonEvent(dggui::ButtonEvent* buttonEvent) override;
-	void scrollEvent(dggui::ScrollEvent* scrollEvent) override;
-	void mouseMoveEvent(dggui::MouseMoveEvent* mouseMoveEvent) override;
+	void buttonEvent(const dggui::ButtonEvent& buttonEvent) override;
+	void scrollEvent(const dggui::ScrollEvent& scrollEvent) override;
+	void mouseMoveEvent(const dggui::MouseMoveEvent& mouseMoveEvent) override;
 	void mouseLeaveEvent() override;
 
 	void init(const std::string& image_file, const std::string& map_file);
diff --git a/plugingui/filebrowser.cc b/plugingui/filebrowser.cc
index d4fc009..433ece2 100644
--- a/plugingui/filebrowser.cc
+++ b/plugingui/filebrowser.cc
@@ -139,7 +139,7 @@ void FileBrowser::resize(std::size_t width, std::size_t height)
 	btn_sel.resize(btn_w, btn_h);
 }
 
-void FileBrowser::repaintEvent(dggui::RepaintEvent* repaintEvent)
+void FileBrowser::repaintEvent(const dggui::RepaintEvent& repaintEvent)
 {
 	dggui::Painter p(*this);
 	p.drawImageStretched(0,0, back, width(), height());
diff --git a/plugingui/filebrowser.h b/plugingui/filebrowser.h
index 0620ef3..eef3c33 100644
--- a/plugingui/filebrowser.h
+++ b/plugingui/filebrowser.h
@@ -54,8 +54,8 @@ public:
 
 	// From Widget:
 	bool isFocusable() override { return true; }
-	virtual void repaintEvent(dggui::RepaintEvent* repaintEvent) override;
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void repaintEvent(const dggui::RepaintEvent& repaintEvent) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 	//! Return the filename selected in the browser.
 	std::string getFilename() const;
diff --git a/plugingui/humaniservisualiser.cc b/plugingui/humaniservisualiser.cc
index 1045e31..426ec52 100644
--- a/plugingui/humaniservisualiser.cc
+++ b/plugingui/humaniservisualiser.cc
@@ -45,7 +45,7 @@ HumaniserVisualiser::HumaniserVisualiser(dggui::Widget* parent,
 	canvas.move(7, 7);
 }
 
-void HumaniserVisualiser::repaintEvent(dggui::RepaintEvent *repaintEvent)
+void HumaniserVisualiser::repaintEvent(const dggui::RepaintEvent& repaintEvent)
 {
 	dggui::Painter p(*this);
 
@@ -90,7 +90,7 @@ HumaniserVisualiser::Canvas::Canvas(dggui::Widget* parent,
 	        this, &HumaniserVisualiser::Canvas::velocityStddevChanged);
 }
 
-void HumaniserVisualiser::Canvas::repaintEvent(dggui::RepaintEvent *repaintEvent)
+void HumaniserVisualiser::Canvas::repaintEvent(const dggui::RepaintEvent& repaintEvent)
 {
 	if(width() < 1 || height() < 1)
 	{
diff --git a/plugingui/humaniservisualiser.h b/plugingui/humaniservisualiser.h
index 028f10d..75aabd7 100644
--- a/plugingui/humaniservisualiser.h
+++ b/plugingui/humaniservisualiser.h
@@ -45,8 +45,8 @@ public:
 	                    SettingsNotifier& settings_notifier);
 
 	// From Widget:
-	virtual void repaintEvent(dggui::RepaintEvent *repaintEvent) override;
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void repaintEvent(const dggui::RepaintEvent& repaintEvent) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 private:
 	dggui::TexturedBox box{getImageCache(), ":resources/widget.png",
@@ -62,7 +62,7 @@ private:
 		       SettingsNotifier& settings_notifier);
 
 		// From Widget:
-		virtual void repaintEvent(dggui::RepaintEvent *repaintEvent) override;
+		void repaintEvent(const dggui::RepaintEvent& repaintEvent) override;
 
 		void latencyEnabledChanged(bool enabled);
 		void velocityEnabledChanged(bool enabled);
diff --git a/plugingui/mainwindow.cc b/plugingui/mainwindow.cc
index a4ad7b5..357ae5d 100644
--- a/plugingui/mainwindow.cc
+++ b/plugingui/mainwindow.cc
@@ -81,7 +81,7 @@ bool MainWindow::processEvents()
 	return true;
 }
 
-void MainWindow::repaintEvent(dggui::RepaintEvent* repaintEvent)
+void MainWindow::repaintEvent(const dggui::RepaintEvent& repaintEvent)
 {
 	if(!visible())
 	{
diff --git a/plugingui/mainwindow.h b/plugingui/mainwindow.h
index ae0da8b..253800d 100644
--- a/plugingui/mainwindow.h
+++ b/plugingui/mainwindow.h
@@ -65,7 +65,7 @@ private:
 	void changeDrumkitTabVisibility(bool visible);
 
 	// From Widget
-	void repaintEvent(dggui::RepaintEvent* repaintEvent) override final;
+	void repaintEvent(const dggui::RepaintEvent& repaintEvent) override final;
 
 	Config config;
 	SettingsNotifier settings_notifier;
diff --git a/plugingui/powerwidget.cc b/plugingui/powerwidget.cc
index 9be0c48..b61fd82 100644
--- a/plugingui/powerwidget.cc
+++ b/plugingui/powerwidget.cc
@@ -66,7 +66,7 @@ void PowerWidget::chk_shelf(bool v)
 	settings.powermap_shelf.store(v);
 }
 
-void PowerWidget::repaintEvent(dggui::RepaintEvent *repaintEvent)
+void PowerWidget::repaintEvent(const dggui::RepaintEvent& repaintEvent)
 {
 	dggui::Painter p(*this);
 	box.setSize(width() - 59 - 64, height());
@@ -118,7 +118,7 @@ PowerWidget::Canvas::Canvas(dggui::Widget* parent,
 	parameterChangedFloat(0);
 }
 
-void PowerWidget::Canvas::repaintEvent(dggui::RepaintEvent *repaintEvent)
+void PowerWidget::Canvas::repaintEvent(const dggui::RepaintEvent& repaintEvent)
 {
 	if(width() < 1 || height() < 1)
 	{
@@ -214,20 +214,20 @@ void PowerWidget::Canvas::repaintEvent(dggui::RepaintEvent *repaintEvent)
 	p.drawText(8, height() / 2 - (font.textWidth(_("out")) / 2), font, _("out"), false, true);
 }
 
-void PowerWidget::Canvas::buttonEvent(dggui::ButtonEvent* buttonEvent)
+void PowerWidget::Canvas::buttonEvent(const dggui::ButtonEvent& buttonEvent)
 {
 	const float x0 = brd;
 	const float y0 = brd;
 	const float width0 = (int)width() - 2 * brd;
 	const float height0 = (int)height() - 2 * brd;
 
-	float mx0 = (float)(buttonEvent->x - x0) / width0;
-	float my0 = (float)(((int)height() - buttonEvent->y) - y0) / height0;
+	float mx0 = (float)(buttonEvent.x - x0) / width0;
+	float my0 = (float)(((int)height() - buttonEvent.y) - y0) / height0;
 
 	float radius_x = radius * 2;
 	float radius_y = radius * width0 / height0 * 2;
 
-	switch(buttonEvent->direction)
+	switch(buttonEvent.direction)
 	{
 	case dggui::Direction::up:
 		in_point = -1;
@@ -262,15 +262,15 @@ float clamp(float val, float min, float max)
 }
 }
 
-void PowerWidget::Canvas::mouseMoveEvent(dggui::MouseMoveEvent* mouseMoveEvent)
+void PowerWidget::Canvas::mouseMoveEvent(const dggui::MouseMoveEvent& mouseMoveEvent)
 {
 	const float x0 = brd;
 	const float y0 = brd;
 	const float width0 = (int)width() - 2 * brd;
 	const float height0 = (int)height() - 2 * brd;
 
-	float mx0 = (float)(mouseMoveEvent->x - x0) / width0;
-	float my0 = (float)(((int)height() - mouseMoveEvent->y) - y0) / height0;
+	float mx0 = (float)(mouseMoveEvent.x - x0) / width0;
+	float my0 = (float)(((int)height() - mouseMoveEvent.y) - y0) / height0;
 
 	switch(in_point)
 	{
@@ -296,18 +296,18 @@ void PowerWidget::Canvas::mouseMoveEvent(dggui::MouseMoveEvent* mouseMoveEvent)
 	switch(in_point)
 	{
 	case 0:
-		settings.fixed0_x.store(clamp((float)mouseMoveEvent->x / width()));
-		settings.fixed0_y.store(1.0f - clamp((float)mouseMoveEvent->y / height()));
+		settings.fixed0_x.store(clamp((float)mouseMoveEvent.x / width()));
+		settings.fixed0_y.store(1.0f - clamp((float)mouseMoveEvent.y / height()));
 		redraw();
 		break;
 	case 1:
-		settings.fixed1_x.store(clamp((float)mouseMoveEvent->x / width()));
-		settings.fixed1_y.store(1.0f - clamp((float)mouseMoveEvent->y / height()));
+		settings.fixed1_x.store(clamp((float)mouseMoveEvent.x / width()));
+		settings.fixed1_y.store(1.0f - clamp((float)mouseMoveEvent.y / height()));
 		redraw();
 		break;
 	case 2:
-		settings.fixed2_x.store(clamp((float)mouseMoveEvent->x / width()));
-		settings.fixed2_y.store(1.0f - clamp((float)mouseMoveEvent->y / height()));
+		settings.fixed2_x.store(clamp((float)mouseMoveEvent.x / width()));
+		settings.fixed2_y.store(1.0f - clamp((float)mouseMoveEvent.y / height()));
 		redraw();
 		break;
 	default:
diff --git a/plugingui/powerwidget.h b/plugingui/powerwidget.h
index 3a7bb8e..6080b37 100644
--- a/plugingui/powerwidget.h
+++ b/plugingui/powerwidget.h
@@ -51,8 +51,8 @@ public:
 	            SettingsNotifier& settings_notifier);
 
 	// From Widget:
-	virtual void repaintEvent(dggui::RepaintEvent *repaintEvent) override;
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void repaintEvent(const dggui::RepaintEvent& repaintEvent) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 private:
 	dggui::TexturedBox box{getImageCache(), ":resources/widget.png",
@@ -68,11 +68,11 @@ private:
 		       SettingsNotifier& settings_notifier);
 
 		// From Widget:
-		virtual bool catchMouse() override { return true; }
-		virtual void repaintEvent(dggui::RepaintEvent *repaintEvent) override;
-		virtual void buttonEvent(dggui::ButtonEvent* buttonEvent) override;
-		virtual void mouseMoveEvent(dggui::MouseMoveEvent* mouseMoveEvent) override;
-		virtual void mouseLeaveEvent() override;
+		bool catchMouse() override { return true; }
+		void repaintEvent(const dggui::RepaintEvent& repaintEvent) override;
+		void buttonEvent(const dggui::ButtonEvent& buttonEvent) override;
+		void mouseMoveEvent(const dggui::MouseMoveEvent& mouseMoveEvent) override;
+		void mouseLeaveEvent() override;
 
 	private:
 		Powermap power_map;
diff --git a/plugingui/resamplingframecontent.h b/plugingui/resamplingframecontent.h
index 3bdddc6..758fb63 100644
--- a/plugingui/resamplingframecontent.h
+++ b/plugingui/resamplingframecontent.h
@@ -46,7 +46,7 @@ public:
 	                       SettingsNotifier& settings_notifier);
 
 	// From Widget
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 private:
 	void updateContent();
diff --git a/plugingui/statusframecontent.h b/plugingui/statusframecontent.h
index 55f7a16..123df89 100644
--- a/plugingui/statusframecontent.h
+++ b/plugingui/statusframecontent.h
@@ -44,7 +44,7 @@ public:
 	                   SettingsNotifier& settings_notifier);
 
 	// From Widget
-	virtual void resize(std::size_t width, std::size_t height) override;
+	void resize(std::size_t width, std::size_t height) override;
 
 	void updateContent();
 
diff --git a/plugingui/visualizerframecontent.h b/plugingui/visualizerframecontent.h
index abf54c4..3579f9f 100644
--- a/plugingui/visualizerframecontent.h
+++ b/plugingui/visualizerframecontent.h
@@ -48,8 +48,8 @@ public:
 	VisualizerframeContent(dggui::Widget* parent, Settings& settings,
 	                       SettingsNotifier& settings_notifier);
 
-		// From Widget
-	virtual void resize(std::size_t width, std::size_t height) override;
+	// From Widget
+	void resize(std::size_t width, std::size_t height) override;
 
 private:
 	HumaniserVisualiser visualizer;
diff --git a/test/uitests/framewidgettest.cc b/test/uitests/framewidgettest.cc
index 97f9ed0..9660074 100644
--- a/test/uitests/framewidgettest.cc
+++ b/test/uitests/framewidgettest.cc
@@ -141,7 +141,7 @@ public:
 		return !closing;
 	}
 
-	void repaintEvent(dggui::RepaintEvent* repaintEvent) override
+	void repaintEvent(const dggui::RepaintEvent& repaintEvent) override
 	{
 		dggui::Painter painter(*this);
 		painter.setColour(dggui::Colour(0.85));
diff --git a/test/uitests/powerwidgettest.cc b/test/uitests/powerwidgettest.cc
index 4d01168..fd1346d 100644
--- a/test/uitests/powerwidgettest.cc
+++ b/test/uitests/powerwidgettest.cc
@@ -96,7 +96,7 @@ public:
 		return !closing;
 	}
 
-	void repaintEvent(dggui::RepaintEvent* repaintEvent) override
+	void repaintEvent(const dggui::RepaintEvent& repaintEvent) override
 	{
 		dggui::Painter painter(*this);
 		painter.setColour(dggui::Colour(0.85));
diff --git a/test/uitests/tabwidgettest.cc b/test/uitests/tabwidgettest.cc
index 804e979..ac023fd 100644
--- a/test/uitests/tabwidgettest.cc
+++ b/test/uitests/tabwidgettest.cc
@@ -126,7 +126,7 @@ public:
 		return !closing;
 	}
 
-	void repaintEvent(dggui::RepaintEvent* repaintEvent) override
+	void repaintEvent(const dggui::RepaintEvent& repaintEvent) override
 	{
 		dggui::Painter painter(*this);
 		painter.setColour(dggui::Colour(0.85));