Merge pull request #210 from OpenVicProject/gui-listbox

Add GUIListBox + UI improvements

1 files changed, 226 insertions, 0 deletions

diff --git a/extension/src/openvic-extension/classes/GUIListBox.cpp b/extension/src/openvic-extension/classes/GUIListBox.cpp
new file mode 100644
index 0000000..f7b8d88
--- /dev/null
+++ b/extension/src/openvic-extension/classes/GUIListBox.cpp
@@ -0,0 +1,226 @@
+#include "GUIListBox.hpp"
+
+#include <godot_cpp/classes/input_event_mouse_button.hpp>
+#include <godot_cpp/variant/utility_functions.hpp>
+
+#include "openvic-extension/utility/ClassBindings.hpp"
+#include "openvic-extension/utility/UITools.hpp"
+#include "openvic-extension/utility/Utilities.hpp"
+
+using namespace OpenVic;
+using namespace godot;
+
+using OpenVic::Utilities::std_view_to_godot_string;
+
+Error GUIListBox::_calculate_child_arrangement() {
+	ERR_FAIL_NULL_V(gui_listbox, FAILED);
+
+	const int32_t child_count = get_child_count();
+	const real_t max_height = get_size().height;
+
+	real_t height = 0.0f, height_under_max_scroll_index = 0.0f;
+
+	children_data.clear();
+	max_scroll_index = 0;
+
+	for (int32_t index = 0; index < child_count; ++index) {
+		Control* child = Object::cast_to<Control>(get_child(index));
+		if (child != nullptr && child != scrollbar && child->is_visible()) {
+			const real_t child_height = child->get_size().height; /* Spacing is ignored */
+			children_data.push_back({ child, height, child_height });
+
+			height += child_height;
+			height_under_max_scroll_index += child_height;
+
+			while (height_under_max_scroll_index > max_height && max_scroll_index + 1 < children_data.size()) {
+				height_under_max_scroll_index -= children_data[max_scroll_index++].height;
+			}
+		}
+	}
+
+	ERR_FAIL_NULL_V(scrollbar, FAILED);
+
+	scrollbar->set_limits(0, max_scroll_index, false);
+	scrollbar->emit_value_changed();
+	scrollbar->set_visible(max_scroll_index > 0);
+
+	return OK;
+}
+
+Error GUIListBox::_update_child_positions() {
+	ERR_FAIL_NULL_V(gui_listbox, FAILED);
+
+	if (children_data.empty()) {
+		return OK;
+	}
+
+	const real_t max_height = get_size().height;
+	const real_t scroll_pos = children_data[scroll_index].start_pos;
+
+	for (int32_t index = 0; index < children_data.size(); ++index) {
+		child_data_t const& data = children_data[index];
+		if (index < scroll_index || data.start_pos + data.height > scroll_pos + max_height) {
+			data.child->set_position({ 0.0f, max_height + 10.0f });
+		} else {
+			data.child->set_position({ 0.0f, data.start_pos - scroll_pos });
+		}
+	}
+
+	return OK;
+}
+
+void GUIListBox::_bind_methods() {
+	OV_BIND_METHOD(GUIListBox::clear);
+	OV_BIND_METHOD(GUIListBox::clear_children);
+
+	OV_BIND_METHOD(GUIListBox::get_scroll_index);
+	OV_BIND_METHOD(GUIListBox::set_scroll_index, { "new_scroll_index" });
+	OV_BIND_METHOD(GUIListBox::get_max_scroll_index);
+
+	OV_BIND_METHOD(GUIListBox::get_gui_listbox_name);
+	OV_BIND_METHOD(GUIListBox::get_scrollbar);
+}
+
+void GUIListBox::_notification(int what) {
+	switch (what) {
+	case NOTIFICATION_SORT_CHILDREN: {
+		_calculate_child_arrangement();
+	} break;
+	}
+}
+
+GUIListBox::GUIListBox()
+  : gui_listbox { nullptr }, scrollbar { nullptr }, children_data {}, scroll_index { 0 }, max_scroll_index { 0 } {
+	set_clip_contents(true);
+}
+
+Vector2 GUIListBox::_get_minimum_size() const {
+	if (gui_listbox != nullptr) {
+		Size2 size = Utilities::to_godot_fvec2(gui_listbox->get_size());
+
+		if (scrollbar != nullptr) {
+			size.width += scrollbar->get_minimum_size().width;
+		}
+
+		return size;
+	} else {
+		return {};
+	}
+}
+
+void GUIListBox::_gui_input(godot::Ref<godot::InputEvent> const& event) {
+	ERR_FAIL_NULL(event);
+
+	Ref<InputEventMouseButton> mb = event;
+
+	if (mb.is_valid()) {
+		if (mb->is_pressed()) {
+			if (mb->get_button_index() == MouseButton::MOUSE_BUTTON_WHEEL_UP) {
+				set_scroll_index(scroll_index - 1);
+			} else if (mb->get_button_index() == MouseButton::MOUSE_BUTTON_WHEEL_DOWN) {
+				set_scroll_index(scroll_index + 1);
+			} else {
+				return;
+			}
+			accept_event();
+		}
+	}
+}
+
+void GUIListBox::clear() {
+	gui_listbox = nullptr;
+	children_data.clear();
+	scroll_index = 0;
+	max_scroll_index = 0;
+	clear_children();
+	if (scrollbar != nullptr) {
+		remove_child(scrollbar);
+		scrollbar = nullptr;
+	}
+}
+
+void GUIListBox::clear_children() {
+	int32_t child_count = get_child_count();
+	while (child_count > 0) {
+		Node* child = get_child(--child_count);
+		if (child != scrollbar) {
+			remove_child(child);
+		}
+	}
+	if (scrollbar != nullptr) {
+		scrollbar->set_value(0);
+	}
+}
+
+void GUIListBox::set_scroll_index(int32_t new_scroll_index) {
+	scroll_index = std::clamp(new_scroll_index, 0, max_scroll_index);
+	if (scrollbar != nullptr && scrollbar->get_value() != scroll_index) {
+		scrollbar->set_value(scroll_index, false);
+	}
+	_update_child_positions();
+}
+
+Error GUIListBox::set_gui_listbox(GUI::ListBox const* new_gui_listbox) {
+	if (gui_listbox == new_gui_listbox) {
+		return OK;
+	}
+
+	if (new_gui_listbox == nullptr) {
+		clear();
+		return OK;
+	}
+
+	gui_listbox = new_gui_listbox;
+
+	const String scrollbar_name = std_view_to_godot_string(gui_listbox->get_scrollbar_name());
+
+	Error err = OK;
+
+	if (scrollbar_name.is_empty()) {
+		UtilityFunctions::push_error("GUIListBox ", get_name(), " has no scrollbar name!");
+		err = FAILED;
+		scrollbar = nullptr;
+	} else {
+		static const String scrollbar_scene = "core";
+
+		Control* scrollbar_control = nullptr;
+		if (!UITools::generate_gui_element(scrollbar_scene, scrollbar_name, "", scrollbar_control)) {
+			UtilityFunctions::push_error("Error generating scrollbar ", scrollbar_name, " for GUIListBox ", get_name());
+			err = FAILED;
+		}
+
+		if (scrollbar_control != nullptr) {
+			scrollbar = Object::cast_to<GUIScrollbar>(scrollbar_control);
+			if (scrollbar != nullptr) {
+				add_child(scrollbar);
+
+				const Size2 size = Utilities::to_godot_fvec2(gui_listbox->get_size());
+				scrollbar->set_position({ size.width, 0.0f });
+				scrollbar->set_length_override(size.height);
+
+				static const StringName set_scroll_index_func_name = "set_scroll_index";
+
+				scrollbar->connect(
+					GUIScrollbar::signal_value_changed(), Callable { this, set_scroll_index_func_name }, CONNECT_PERSIST
+				);
+			} else {
+				UtilityFunctions::push_error(
+					"Element ", scrollbar_name, " for GUIListBox ", get_name(), " is not a GUIScrollbar"
+				);
+				err = FAILED;
+			}
+		} else {
+			scrollbar = nullptr;
+		}
+	}
+
+	return err;
+}
+
+String GUIListBox::get_gui_listbox_name() const {
+	return gui_listbox != nullptr ? std_view_to_godot_string(gui_listbox->get_name()) : String {};
+}
+
+GUIScrollbar* GUIListBox::get_scrollbar() const {
+	return scrollbar;
+}