fix critical segmentation fault, and implemented hiding main_window when about_window is opened to improve UX

Author: Reim-developer

src/front_end/about_widget.cxx

@@ -3,6 +3,7 @@
 #include <qdebug.h>
 #include <qgridlayout.h>
 #include <qlogging.h>
+#include <qmainwindow.h>
 #include <qobject.h>
 #include <qpushbutton.h>
 
@@ -17,19 +18,23 @@ using Self = AboutWidget;
 AboutWidget::AboutWidget() { show_about = make_unique<QPushButton>(); }
 
 void Self::setup_event() {
-	const auto function = [this]() {
-		if (!about_window) {
-			about_window = make_unique<AboutWindow>();
-		}
+	about_window = make_unique<AboutWindow>();
 
+	// clang-format off
+	const auto function = [this]() {
 		about_window->show_window();
-	};
+	};	// clang-format on
 
 	QObject::connect(show_about.get(), &QPushButton::clicked, function);
 }
 
 void Self::setup_widget(QGridLayout *grid_layout) {
 	show_about->setText("About");
-	this->setup_event();
 	grid_layout->addWidget(show_about.get(), 1, 1);
+
+	this->setup_event();
+}
+
+void Self::setup_about_window_event(QMainWindow *main_window) {
+	about_window->on_about_window_event(main_window);
 }

src/front_end/about_window.cxx

@@ -3,6 +3,7 @@
 #include <qdialog.h>
 #include <qgridlayout.h>
 #include <qlogging.h>
+#include <qmainwindow.h>
 #include <qmessagebox.h>
 #include <qobject.h>
 #include <qpushbutton.h>
@@ -15,8 +16,16 @@ using Lazyboard::front_end::AboutWindow;
 using std::make_unique;
 using Self = AboutWindow;
 
+#if defined(LAZY_DEBUG)
+	#include <string>
+
+	#include "../front_end_utils/include/utils.hxx"
+using Lazyboard::front_end_utils::debug_info;
+using Lazyboard::front_end_utils::dump_ptr_address;
+using std::string;
+#endif
+
 AboutWindow::AboutWindow() {
-	about_window = make_unique<QDialog>();
 	grid_layout = make_unique<QGridLayout>();
 	github_button = make_unique<QPushButton>();
 	github_issue_button = make_unique<QPushButton>();
@@ -31,8 +40,7 @@ void Self::is_open_browser_ok(ResultContext &status) {
 			break;
 
 		case R::FAILED:
-			QMessageBox::critical(about_window.get(), "Error",
-								  "Could not open your browser");
+			QMessageBox::critical(this, "Error", "Could not open your browser");
 	}
 }
 
@@ -66,14 +74,48 @@ void Self::setup_buttons() {
 }
 
 void Self::setup_front_end() {
-	about_window->setLayout(this->grid_layout.get());
+	this->setLayout(this->grid_layout.get());
 	this->setup_buttons();
 }
 
 void Self::show_window() {
-	about_window->setMinimumSize(MIN_WIDTH, MIN_HEIGHT);
-	about_window->setWindowTitle("Lazyboard About");
+	this->setMinimumSize(MIN_WIDTH, MIN_HEIGHT);
+	this->setWindowTitle("Lazyboard About");
 
 	this->setup_front_end();
-	about_window->exec();
+	this->exec();
+}
+
+void Self::on_closed(QMainWindow *main_window) {
+	using O = QObject;
+	const auto fn = [this, main_window] {
+		main_window->show();
+
+		// clang-format off
+		#if defined (LAZY_DEBUG)
+			debug_info("About window is closed");
+		#endif	// clang-format on
+	};
+
+	O::connect(this, &QDialog::rejected, fn);
+}
+
+void Self::showEvent(QShowEvent *event) {
+	QDialog::showEvent(event);
+	this->_main_window->setHidden(true);
+
+	// clang-format off
+	#if defined (LAZY_DEBUG)
+		debug_info("About Dialog is open");
+	#endif	// clang-format on
+}
+
+void Self::on_about_window_event(QMainWindow *main_window) {
+	this->_main_window = main_window;
+	this->on_closed(this->_main_window);
+
+	// clang-format off
+	#if defined (LAZY_DEBUG) 
+		dump_ptr_address(main_window);
+	#endif	// clang-format on
 }

src/front_end/include/about_widget.hxx

@@ -2,6 +2,7 @@
 #define ABOUT_WIDGET_HXX
 
 #include <qgridlayout.h>
+#include <qmainwindow.h>
 #include <qpushbutton.h>
 
 #include <memory>
@@ -24,6 +25,7 @@ class AboutWidget {
 
    public:
 	void setup_widget(QGridLayout *layout);
+	void setup_about_window_event(QMainWindow *main_window);
 };
 
 }  // namespace Lazyboard::front_end

src/front_end/include/about_window.hxx

@@ -3,6 +3,7 @@
 
 #include <qdialog.h>
 #include <qgridlayout.h>
+#include <qmainwindow.h>
 #include <qpushbutton.h>
 
 #include <memory>
@@ -11,9 +12,8 @@
 using std::unique_ptr;
 
 namespace Lazyboard::front_end {
-class AboutWindow {
+class AboutWindow : public QDialog {
    private:
-	unique_ptr<QDialog> about_window;
 	unique_ptr<QGridLayout> grid_layout;
 	unique_ptr<QPushButton> github_button;
 	unique_ptr<QPushButton> github_issue_button;
@@ -28,17 +28,25 @@ class AboutWindow {
 	const char *GITHUB_PULL_URL =
 		"https://github.com/reim-developer/zClipboard/pulls";
 
+   private:
+	QMainWindow *_main_window = nullptr;
+
+   protected:
+	void showEvent(QShowEvent *event) override;
+
    private:
 	void is_open_browser_ok(ResultContext &status);
 	void open_browser_when_clicked(QPushButton *button, const char *url);
 
    private:
 	void setup_front_end();
 	void setup_buttons();
+	void on_closed(QMainWindow *main_window);
 
    public:
 	AboutWindow();
 	void show_window();
+	void on_about_window_event(QMainWindow *main_window);
 };
 }  // namespace Lazyboard::front_end
 

src/front_end/main_window.cxx

@@ -55,5 +55,7 @@ void Self::front_end_show() {
 
 	table_widget->setup_widget(this->grid_layout);
 	setting_widget->setup_widget(this->grid_layout);
+
 	about_widget->setup_widget(this->grid_layout);
+	about_widget->setup_about_window_event(main_window.get());
 }

src/front_end/table_widget.cxx

@@ -3,6 +3,7 @@
 #include <qabstractitemview.h>
 #include <qgridlayout.h>
 #include <qheaderview.h>
+#include <qmainwindow.h>
 #include <qtableview.h>
 #include <qtablewidget.h>
 

src/front_end_utils/include/utils.hxx

@@ -11,6 +11,7 @@
 
 #include <algorithm>
 #include <initializer_list>
+#include <string>
 #include <type_traits>
 #include <utility>
 #include <vector>
@@ -22,6 +23,7 @@ using std::for_each;
 using std::forward;
 using std::initializer_list;
 using std::is_same_v;
+using std::string;
 using std::stringstream;
 using std::vector;
 
@@ -34,9 +36,9 @@ using std::source_location;
 
 namespace Lazyboard::front_end_utils {
 template <typename T>
-concept is_qcolor = requires(const T& t) { QColor(t); };
+concept qcolor_bound = requires(const T& t) { QColor(t); };
 
-template <is_qcolor... Args>
+template <qcolor_bound... Args>
 inline constexpr bool is_valid_hex_color(Args&&... args) noexcept {
 	return (... && [&]() {
 		QColor color(std::forward<Args>(args));
@@ -91,11 +93,11 @@ inline void dump_ptr_address(T* t,
 }
 
 template <typename T>
-concept string_bound = requires(const T& t) { string(t); };
+concept string_bound = requires(const T& t) { std::string(t); };
 
 template <typename string_bound>
 inline void debug_info(string_bound&& information) {
-	auto info = forward<string_bound>(information);
+	auto info = std::forward<string_bound>(information);
 
 	println("{}[INFO_DEBUG]{} {}", green, white, info);
 }