ui: Black and white size grips for dialog windows

src/lib_gui/qt/window/QtAbout.cpp

@@ -13,6 +13,7 @@
 QtAbout::QtAbout(QWidget *parent)
 	: QtWindow(parent)
 {
+	setSizeGripStyle(false);
 }
 
 QSize QtAbout::sizeHint() const

src/lib_gui/qt/window/QtIndexingDialog.cpp

@@ -25,6 +25,7 @@ QtIndexingDialog::QtIndexingDialog(QWidget* parent)
 	, m_callback([](bool){})
 {
 	// setWindowFlags(Qt::WindowStaysOnTopHint);
+	setSizeGripStyle(false);
 }
 
 QSize QtIndexingDialog::sizeHint() const

src/lib_gui/qt/window/QtWindow.cpp

@@ -55,16 +55,10 @@ QtWindow::QtWindow(QWidget* parent)
 	layout->addWidget(m_content);
 
 	QHBoxLayout* gripLayout = new QHBoxLayout();
-	QSizeGrip* sizeGrip = new QSizeGrip(m_window);
-	sizeGrip->setStyleSheet(QString::fromStdString(
-		"QSizeGrip {"
-		"	max-height: 12px;"
-		"	max-width: 12px;"
-		"	border-image: url(" + ResourcePaths::getGuiPath() + "window/size_grip.png);"
-		"}"
-	));
+	m_sizeGrip = new QSizeGrip(m_window);
+	setSizeGripStyle(true);
 	gripLayout->addWidget(new QWidget());
-	gripLayout->addWidget(sizeGrip);
+	gripLayout->addWidget(m_sizeGrip);
 	layout->addLayout(gripLayout);
 
 	resize(sizeHint());
@@ -143,6 +137,19 @@ void QtWindow::setup()
 	setupDone();
 }
 
+void QtWindow::setSizeGripStyle(bool isBlack)
+{
+	std::string path = isBlack ? "size_grip_black.png" : "size_grip_white.png";
+
+	m_sizeGrip->setStyleSheet(QString::fromStdString(
+		"QSizeGrip {"
+		"	max-height: 16px;"
+		"	max-width: 16px;"
+		"	border-image: url(" + ResourcePaths::getGuiPath() + "window/" + path + ");"
+		"}"
+	));
+}
+
 void QtWindow::setCancelAble(bool cancelable)
 {
 	setCloseEnabled(cancelable);

src/lib_gui/qt/window/QtWindow.h

@@ -24,6 +24,8 @@ public:
 
 	void setup();
 
+	void setSizeGripStyle(bool isBlack);
+
 	void setCancelAble(bool cancelAble);
 	void setScrollAble(bool scrollAble);