Merge pull request #620 from ispyisail/fix/element-panel-dark-theme

Fix element library icons invisible on dark OS themes

sources/ElementsCollection/elementstreeview.cpp

@@ -43,6 +43,14 @@ ElementsTreeView::ElementsTreeView(QWidget *parent) :
 {
 	// force du noir sur une alternance de blanc (comme le schema) et de gris
 	// clair, avec du blanc sur bleu pas trop fonce pour la selection
+	//
+	// Element icons are rendered with colors read directly from each .elmt
+	// file (almost always black linework, matching printed-schematic
+	// convention) onto a transparent background -- so this view must keep
+	// a light background regardless of the OS/desktop theme, or the icons
+	// become invisible on dark themes. QAbstractItemView paints its rows
+	// using the viewport's palette, not the view's own, so the palette
+	// must be applied to both to actually take effect under every style.
 	QPalette qp = palette();
 	qp.setColor(QPalette::Text,            Qt::black);
 	qp.setColor(QPalette::Base,            Qt::white);
@@ -50,6 +58,7 @@ ElementsTreeView::ElementsTreeView(QWidget *parent) :
 	qp.setColor(QPalette::Highlight,       QColor("#678db2"));
 	qp.setColor(QPalette::HighlightedText, Qt::black);
 	setPalette(qp);
+	viewport()->setPalette(qp);
 }
 
 /**

sources/elementspanel.cpp

@@ -56,6 +56,14 @@ ElementsPanel::ElementsPanel(QWidget *parent) :
 	
 	// force du noir sur une alternance de blanc (comme le schema) et de gris
 	// clair, avec du blanc sur bleu pas trop fonce pour la selection
+	//
+	// Element icons are rendered with colors read directly from each .elmt
+	// file (almost always black linework, matching printed-schematic
+	// convention) onto a transparent background -- so this view must keep
+	// a light background regardless of the OS/desktop theme, or the icons
+	// become invisible on dark themes. QAbstractItemView paints its rows
+	// using the viewport's palette, not the view's own, so the palette
+	// must be applied to both to actually take effect under every style.
 	QPalette qp = palette();
 	qp.setColor(QPalette::Text,            Qt::black);
 	qp.setColor(QPalette::Base,            Qt::white);
@@ -63,6 +71,7 @@ ElementsPanel::ElementsPanel(QWidget *parent) :
 	qp.setColor(QPalette::Highlight,       QColor("#678db2"));
 	qp.setColor(QPalette::HighlightedText, Qt::black);
 	setPalette(qp);
+	viewport()->setPalette(qp);
 	
 		// we handle double click on items ourselves
 	connect(this, &ElementsPanel::itemDoubleClicked, this, &ElementsPanel::slot_doubleClick);