1 files changed, 72 insertions, 0 deletions
diff --git a/src/pinentry/focusframe.cpp b/src/pinentry/focusframe.cpp
new file mode 100644
index 00000000..c0c9f562
--- /dev/null
+++ b/src/pinentry/focusframe.cpp
@@ -0,0 +1,72 @@
+/* focusframe.cpp - A focus indicator for labels.
+ * Copyright (C) 2022 g10 Code GmbH
+ *
+ * Software engineering by Ingo Klöcker <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include "focusframe.h"
+
+#if QT_CONFIG(graphicseffect)
+#include <QGraphicsEffect>
+#endif
+#include <QStyleOptionFocusRect>
+#include <QStylePainter>
+
+static QRect effectiveWidgetRect(const QWidget *w) {
+  // based on QWidgetPrivate::effectiveRectFor
+#if QT_CONFIG(graphicseffect)
+  const auto *const graphicsEffect = w->graphicsEffect();
+  if (graphicsEffect && graphicsEffect->isEnabled())
+    return graphicsEffect->boundingRectFor(w->rect()).toAlignedRect();
+#endif  // QT_CONFIG(graphicseffect)
+  return w->rect();
+}
+
+static QRect clipRect(const QWidget *w) {
+  // based on QWidgetPrivate::clipRect
+  if (!w->isVisible()) {
+    return QRect();
+  }
+  QRect r = effectiveWidgetRect(w);
+  int ox = 0;
+  int oy = 0;
+  while (w && w->isVisible() && !w->isWindow() && w->parentWidget()) {
+    ox -= w->x();
+    oy -= w->y();
+    w = w->parentWidget();
+    r &= QRect(ox, oy, w->width(), w->height());
+  }
+  return r;
+}
+
+void FocusFrame::paintEvent(QPaintEvent *) {
+  if (!widget()) {
+    return;
+  }
+
+  QStylePainter p{this};
+  QStyleOptionFocusRect option;
+  initStyleOption(&option);
+  const int vmargin =
+      style()->pixelMetric(QStyle::PM_FocusFrameVMargin, &option);
+  const int hmargin =
+      style()->pixelMetric(QStyle::PM_FocusFrameHMargin, &option);
+  const QRect rect =
+      clipRect(widget()).adjusted(0, 0, hmargin * 2, vmargin * 2);
+  p.setClipRect(rect);
+  p.drawPrimitive(QStyle::PE_FrameFocusRect, option);
+}