wpa_gui-qt4: Improve scan results signal display

Display signal strength in dBm with visual indicator in the form of a
bar for scan results displayed by wpa_gui-qt4. Any signal > -35dBm is
treated as full signal bar, signals between range of -95<->-35dBm are
displayed linearly. Convert WEXT signal level value to scale that
nl80211 typically reports in dBm. The condition which differentiates
8-bit WEXT dBm and regular dBm is probably fragile, but there is
currently no way to know what the driver is going to report for signal
strength.

Signed-off-by: Kel Modderman <kel@otaku42.de>

wpa_supplicant/wpa_gui-qt4/scanresults.cpp

@@ -15,6 +15,7 @@
 #include <cstdio>
 
 #include "scanresults.h"
+#include "signalbar.h"
 #include "wpagui.h"
 #include "networkconfig.h"
 
@@ -33,6 +34,7 @@ ScanResults::ScanResults(QWidget *parent, const char *, bool, Qt::WFlags)
 	wpagui = NULL;
 	scanResultsWidget->setItemsExpandable(FALSE);
 	scanResultsWidget->setRootIsDecorated(FALSE);
+	scanResultsWidget->setItemDelegate(new SignalBar(scanResultsWidget));
 }
 
 
@@ -91,7 +93,7 @@ void ScanResults::updateResults()
 				bssid = (*it).mid(pos);
 			else if ((*it).startsWith("freq="))
 				freq = (*it).mid(pos);
-			else if ((*it).startsWith("qual="))
+			else if ((*it).startsWith("level="))
 				signal = (*it).mid(pos);
 			else if ((*it).startsWith("flags="))
 				flags = (*it).mid(pos);

wpa_supplicant/wpa_gui-qt4/signalbar.cpp

@@ -0,0 +1,64 @@
+/*
+ * wpa_gui - SignalBar class
+ * Copyright (c) 2011, Kel Modderman <kel@otaku42.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include <cstdio>
+#include <qapplication.h>
+
+#include "signalbar.h"
+
+
+SignalBar::SignalBar(QObject *parent)
+	: QStyledItemDelegate(parent)
+{
+}
+
+
+SignalBar::~SignalBar()
+{
+}
+
+
+void SignalBar::paint(QPainter *painter,
+		      const QStyleOptionViewItem &option,
+		      const QModelIndex &index) const
+{
+	QStyleOptionProgressBar opts;
+	int signal;
+
+	if (index.column() != 3) {
+		QStyledItemDelegate::paint(painter, option, index);
+		return;
+	}
+
+	if (index.data().toInt() > 0)
+		signal = 0 - (256 - index.data().toInt());
+	else
+		signal = index.data().toInt();
+
+	opts.minimum = -95;
+	opts.maximum = -35;
+	if (signal < opts.minimum)
+		opts.progress = opts.minimum;
+	else if (signal > opts.maximum)
+		opts.progress = opts.maximum;
+	else
+		opts.progress = signal;
+
+	opts.text = QString::number(signal) + " dBm";
+	opts.textVisible = true;
+	opts.rect = option.rect;
+
+	QApplication::style()->drawControl(QStyle::CE_ProgressBar,
+					   &opts, painter);
+}

wpa_supplicant/wpa_gui-qt4/signalbar.h

@@ -0,0 +1,34 @@
+/*
+ * wpa_gui - SignalBar class
+ * Copyright (c) 2011, Kel Modderman <kel@otaku42.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#ifndef SIGNALBAR_H
+#define SIGNALBAR_H
+
+#include <QObject>
+#include <QStyledItemDelegate>
+
+class SignalBar : public QStyledItemDelegate
+{
+	Q_OBJECT
+
+public:
+	SignalBar(QObject *parent = 0);
+	~SignalBar();
+
+	virtual void paint(QPainter *painter,
+			   const QStyleOptionViewItem &option,
+			   const QModelIndex &index) const ;
+};
+
+#endif /* SIGNALBAR_H */

wpa_supplicant/wpa_gui-qt4/wpa_gui.pro

@@ -34,6 +34,7 @@ HEADERS	+= wpamsg.h \
 	wpagui.h \
 	eventhistory.h \
 	scanresults.h \
+	signalbar.h \
 	userdatarequest.h \
 	networkconfig.h \
 	addinterface.h \
@@ -44,6 +45,7 @@ SOURCES	+= main.cpp \
 	wpagui.cpp \
 	eventhistory.cpp \
 	scanresults.cpp \
+	signalbar.cpp \
 	userdatarequest.cpp \
 	networkconfig.cpp \
 	addinterface.cpp \