Improve AdapterSetup (#3638)

Use property to set title.
Remove veriable self.dhcpdefault.
Moves the isExistBcmWifi check out of the loop.
Do not allow setting the same nameservers, thx Dima73.
On close remove notifiers to not raise an error when reopening AdapterSetup, thx for report Amai.

lib/python/Screens/NetworkSetup.py

@@ -200,7 +200,7 @@ class AdapterSetup(ConfigListScreen, HelpableScreen, Screen):
 	def __init__(self, session, networkinfo, essid=None):
 		Screen.__init__(self, session)
 		HelpableScreen.__init__(self)
-		self.setTitle(_("Network setup"))
+		self.title = _("Network setup")
 		if isinstance(networkinfo, (list, tuple)):
 			self.iface = networkinfo[0]
 			self.essid = networkinfo[1]
@@ -317,11 +317,7 @@ def createConfig(self):
 		self.dhcpConfigEntry.addNotifier(self.createSetup, initial_call=False)
 		self.ipConfigEntry = NoSave(ConfigIP(default=iNetwork.getAdapterAttribute(self.iface, "ip")) or [0, 0, 0, 0])
 		self.netmaskConfigEntry = NoSave(ConfigIP(default=iNetwork.getAdapterAttribute(self.iface, "netmask") or [255, 0, 0, 0]))
-		if iNetwork.getAdapterAttribute(self.iface, "gateway"):
-			self.dhcpdefault = True
-		else:
-			self.dhcpdefault = False
-		self.hasGatewayConfigEntry = NoSave(ConfigYesNo(default=self.dhcpdefault or False))
+		self.hasGatewayConfigEntry = NoSave(ConfigYesNo(default=iNetwork.getAdapterAttribute(self.iface, "gateway") and True or False))
 		self.hasGatewayConfigEntry.addNotifier(self.createSetup, initial_call=False)
 		self.gatewayConfigEntry = NoSave(ConfigIP(default=iNetwork.getAdapterAttribute(self.iface, "gateway") or [0, 0, 0, 0]))
 		nameserver = (iNetwork.getIfaceNameservers(self.iface) + [[0, 0, 0, 0]] * 2)[:2]
@@ -343,14 +339,14 @@ def createSetup(self, element=None):
 
 			self.extended = None
 			self.configStrings = None
+			isExistBcmWifi = os.path.exists("/tmp/bcm/" + self.iface)
 			for p in plugins.getPlugins(PluginDescriptor.WHERE_NETWORKSETUP):
 				call_fnc = p.fnc["ifaceSupported"](self.iface)
 				if call_fnc is not None:
 					if "WlanPluginEntry" in p.fnc:  # internally used only for WLAN Plugin
 						self.extended = call_fnc
 						if "configStrings" in p.fnc:
 							self.configStrings = p.fnc["configStrings"]
-						isExistBcmWifi = os.path.exists("/tmp/bcm/" + self.iface)
 						if not isExistBcmWifi:
 							self.list.append((_("Hidden network"), config.plugins.wlan.hiddenessid))
 						self.wlanSSID = (_("Network name (SSID)"), config.plugins.wlan.essid)
@@ -425,7 +421,7 @@ def applyConfig(self, ret=False):
 			dns = []
 			if self.primaryDNS.value != [0, 0, 0, 0]:
 				dns.append(self.primaryDNS.value)
-			if self.secondaryDNS.value != [0, 0, 0, 0]:
+			if self.secondaryDNS.value != [0, 0, 0, 0] and self.secondaryDNS.value not in dns:
 				dns.append(self.secondaryDNS.value)
 			iNetwork.setAdapterAttribute(self.iface, "dns-nameservers", dns)
 			if self.extended is not None and self.configStrings is not None:
@@ -496,6 +492,10 @@ def runAsync(self, finished_cb):
 
 	def cleanup(self):
 		iNetwork.stopLinkStateConsole()
+		config.plugins.wlan.encryption.removeNotifier(self.createSetup)
+		self.activateInterfaceEntry.removeNotifier(self.createSetup)
+		self.dhcpConfigEntry.removeNotifier(self.createSetup)
+		self.hasGatewayConfigEntry.removeNotifier(self.createSetup)
 
 	def hideInputHelp(self):
 		current = self["config"].getCurrent()