ui: improve error handling

Signed-off-by: Alexander Neumann <an2048@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

ui/aboutdialog.go

@@ -20,11 +20,22 @@ import (
 var easterEggIndex = -1
 
 func onAbout(owner walk.Form) {
+	showError(runAboutDialog(owner), owner)
+}
+
+func runAboutDialog(owner walk.Form) error {
 	vbl := walk.NewVBoxLayout()
 	vbl.SetMargins(walk.Margins{80, 20, 80, 20})
 	vbl.SetSpacing(10)
 
-	dlg, _ := walk.NewDialogWithFixedSize(owner)
+	var disposables walk.Disposables
+	defer disposables.Treat()
+
+	dlg, err := walk.NewDialogWithFixedSize(owner)
+	if err != nil {
+		return err
+	}
+	disposables.Add(dlg)
 	dlg.SetTitle("About WireGuard")
 	dlg.SetLayout(vbl)
 	if icon, err := loadLogoIcon(32); err == nil {
@@ -34,7 +45,10 @@ func onAbout(owner walk.Form) {
 	font, _ := walk.NewFont("Segoe UI", 9, 0)
 	dlg.SetFont(font)
 
-	iv, _ := walk.NewImageView(dlg)
+	iv, err := walk.NewImageView(dlg)
+	if err != nil {
+		return err
+	}
 	iv.SetCursor(walk.CursorHand())
 	iv.MouseUp().Attach(func(x, y int, button walk.MouseButton) {
 		if button == walk.LeftButton {
@@ -55,34 +69,52 @@ func onAbout(owner walk.Form) {
 		iv.SetImage(logo)
 	}
 
-	wgLbl, _ := walk.NewTextLabel(dlg)
+	wgLbl, err := walk.NewTextLabel(dlg)
+	if err != nil {
+		return err
+	}
 	wgFont, _ := walk.NewFont("Segoe UI", 16, walk.FontBold)
 	wgLbl.SetFont(wgFont)
 	wgLbl.SetTextAlignment(walk.AlignHCenterVNear)
 	wgLbl.SetText("WireGuard")
 
-	detailsLbl, _ := walk.NewTextLabel(dlg)
+	detailsLbl, err := walk.NewTextLabel(dlg)
+	if err != nil {
+		return err
+	}
 	detailsLbl.SetTextAlignment(walk.AlignHCenterVNear)
 	detailsLbl.SetText(fmt.Sprintf("App version: %s\nGo backend version: %s\nGo version: %s\nOperating system: %s\nArchitecture: %s", version.RunningVersion(), device.WireGuardGoVersion, strings.TrimPrefix(runtime.Version(), "go"), version.OsName(), runtime.GOARCH))
 
-	copyrightLbl, _ := walk.NewTextLabel(dlg)
+	copyrightLbl, err := walk.NewTextLabel(dlg)
+	if err != nil {
+		return err
+	}
 	copyrightFont, _ := walk.NewFont("Segoe UI", 7, 0)
 	copyrightLbl.SetFont(copyrightFont)
 	copyrightLbl.SetTextAlignment(walk.AlignHCenterVNear)
 	copyrightLbl.SetText("Copyright © 2015-2019 Jason A. Donenfeld. All Rights Reserved.")
 
-	buttonCP, _ := walk.NewComposite(dlg)
+	buttonCP, err := walk.NewComposite(dlg)
+	if err != nil {
+		return err
+	}
 	hbl := walk.NewHBoxLayout()
 	hbl.SetMargins(walk.Margins{VNear: 10})
 	buttonCP.SetLayout(hbl)
 	walk.NewHSpacer(buttonCP)
-	closePB, _ := walk.NewPushButton(buttonCP)
+	closePB, err := walk.NewPushButton(buttonCP)
+	if err != nil {
+		return err
+	}
 	closePB.SetAlignment(walk.AlignHCenterVNear)
 	closePB.SetText("Close")
 	closePB.Clicked().Attach(func() {
 		dlg.Accept()
 	})
-	donatePB, _ := walk.NewPushButton(buttonCP)
+	donatePB, err := walk.NewPushButton(buttonCP)
+	if err != nil {
+		return err
+	}
 	donatePB.SetAlignment(walk.AlignHCenterVNear)
 	donatePB.SetText("♥ Donate!")
 	donatePB.Clicked().Attach(func() {
@@ -97,5 +129,9 @@ func onAbout(owner walk.Form) {
 	dlg.SetDefaultButton(donatePB)
 	dlg.SetCancelButton(closePB)
 
+	disposables.Spare()
+
 	dlg.Run()
+
+	return nil
 }

ui/confview.go

@@ -98,25 +98,46 @@ func (lsl *labelStatusLine) update(state manager.TunnelState) {
 	lsl.statusLabel.SetTextSelection(s, e)
 }
 
-func newLabelStatusLine(parent walk.Container) *labelStatusLine {
+func (lsl *labelStatusLine) Dispose() {
+	lsl.label.Dispose()
+	lsl.statusComposite.Dispose()
+}
+
+func newLabelStatusLine(parent walk.Container) (*labelStatusLine, error) {
+	var err error
+	var disposables walk.Disposables
+	defer disposables.Treat()
+
 	lsl := new(labelStatusLine)
 
-	lsl.label, _ = walk.NewTextLabel(parent)
+	if lsl.label, err = walk.NewTextLabel(parent); err != nil {
+		return nil, err
+	}
+	disposables.Add(lsl.label)
 	lsl.label.SetText("Status:")
 	lsl.label.SetTextAlignment(walk.AlignHFarVNear)
 
-	lsl.statusComposite, _ = walk.NewComposite(parent)
+	if lsl.statusComposite, err = walk.NewComposite(parent); err != nil {
+		return nil, err
+	}
+	disposables.Add(lsl.statusComposite)
 	layout := walk.NewHBoxLayout()
 	layout.SetMargins(walk.Margins{})
 	layout.SetAlignment(walk.AlignHNearVNear)
 	layout.SetSpacing(0)
 	lsl.statusComposite.SetLayout(layout)
 
-	lsl.statusImage, _ = walk.NewImageView(lsl.statusComposite)
+	if lsl.statusImage, err = walk.NewImageView(lsl.statusComposite); err != nil {
+		return nil, err
+	}
+	disposables.Add(lsl.statusImage)
 	lsl.statusImage.SetMargin(2)
 	lsl.statusImage.SetMode(walk.ImageViewModeIdeal)
 
-	lsl.statusLabel, _ = walk.NewLineEdit(lsl.statusComposite)
+	if lsl.statusLabel, err = walk.NewLineEdit(lsl.statusComposite); err != nil {
+		return nil, err
+	}
+	disposables.Add(lsl.statusLabel)
 	win.SetWindowLong(lsl.statusLabel.Handle(), win.GWL_EXSTYLE, win.GetWindowLong(lsl.statusLabel.Handle(), win.GWL_EXSTYLE)&^win.WS_EX_CLIENTEDGE)
 	lsl.statusLabel.SetReadOnly(true)
 	lsl.statusLabel.SetBackground(walk.NullBrush())
@@ -125,7 +146,9 @@ func newLabelStatusLine(parent walk.Container) *labelStatusLine {
 	})
 	lsl.update(manager.TunnelUnknown)
 
-	return lsl
+	disposables.Spare()
+
+	return lsl, nil
 }
 
 func (lt *labelTextLine) widgets() (walk.Widget, walk.Widget) {
@@ -146,14 +169,30 @@ func (lt *labelTextLine) hide() {
 	lt.text.SetVisible(false)
 }
 
-func newLabelTextLine(fieldName string, parent walk.Container) *labelTextLine {
+func (lt *labelTextLine) Dispose() {
+	lt.label.Dispose()
+	lt.text.Dispose()
+}
+
+func newLabelTextLine(fieldName string, parent walk.Container) (*labelTextLine, error) {
+	var err error
+	var disposables walk.Disposables
+	defer disposables.Treat()
+
 	lt := new(labelTextLine)
-	lt.label, _ = walk.NewTextLabel(parent)
+
+	if lt.label, err = walk.NewTextLabel(parent); err != nil {
+		return nil, err
+	}
+	disposables.Add(lt.label)
 	lt.label.SetText(fieldName + ":")
 	lt.label.SetTextAlignment(walk.AlignHFarVNear)
 	lt.label.SetVisible(false)
 
-	lt.text, _ = walk.NewTextEdit(parent)
+	if lt.text, err = walk.NewTextEdit(parent); err != nil {
+		return nil, err
+	}
+	disposables.Add(lt.text)
 	win.SetWindowLong(lt.text.Handle(), win.GWL_EXSTYLE, win.GetWindowLong(lt.text.Handle(), win.GWL_EXSTYLE)&^win.WS_EX_CLIENTEDGE)
 	lt.text.SetCompactHeight(true)
 	lt.text.SetReadOnly(true)
@@ -162,7 +201,10 @@ func newLabelTextLine(fieldName string, parent walk.Container) *labelTextLine {
 	lt.text.FocusedChanged().Attach(func() {
 		lt.text.SetTextSelection(0, 0)
 	})
-	return lt
+
+	disposables.Spare()
+
+	return lt, nil
 }
 
 func (tal *toggleActiveLine) widgets() (walk.Widget, walk.Widget) {
@@ -191,67 +233,121 @@ func (tal *toggleActiveLine) update(state manager.TunnelState) {
 	tal.button.SetVisible(state != manager.TunnelUnknown)
 }
 
-func newToggleActiveLine(parent walk.Container) *toggleActiveLine {
+func (tal *toggleActiveLine) Dispose() {
+	tal.composite.Dispose()
+}
+
+func newToggleActiveLine(parent walk.Container) (*toggleActiveLine, error) {
+	var err error
+	var disposables walk.Disposables
+	defer disposables.Treat()
+
 	tal := new(toggleActiveLine)
 
-	tal.composite, _ = walk.NewComposite(parent)
+	if tal.composite, err = walk.NewComposite(parent); err != nil {
+		return nil, err
+	}
+	disposables.Add(tal.composite)
 	layout := walk.NewHBoxLayout()
 	layout.SetMargins(walk.Margins{0, 0, 0, 6})
 	tal.composite.SetLayout(layout)
 
-	tal.button, _ = walk.NewPushButton(tal.composite)
+	if tal.button, err = walk.NewPushButton(tal.composite); err != nil {
+		return nil, err
+	}
+	disposables.Add(tal.button)
 	walk.NewHSpacer(tal.composite)
 	tal.update(manager.TunnelStopped)
 
-	return tal
+	disposables.Spare()
+
+	return tal, nil
 }
 
-func newInterfaceView(parent walk.Container) *interfaceView {
-	iv := &interfaceView{
-		newLabelStatusLine(parent),
-		newLabelTextLine("Public key", parent),
-		newLabelTextLine("Listen port", parent),
-		newLabelTextLine("MTU", parent),
-		newLabelTextLine("Addresses", parent),
-		newLabelTextLine("DNS servers", parent),
-		newToggleActiveLine(parent),
-		nil,
+type labelTextLineItem struct {
+	label string
+	ptr   **labelTextLine
+}
+
+func createLabelTextLines(items []labelTextLineItem, parent walk.Container, disposables *walk.Disposables) ([]widgetsLine, error) {
+	var err error
+	var disps walk.Disposables
+	defer disps.Treat()
+
+	wls := make([]widgetsLine, len(items))
+	for i, item := range items {
+		if *item.ptr, err = newLabelTextLine(item.label, parent); err != nil {
+			return nil, err
+		}
+		disps.Add(*item.ptr)
+		if disposables != nil {
+			disposables.Add(*item.ptr)
+		}
+		wls[i] = *item.ptr
 	}
-	iv.lines = []widgetsLine{
-		iv.status,
-		iv.publicKey,
-		iv.listenPort,
-		iv.mtu,
-		iv.addresses,
-		iv.dns,
-		iv.toggleActive,
+
+	disps.Spare()
+
+	return wls, nil
+}
+
+func newInterfaceView(parent walk.Container) (*interfaceView, error) {
+	var err error
+	var disposables walk.Disposables
+	defer disposables.Treat()
+
+	iv := new(interfaceView)
+
+	if iv.status, err = newLabelStatusLine(parent); err != nil {
+		return nil, err
 	}
+	disposables.Add(iv.status)
+
+	items := []labelTextLineItem{
+		{"Public key", &iv.publicKey},
+		{"Listen port", &iv.listenPort},
+		{"MTU", &iv.mtu},
+		{"Addresses", &iv.addresses},
+		{"DNS servers", &iv.dns},
+	}
+	if iv.lines, err = createLabelTextLines(items, parent, &disposables); err != nil {
+		return nil, err
+	}
+
+	if iv.toggleActive, err = newToggleActiveLine(parent); err != nil {
+		return nil, err
+	}
+	disposables.Add(iv.toggleActive)
+
+	iv.lines = append([]widgetsLine{iv.status}, append(iv.lines, iv.toggleActive)...)
+
 	layoutInGrid(iv, parent.Layout().(*walk.GridLayout))
-	return iv
+
+	disposables.Spare()
+
+	return iv, nil
 }
 
-func newPeerView(parent walk.Container) *peerView {
-	pv := &peerView{
-		newLabelTextLine("Public key", parent),
-		newLabelTextLine("Preshared key", parent),
-		newLabelTextLine("Allowed IPs", parent),
-		newLabelTextLine("Endpoint", parent),
-		newLabelTextLine("Persistent keepalive", parent),
-		newLabelTextLine("Latest handshake", parent),
-		newLabelTextLine("Transfer", parent),
-		nil,
+func newPeerView(parent walk.Container) (*peerView, error) {
+	pv := new(peerView)
+
+	items := []labelTextLineItem{
+		{"Public key", &pv.publicKey},
+		{"Preshared key", &pv.presharedKey},
+		{"Allowed IPs", &pv.allowedIPs},
+		{"Endpoint", &pv.endpoint},
+		{"Persistent keepalive", &pv.persistentKeepalive},
+		{"Latest handshake", &pv.latestHandshake},
+		{"Transfer", &pv.transfer},
 	}
-	pv.lines = []widgetsLine{
-		pv.publicKey,
-		pv.presharedKey,
-		pv.allowedIPs,
-		pv.endpoint,
-		pv.persistentKeepalive,
-		pv.latestHandshake,
-		pv.transfer,
+	var err error
+	if pv.lines, err = createLabelTextLines(items, parent, nil); err != nil {
+		return nil, err
 	}
+
 	layoutInGrid(pv, parent.Layout().(*walk.GridLayout))
-	return pv
+
+	return pv, nil
 }
 
 func layoutInGrid(view widgetsLinesView, layout *walk.GridLayout) {
@@ -381,18 +477,32 @@ func newPaddedGroupGrid(parent walk.Container) (group *walk.GroupBox, err error)
 }
 
 func NewConfView(parent walk.Container) (*ConfView, error) {
+	var err error
+	var disposables walk.Disposables
+	defer disposables.Treat()
+
 	cv := new(ConfView)
-	cv.ScrollView, _ = walk.NewScrollView(parent)
+	if cv.ScrollView, err = walk.NewScrollView(parent); err != nil {
+		return nil, err
+	}
+	disposables.Add(cv)
 	vlayout := walk.NewVBoxLayout()
 	vlayout.SetMargins(walk.Margins{5, 0, 5, 0})
 	cv.SetLayout(vlayout)
-	cv.name, _ = newPaddedGroupGrid(cv)
-	cv.interfaze = newInterfaceView(cv.name)
+	if cv.name, err = newPaddedGroupGrid(cv); err != nil {
+		return nil, err
+	}
+	if cv.interfaze, err = newInterfaceView(cv.name); err != nil {
+		return nil, err
+	}
 	cv.interfaze.toggleActive.button.Clicked().Attach(cv.onToggleActiveClicked)
 	cv.peers = make(map[conf.Key]*peerView)
 	cv.tunnelChangedCB = manager.IPCClientRegisterTunnelChange(cv.onTunnelChanged)
 	cv.SetTunnel(nil)
-	globalState, _ := manager.IPCClientGlobalState()
+	globalState, err := manager.IPCClientGlobalState()
+	if err != nil {
+		return nil, err
+	}
 	cv.interfaze.toggleActive.updateGlobal(globalState)
 
 	if err := walk.InitWrapperWindow(cv); err != nil {
@@ -421,6 +531,9 @@ func NewConfView(parent walk.Container) (*ConfView, error) {
 			}
 		}
 	}()
+
+	disposables.Spare()
+
 	return cv, nil
 }
 
@@ -443,11 +556,11 @@ func (cv *ConfView) onToggleActiveClicked() {
 		if err != nil {
 			cv.Synchronize(func() {
 				if oldState == manager.TunnelUnknown {
-					walk.MsgBox(cv.Form(), "Failed to determine tunnel state", err.Error(), walk.MsgBoxIconError)
+					showErrorCustom(cv.Form(), "Failed to determine tunnel state", err.Error())
 				} else if oldState == manager.TunnelStopped {
-					walk.MsgBox(cv.Form(), "Failed to activate tunnel", err.Error(), walk.MsgBoxIconError)
+					showErrorCustom(cv.Form(), "Failed to activate tunnel", err.Error())
 				} else if oldState == manager.TunnelStarted {
-					walk.MsgBox(cv.Form(), "Failed to deactivate tunnel", err.Error(), walk.MsgBoxIconError)
+					showErrorCustom(cv.Form(), "Failed to deactivate tunnel", err.Error())
 				}
 			})
 		}
@@ -543,9 +656,16 @@ func (cv *ConfView) setTunnel(tunnel *manager.Tunnel, config *conf.Config, state
 			pv.apply(&peer)
 			inverse[pv] = false
 		} else {
-			group, _ := newPaddedGroupGrid(cv)
+			group, err := newPaddedGroupGrid(cv)
+			if err != nil {
+				continue
+			}
 			group.SetTitle("Peer")
-			pv := newPeerView(group)
+			pv, err := newPeerView(group)
+			if err != nil {
+				group.Dispose()
+				continue
+			}
 			pv.apply(&peer)
 			cv.peers[peer.PublicKey] = pv
 		}

ui/editdialog.go

@@ -28,8 +28,25 @@ type EditDialog struct {
 	blockUntunneledTraficCheckGuard bool
 }
 
-func runTunnelEditDialog(owner walk.Form, tunnel *manager.Tunnel) *conf.Config {
-	dlg := &EditDialog{}
+func runEditDialog(owner walk.Form, tunnel *manager.Tunnel) *conf.Config {
+	dlg, err := newEditDialog(owner, tunnel)
+	if showError(err, owner) {
+		return nil
+	}
+
+	if dlg.Run() == walk.DlgCmdOK {
+		return &dlg.config
+	}
+
+	return nil
+}
+
+func newEditDialog(owner walk.Form, tunnel *manager.Tunnel) (*EditDialog, error) {
+	var err error
+	var disposables walk.Disposables
+	defer disposables.Treat()
+
+	dlg := new(EditDialog)
 
 	var title string
 	if tunnel == nil {
@@ -51,7 +68,10 @@ func runTunnelEditDialog(owner walk.Form, tunnel *manager.Tunnel) *conf.Config {
 	layout.SetMargins(walk.Margins{10, 10, 10, 10})
 	layout.SetColumnStretchFactor(1, 3)
 
-	dlg.Dialog, _ = walk.NewDialog(owner)
+	if dlg.Dialog, err = walk.NewDialog(owner); err != nil {
+		return nil, err
+	}
+	disposables.Add(dlg)
 	dlg.SetIcon(owner.Icon())
 	dlg.SetTitle(title)
 	dlg.SetLayout(layout)
@@ -60,34 +80,51 @@ func runTunnelEditDialog(owner walk.Form, tunnel *manager.Tunnel) *conf.Config {
 		dlg.SetIcon(icon)
 	}
 
-	nameLabel, _ := walk.NewTextLabel(dlg)
+	nameLabel, err := walk.NewTextLabel(dlg)
+	if err != nil {
+		return nil, err
+	}
 	layout.SetRange(nameLabel, walk.Rectangle{0, 0, 1, 1})
 	nameLabel.SetTextAlignment(walk.AlignHFarVCenter)
 	nameLabel.SetText("Name:")
 
-	dlg.nameEdit, _ = walk.NewLineEdit(dlg)
+	if dlg.nameEdit, err = walk.NewLineEdit(dlg); err != nil {
+		return nil, err
+	}
 	layout.SetRange(dlg.nameEdit, walk.Rectangle{1, 0, 1, 1})
 	dlg.nameEdit.SetText(dlg.config.Name)
 
-	pubkeyLabel, _ := walk.NewTextLabel(dlg)
+	pubkeyLabel, err := walk.NewTextLabel(dlg)
+	if err != nil {
+		return nil, err
+	}
 	layout.SetRange(pubkeyLabel, walk.Rectangle{0, 1, 1, 1})
 	pubkeyLabel.SetTextAlignment(walk.AlignHFarVCenter)
 	pubkeyLabel.SetText("Public key:")
 
-	dlg.pubkeyEdit, _ = walk.NewLineEdit(dlg)
+	if dlg.pubkeyEdit, err = walk.NewLineEdit(dlg); err != nil {
+		return nil, err
+	}
 	layout.SetRange(dlg.pubkeyEdit, walk.Rectangle{1, 1, 1, 1})
 	dlg.pubkeyEdit.SetReadOnly(true)
 	dlg.pubkeyEdit.SetText("(unknown)")
 
-	dlg.syntaxEdit, _ = syntax.NewSyntaxEdit(dlg)
+	if dlg.syntaxEdit, err = syntax.NewSyntaxEdit(dlg); err != nil {
+		return nil, err
+	}
 	layout.SetRange(dlg.syntaxEdit, walk.Rectangle{0, 2, 2, 1})
 
-	buttonsContainer, _ := walk.NewComposite(dlg)
+	buttonsContainer, err := walk.NewComposite(dlg)
+	if err != nil {
+		return nil, err
+	}
 	layout.SetRange(buttonsContainer, walk.Rectangle{0, 3, 2, 1})
 	buttonsContainer.SetLayout(walk.NewHBoxLayout())
 	buttonsContainer.Layout().SetMargins(walk.Margins{})
 
-	dlg.blockUntunneledTrafficCB, _ = walk.NewCheckBox(buttonsContainer)
+	if dlg.blockUntunneledTrafficCB, err = walk.NewCheckBox(buttonsContainer); err != nil {
+		return nil, err
+	}
 	dlg.blockUntunneledTrafficCB.SetText("Block untunneled traffic (kill-switch)")
 	dlg.blockUntunneledTrafficCB.SetToolTipText("When a configuration has exactly one peer, and that peer has an allowed IPs containing at least one of 0.0.0.0/0 or ::/0, then the tunnel service engages a firewall ruleset to block all traffic that is neither to nor from the tunnel interface, with special exceptions for DHCP and NDP.")
 	dlg.blockUntunneledTrafficCB.SetVisible(false)
@@ -95,11 +132,16 @@ func runTunnelEditDialog(owner walk.Form, tunnel *manager.Tunnel) *conf.Config {
 
 	walk.NewHSpacer(buttonsContainer)
 
-	dlg.saveButton, _ = walk.NewPushButton(buttonsContainer)
+	if dlg.saveButton, err = walk.NewPushButton(buttonsContainer); err != nil {
+		return nil, err
+	}
 	dlg.saveButton.SetText("Save")
 	dlg.saveButton.Clicked().Attach(dlg.onSaveButtonClicked)
 
-	cancelButton, _ := walk.NewPushButton(buttonsContainer)
+	cancelButton, err := walk.NewPushButton(buttonsContainer)
+	if err != nil {
+		return nil, err
+	}
 	cancelButton.SetText("Cancel")
 	cancelButton.Clicked().Attach(dlg.Cancel)
 
@@ -118,11 +160,9 @@ func runTunnelEditDialog(owner walk.Form, tunnel *manager.Tunnel) *conf.Config {
 		})
 	}
 
-	if dlg.Run() == walk.DlgCmdOK {
-		return &dlg.config
-	}
+	disposables.Spare()
 
-	return nil
+	return dlg, nil
 }
 
 func (dlg *EditDialog) onBlockUntunneledTrafficCBCheckedChanged() {
@@ -217,7 +257,7 @@ func (dlg *EditDialog) onBlockUntunneledTrafficCBCheckedChanged() {
 	return
 
 err:
-	walk.MsgBox(dlg, "Invalid configuration", "Unable to toggle untunneled traffic blocking state.", walk.MsgBoxIconWarning)
+	showErrorCustom(dlg, "Invalid configuration", "Unable to toggle untunneled traffic blocking state.")
 	dlg.blockUntunneledTrafficCB.SetVisible(false)
 }
 
@@ -252,11 +292,11 @@ func (dlg *EditDialog) onSyntaxEditPrivateKeyChanged(privateKey string) {
 func (dlg *EditDialog) onSaveButtonClicked() {
 	newName := dlg.nameEdit.Text()
 	if newName == "" {
-		walk.MsgBox(dlg, "Invalid name", "A name is required.", walk.MsgBoxIconWarning)
+		showWarningCustom(dlg, "Invalid name", "A name is required.")
 		return
 	}
 	if !conf.TunnelNameIsValid(newName) {
-		walk.MsgBox(dlg, "Invalid name", fmt.Sprintf("Tunnel name ‘%s’ is invalid.", newName), walk.MsgBoxIconWarning)
+		showWarningCustom(dlg, "Invalid name", fmt.Sprintf("Tunnel name ‘%s’ is invalid.", newName))
 		return
 	}
 	newNameLower := strings.ToLower(newName)
@@ -264,12 +304,12 @@ func (dlg *EditDialog) onSaveButtonClicked() {
 	if newNameLower != strings.ToLower(dlg.config.Name) {
 		existingTunnelList, err := manager.IPCClientTunnels()
 		if err != nil {
-			walk.MsgBox(dlg, "Unable to list existing tunnels", err.Error(), walk.MsgBoxIconError)
+			showWarningCustom(dlg, "Unable to list existing tunnels", err.Error())
 			return
 		}
 		for _, tunnel := range existingTunnelList {
 			if strings.ToLower(tunnel.Name) == newNameLower {
-				walk.MsgBox(dlg, "Tunnel already exists", fmt.Sprintf("Another tunnel already exists with the name ‘%s’.", newName), walk.MsgBoxIconWarning)
+				showWarningCustom(dlg, "Tunnel already exists", fmt.Sprintf("Another tunnel already exists with the name ‘%s’.", newName))
 				return
 			}
 		}
@@ -277,7 +317,7 @@ func (dlg *EditDialog) onSaveButtonClicked() {
 
 	cfg, err := conf.FromWgQuick(dlg.syntaxEdit.Text(), newName)
 	if err != nil {
-		walk.MsgBox(dlg, "Unable to create new configuration", err.Error(), walk.MsgBoxIconError)
+		showErrorCustom(dlg, "Unable to create new configuration", err.Error())
 		return
 	}
 

ui/filesave.go

@@ -18,7 +18,7 @@ func writeFileWithOverwriteHandling(owner walk.Form, filePath string, write func
 			return false
 		}
 
-		walk.MsgBox(owner, "Writing file failed", err.Error(), walk.MsgBoxIconError)
+		showErrorCustom(owner, "Writing file failed", err.Error())
 
 		return true
 	}

ui/logpage.go

@@ -24,11 +24,10 @@ const (
 func NewLogPage() (*LogPage, error) {
 	lp := &LogPage{}
 
+	var err error
 	var disposables walk.Disposables
 	defer disposables.Treat()
 
-	var err error
-
 	if lp.TabPage, err = walk.NewTabPage(); err != nil {
 		return nil, err
 	}
@@ -47,7 +46,11 @@ func NewLogPage() (*LogPage, error) {
 	lp.logView.SetAlternatingRowBGColor(walk.Color(win.GetSysColor(win.COLOR_BTNFACE)))
 	lp.logView.SetLastColumnStretched(true)
 
-	contextMenu, _ := walk.NewMenu()
+	contextMenu, err := walk.NewMenu()
+	if err != nil {
+		return nil, err
+	}
+	lp.logView.AddDisposable(contextMenu)
 	copyAction := walk.NewAction()
 	copyAction.SetText("&Copy")
 	copyAction.SetShortcut(walk.Shortcut{walk.ModControl, walk.KeyC})

ui/managewindow.go

@@ -40,6 +40,8 @@ func init() {
 
 func NewManageTunnelsWindow() (*ManageTunnelsWindow, error) {
 	var err error
+	var disposables walk.Disposables
+	defer disposables.Treat()
 
 	font, err := walk.NewFont("Segoe UI", 9, 0)
 	if err != nil {
@@ -53,6 +55,7 @@ func NewManageTunnelsWindow() (*ManageTunnelsWindow, error) {
 	if err != nil {
 		return nil, err
 	}
+	disposables.Add(mtw)
 	win.ChangeWindowMessageFilterEx(mtw.Handle(), raiseMsg, win.MSGFLT_ALLOW, nil)
 	mtw.SetPersistent(true)
 
@@ -60,7 +63,6 @@ func NewManageTunnelsWindow() (*ManageTunnelsWindow, error) {
 		mtw.SetIcon(icon)
 	}
 	mtw.SetTitle("WireGuard")
-	mtw.AddDisposable(font)
 	mtw.SetFont(font)
 	mtw.SetSize(walk.Size{670, 525})
 	mtw.SetMinMaxSize(walk.Size{500, 400}, walk.Size{0, 0})
@@ -85,7 +87,9 @@ func NewManageTunnelsWindow() (*ManageTunnelsWindow, error) {
 		}
 	})
 
-	mtw.tabs, _ = walk.NewTabWidget(mtw)
+	if mtw.tabs, err = walk.NewTabWidget(mtw); err != nil {
+		return nil, err
+	}
 
 	if mtw.tunnelsPage, err = NewTunnelsPage(); err != nil {
 		return nil, err
@@ -118,6 +122,8 @@ func NewManageTunnelsWindow() (*ManageTunnelsWindow, error) {
 		})
 	}
 
+	disposables.Spare()
+
 	return mtw, nil
 }
 
@@ -157,7 +163,7 @@ func (mtw *ManageTunnelsWindow) onTunnelChange(tunnel *manager.Tunnel, state man
 			if len(errMsg) > 0 && errMsg[len(errMsg)-1] != '.' {
 				errMsg += "."
 			}
-			walk.MsgBox(mtw, "Tunnel Error", errMsg+"\n\nPlease consult the log for more information.", walk.MsgBoxIconWarning)
+			showWarningCustom(mtw, "Tunnel Error", errMsg+"\n\nPlease consult the log for more information.")
 		}
 	})
 }

ui/raise.go

@@ -10,7 +10,6 @@ import (
 	"os"
 	"runtime"
 
-	"github.com/lxn/walk"
 	"github.com/lxn/win"
 	"golang.org/x/sys/windows"
 )
@@ -54,7 +53,7 @@ func WaitForRaiseUIThenQuit() {
 		return 0
 	}, 0, 0, win.WINEVENT_SKIPOWNPROCESS|win.WINEVENT_OUTOFCONTEXT)
 	if err != nil {
-		walk.MsgBox(nil, "WireGuard Detection Error", fmt.Sprintf("Unable to wait for WireGuard window to appear: %v", err), walk.MsgBoxIconError)
+		showErrorCustom(nil, "WireGuard Detection Error", fmt.Sprintf("Unable to wait for WireGuard window to appear: %v", err))
 	}
 	for {
 		var msg win.MSG

ui/tray.go

@@ -160,11 +160,11 @@ func (tray *Tray) addTunnelAction(tunnel *manager.Tunnel) {
 					tray.mtw.tunnelsPage.listView.selectTunnel(tclosure.Name)
 					tray.mtw.tabs.SetCurrentIndex(0)
 					if oldState == manager.TunnelUnknown {
-						walk.MsgBox(tray.mtw, "Failed to determine tunnel state", err.Error(), walk.MsgBoxIconError)
+						showErrorCustom(tray.mtw, "Failed to determine tunnel state", err.Error())
 					} else if oldState == manager.TunnelStopped {
-						walk.MsgBox(tray.mtw, "Failed to activate tunnel", err.Error(), walk.MsgBoxIconError)
+						showErrorCustom(tray.mtw, "Failed to activate tunnel", err.Error())
 					} else if oldState == manager.TunnelStarted {
-						walk.MsgBox(tray.mtw, "Failed to deactivate tunnel", err.Error(), walk.MsgBoxIconError)
+						showErrorCustom(tray.mtw, "Failed to deactivate tunnel", err.Error())
 					}
 				})
 			}

ui/tunnelspage.go

@@ -36,7 +36,6 @@ type TunnelsPage struct {
 
 func NewTunnelsPage() (*TunnelsPage, error) {
 	var err error
-
 	var disposables walk.Disposables
 	defer disposables.Treat()
 
@@ -55,18 +54,20 @@ func NewTunnelsPage() (*TunnelsPage, error) {
 	vlayout.SetSpacing(0)
 	tp.listContainer.SetLayout(vlayout)
 
-	// TODO: deal with remaining disposables in case the next line fails
-
 	if tp.listView, err = NewListView(tp.listContainer); err != nil {
 		return nil, err
 	}
 
-	tp.currentTunnelContainer, _ = walk.NewComposite(tp)
+	if tp.currentTunnelContainer, err = walk.NewComposite(tp); err != nil {
+		return nil, err
+	}
 	vlayout = walk.NewVBoxLayout()
 	vlayout.SetMargins(walk.Margins{})
 	tp.currentTunnelContainer.SetLayout(vlayout)
 
-	tp.fillerContainer, _ = walk.NewComposite(tp)
+	if tp.fillerContainer, err = walk.NewComposite(tp); err != nil {
+		return nil, err
+	}
 	tp.fillerContainer.SetVisible(false)
 	hlayout := walk.NewHBoxLayout()
 	hlayout.SetMargins(walk.Margins{})
@@ -79,15 +80,23 @@ func NewTunnelsPage() (*TunnelsPage, error) {
 		}
 	})
 
-	tp.confView, _ = NewConfView(tp.currentTunnelContainer)
+	if tp.confView, err = NewConfView(tp.currentTunnelContainer); err != nil {
+		return nil, err
+	}
 
-	controlsContainer, _ := walk.NewComposite(tp.currentTunnelContainer)
+	controlsContainer, err := walk.NewComposite(tp.currentTunnelContainer)
+	if err != nil {
+		return nil, err
+	}
 	controlsContainer.SetLayout(walk.NewHBoxLayout())
 	controlsContainer.Layout().SetMargins(walk.Margins{})
 
 	walk.NewHSpacer(controlsContainer)
 
-	editTunnel, _ := walk.NewPushButton(controlsContainer)
+	editTunnel, err := walk.NewPushButton(controlsContainer)
+	if err != nil {
+		return nil, err
+	}
 	editTunnel.SetEnabled(false)
 	tp.listView.CurrentIndexChanged().Attach(func() {
 		editTunnel.SetEnabled(tp.listView.CurrentIndex() > -1)
@@ -107,22 +116,30 @@ func NewTunnelsPage() (*TunnelsPage, error) {
 	return tp, nil
 }
 
-func (tp *TunnelsPage) CreateToolbar() {
+func (tp *TunnelsPage) CreateToolbar() error {
 	if tp.listToolbar != nil {
-		return
+		return nil
 	}
 
 	// HACK: Because of https://github.com/lxn/walk/issues/481
 	// we need to put the ToolBar into its own Composite.
-	toolBarContainer, _ := walk.NewComposite(tp.listContainer)
+	toolBarContainer, err := walk.NewComposite(tp.listContainer)
+	if err != nil {
+		return err
+	}
 	toolBarContainer.SetDoubleBuffering(true)
 	hlayout := walk.NewHBoxLayout()
 	hlayout.SetMargins(walk.Margins{})
 	toolBarContainer.SetLayout(hlayout)
 
-	tp.listToolbar, _ = walk.NewToolBarWithOrientationAndButtonStyle(toolBarContainer, walk.Horizontal, walk.ToolBarButtonImageBeforeText)
+	if tp.listToolbar, err = walk.NewToolBarWithOrientationAndButtonStyle(toolBarContainer, walk.Horizontal, walk.ToolBarButtonImageBeforeText); err != nil {
+		return err
+	}
 
-	addMenu, _ := walk.NewMenu()
+	addMenu, err := walk.NewMenu()
+	if err != nil {
+		return err
+	}
 	tp.AddDisposable(addMenu)
 	importAction := walk.NewAction()
 	importAction.SetText("Import tunnel(s) from file...")
@@ -172,7 +189,11 @@ func (tp *TunnelsPage) CreateToolbar() {
 	fixContainerWidthToToolbarWidth()
 	tp.listToolbar.SizeChanged().Attach(fixContainerWidthToToolbarWidth)
 
-	contextMenu, _ := walk.NewMenu()
+	contextMenu, err := walk.NewMenu()
+	if err != nil {
+		return err
+	}
+	tp.listView.AddDisposable(contextMenu)
 	toggleAction := walk.NewAction()
 	toggleAction.SetText("&Toggle")
 	toggleAction.SetDefault(true)
@@ -238,6 +259,8 @@ func (tp *TunnelsPage) CreateToolbar() {
 	tp.listView.model.RowsRemoved().Attach(setExportRange)
 	tp.listView.model.RowsReset().Attach(setExport)
 	setExport()
+
+	return nil
 }
 
 func (tp *TunnelsPage) updateConfView() {
@@ -383,7 +406,7 @@ func (tp *TunnelsPage) exportTunnels(filePath string) {
 func (tp *TunnelsPage) addTunnel(config *conf.Config) {
 	_, err := manager.IPCClientNewTunnel(config)
 	if err != nil {
-		walk.MsgBox(tp.Form(), "Unable to create tunnel", err.Error(), walk.MsgBoxIconError)
+		showErrorCustom(tp.Form(), "Unable to create tunnel", err.Error())
 	}
 
 }
@@ -400,11 +423,11 @@ func (tp *TunnelsPage) onTunnelsViewItemActivated() {
 		if err != nil {
 			tp.Synchronize(func() {
 				if oldState == manager.TunnelUnknown {
-					walk.MsgBox(tp.Form(), "Failed to determine tunnel state", err.Error(), walk.MsgBoxIconError)
+					showErrorCustom(tp.Form(), "Failed to determine tunnel state", err.Error())
 				} else if oldState == manager.TunnelStopped {
-					walk.MsgBox(tp.Form(), "Failed to activate tunnel", err.Error(), walk.MsgBoxIconError)
+					showErrorCustom(tp.Form(), "Failed to activate tunnel", err.Error())
 				} else if oldState == manager.TunnelStarted {
-					walk.MsgBox(tp.Form(), "Failed to deactivate tunnel", err.Error(), walk.MsgBoxIconError)
+					showErrorCustom(tp.Form(), "Failed to deactivate tunnel", err.Error())
 				}
 			})
 			return
@@ -418,7 +441,7 @@ func (tp *TunnelsPage) onEditTunnel() {
 		return
 	}
 
-	if config := runTunnelEditDialog(tp.Form(), tunnel); config != nil {
+	if config := runEditDialog(tp.Form(), tunnel); config != nil {
 		go func() {
 			priorState, err := tunnel.State()
 			tunnel.Delete()
@@ -432,7 +455,7 @@ func (tp *TunnelsPage) onEditTunnel() {
 }
 
 func (tp *TunnelsPage) onAddTunnel() {
-	if config := runTunnelEditDialog(tp.Form(), nil); config != nil {
+	if config := runEditDialog(tp.Form(), nil); config != nil {
 		// Save new
 		tp.addTunnel(config)
 	}
@@ -493,9 +516,9 @@ func (tp *TunnelsPage) onDelete() {
 		if len(errors) > 0 {
 			tp.listView.Synchronize(func() {
 				if len(errors) == 1 {
-					walk.MsgBox(tp.Form(), "Unable to delete tunnel", fmt.Sprintf("A tunnel was unable to be removed: %s", errors[0].Error()), walk.MsgBoxIconError)
+					showErrorCustom(tp.Form(), "Unable to delete tunnel", fmt.Sprintf("A tunnel was unable to be removed: %s", errors[0].Error()))
 				} else {
-					walk.MsgBox(tp.Form(), "Unable to delete tunnels", fmt.Sprintf("%d tunnels were unable to be removed.", len(errors)), walk.MsgBoxIconError)
+					showErrorCustom(tp.Form(), "Unable to delete tunnels", fmt.Sprintf("%d tunnels were unable to be removed.", len(errors)))
 				}
 			})
 		}

ui/ui.go

@@ -26,7 +26,7 @@ func RunUI() {
 	runtime.LockOSThread()
 	defer func() {
 		if err := recover(); err != nil {
-			walk.MsgBox(nil, "Panic", fmt.Sprint(err, "\n\n", string(debug.Stack())), walk.MsgBoxIconError)
+			showErrorCustom(nil, "Panic", fmt.Sprint(err, "\n\n", string(debug.Stack())))
 			panic(err)
 		}
 	}()
@@ -95,7 +95,7 @@ func RunUI() {
 	if shouldQuitManagerWhenExiting {
 		_, err := manager.IPCClientQuit(true)
 		if err != nil {
-			walk.MsgBox(nil, "Error Exiting WireGuard", fmt.Sprintf("Unable to exit service due to: %v. You may want to stop WireGuard from the service manager.", err), walk.MsgBoxIconError)
+			showErrorCustom(nil, "Error Exiting WireGuard", fmt.Sprintf("Unable to exit service due to: %v. You may want to stop WireGuard from the service manager.", err))
 		}
 	}
 }
@@ -104,3 +104,21 @@ func onQuit() {
 	shouldQuitManagerWhenExiting = true
 	walk.App().Exit(0)
 }
+
+func showError(err error, owner walk.Form) bool {
+	if err == nil {
+		return false
+	}
+
+	showErrorCustom(owner, "Error", err.Error())
+
+	return true
+}
+
+func showErrorCustom(owner walk.Form, title, message string) {
+	walk.MsgBox(owner, title, message, walk.MsgBoxIconError)
+}
+
+func showWarningCustom(owner walk.Form, title, message string) {
+	walk.MsgBox(owner, title, message, walk.MsgBoxIconWarning)
+}

ui/updatepage.go

@@ -19,12 +19,16 @@ type UpdatePage struct {
 }
 
 func NewUpdatePage() (*UpdatePage, error) {
-	up := &UpdatePage{}
 	var err error
+	var disposables walk.Disposables
+	defer disposables.Treat()
+
+	up := &UpdatePage{}
 
 	if up.TabPage, err = walk.NewTabPage(); err != nil {
 		return nil, err
 	}
+	disposables.Add(up)
 
 	up.SetTitle("An Update is Available!")
 
@@ -33,18 +37,30 @@ func NewUpdatePage() (*UpdatePage, error) {
 
 	up.SetLayout(walk.NewVBoxLayout())
 
-	instructions, _ := walk.NewTextLabel(up)
+	instructions, err := walk.NewTextLabel(up)
+	if err != nil {
+		return nil, err
+	}
 	instructions.SetText("An update to WireGuard is available. It is highly advisable to update without delay.")
 	instructions.SetMinMaxSize(walk.Size{1, 0}, walk.Size{0, 0})
 
-	status, _ := walk.NewTextLabel(up)
+	status, err := walk.NewTextLabel(up)
+	if err != nil {
+		return nil, err
+	}
 	status.SetText("Status: Waiting for user")
 	status.SetMinMaxSize(walk.Size{1, 0}, walk.Size{0, 0})
 
-	bar, _ := walk.NewProgressBar(up)
+	bar, err := walk.NewProgressBar(up)
+	if err != nil {
+		return nil, err
+	}
 	bar.SetVisible(false)
 
-	button, _ := walk.NewPushButton(up)
+	button, err := walk.NewPushButton(up)
+	if err != nil {
+		return nil, err
+	}
 	updateIcon, _ := loadSystemIcon("shell32", 46, 32)
 	button.SetImage(updateIcon)
 	button.SetText("Update Now")
@@ -113,5 +129,7 @@ func NewUpdatePage() (*UpdatePage, error) {
 		})
 	})
 
+	disposables.Spare()
+
 	return up, nil
 }