Merge pull request #10 from ncruces/dev

List dialog, fix #3.

README.md

@@ -8,15 +8,13 @@ This repo includes both a cross-platform Go package providing
 (simple dialogs that interact graphically with the user),
 as well as a *“port”* of the `zenity` command to both Windows and macOS based on that library.
 
-**This is a work in progress.**
+Implemented dialogs:
-
-Lots of things are missing.
-For now, these are the only implemented dialogs:
 * [message](https://github.com/ncruces/zenity/wiki/Message-dialog) (error, info, question, warning)
+* [text entry](https://github.com/ncruces/zenity/wiki/Text-Entry-dialog)
+* [list](https://github.com/ncruces/zenity/wiki/List-dialog)
+* [password](https://github.com/ncruces/zenity/wiki/Password-dialog)
 * [file selection](https://github.com/ncruces/zenity/wiki/File-Selection-dialog)
 * [color selection](https://github.com/ncruces/zenity/wiki/Color-Selection-dialog)
-* [text entry](https://github.com/ncruces/zenity/wiki/Text-Entry-dialog)
-* [password](https://github.com/ncruces/zenity/wiki/Password-dialog)
 * [notification](https://github.com/ncruces/zenity/wiki/Notification)
 
 Behavior on Windows, macOS and other Unixes might differ slightly.

cmd/zenity/main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"bytes"
 	"context"
+	"errors"
 	"flag"
 	"image/color"
 	"os"
@@ -24,15 +25,16 @@ const (
 
 var (
 	// Application Options
-	notification      bool
-	entryDlg          bool
 	errorDlg          bool
 	infoDlg           bool
 	warningDlg        bool
 	questionDlg       bool
+	entryDlg          bool
+	listDlg           bool
 	passwordDlg       bool
 	fileSelectionDlg  bool
 	colorSelectionDlg bool
+	notification      bool
 
 	// General options
 	title       string
@@ -43,25 +45,29 @@ var (
 	extraButton string
 	text        string
 	icon        string
-
+	multiple    bool
-	// Entry options
-	entryText string
-	hideText  bool
 
 	// Message options
 	noWrap        bool
 	ellipsize     bool
 	defaultCancel bool
 
+	// Entry options
+	entryText string
+	hideText  bool
+
+	// List options
+	columns    int
+	allowEmpty bool
+
 	// File selection options
 	save             bool
-	multiple         bool
 	directory        bool
 	confirmOverwrite bool
 	confirmCreate    bool
 	showHidden       bool
 	filename         string
-	fileFilters      FileFilters
+	fileFilters      zenity.FileFilters
 
 	// Color selection options
 	defaultColor string
@@ -93,12 +99,6 @@ func main() {
 	}
 
 	switch {
-	case notification:
-		errResult(zenity.Notify(text, opts...))
-
-	case entryDlg:
-		strOKResult(zenity.Entry(text, opts...))
-
 	case errorDlg:
 		okResult(zenity.Error(text, opts...))
 	case infoDlg:
@@ -108,6 +108,16 @@ func main() {
 	case questionDlg:
 		okResult(zenity.Question(text, opts...))
 
+	case entryDlg:
+		strOKResult(zenity.Entry(text, opts...))
+
+	case listDlg:
+		if multiple {
+			listResult(zenity.ListMultiple(text, flag.Args(), opts...))
+		} else {
+			strOKResult(zenity.List(text, flag.Args(), opts...))
+		}
+
 	case passwordDlg:
 		_, pw, ok, err := zenity.Password(opts...)
 		strOKResult(pw, ok, err)
@@ -124,6 +134,9 @@ func main() {
 
 	case colorSelectionDlg:
 		colorResult(zenity.SelectColor(opts...))
+
+	case notification:
+		errResult(zenity.Notify(text, opts...))
 	}
 
 	flag.Usage()
@@ -131,15 +144,16 @@ func main() {
 
 func setupFlags() {
 	// Application Options
-	flag.BoolVar(&notification, "notification", false, "Display notification")
-	flag.BoolVar(&entryDlg, "entry", false, "Display text entry dialog")
 	flag.BoolVar(&errorDlg, "error", false, "Display error dialog")
 	flag.BoolVar(&infoDlg, "info", false, "Display info dialog")
 	flag.BoolVar(&warningDlg, "warning", false, "Display warning dialog")
 	flag.BoolVar(&questionDlg, "question", false, "Display question dialog")
+	flag.BoolVar(&entryDlg, "entry", false, "Display text entry dialog")
+	flag.BoolVar(&listDlg, "list", false, "Display list dialog")
 	flag.BoolVar(&passwordDlg, "password", false, "Display password dialog")
 	flag.BoolVar(&fileSelectionDlg, "file-selection", false, "Display file selection dialog")
 	flag.BoolVar(&colorSelectionDlg, "color-selection", false, "Display color selection dialog")
+	flag.BoolVar(&notification, "notification", false, "Display notification")
 
 	// General options
 	flag.StringVar(&title, "title", "", "Set the dialog `title`")
@@ -150,10 +164,7 @@ func setupFlags() {
 	flag.StringVar(&extraButton, "extra-button", "", "Add an extra button")
 	flag.StringVar(&text, "text", "", "Set the dialog `text`")
 	flag.StringVar(&icon, "window-icon", "", "Set the window `icon` (error, info, question, warning)")
-
+	flag.BoolVar(&multiple, "multiple", false, "Allow multiple items to be selected")
-	// Entry options
-	flag.StringVar(&entryText, "entry-text", "", "Set the entry `text`")
-	flag.BoolVar(&hideText, "hide-text", false, "Hide the entry text")
 
 	// Message options
 	flag.StringVar(&icon, "icon-name", "", "Set the dialog `icon` (dialog-error, dialog-information, dialog-question, dialog-warning)")
@@ -161,15 +172,23 @@ func setupFlags() {
 	flag.BoolVar(&ellipsize, "ellipsize", false, "Enable ellipsizing in the dialog text")
 	flag.BoolVar(&defaultCancel, "default-cancel", false, "Give Cancel button focus by default")
 
+	// Entry options
+	flag.StringVar(&entryText, "entry-text", "", "Set the entry `text`")
+	flag.BoolVar(&hideText, "hide-text", false, "Hide the entry text")
+
+	// List options
+	flag.Var(funcValue(addColumn), "column", "Set the column header")
+	flag.Bool("hide-header", true, "Hide the column headers")
+	flag.BoolVar(&allowEmpty, "allow-empty", true, "Allow empty selection (macOS only)")
+
 	// File selection options
 	flag.BoolVar(&save, "save", false, "Activate save mode")
-	flag.BoolVar(&multiple, "multiple", false, "Allow multiple files to be selected")
 	flag.BoolVar(&directory, "directory", false, "Activate directory-only selection")
 	flag.BoolVar(&confirmOverwrite, "confirm-overwrite", false, "Confirm file selection if filename already exists")
 	flag.BoolVar(&confirmCreate, "confirm-create", false, "Confirm file selection if filename does not yet exist (Windows only)")
 	flag.BoolVar(&showHidden, "show-hidden", false, "Show hidden files (Windows and macOS only)")
 	flag.StringVar(&filename, "filename", "", "Set the `filename`")
-	flag.Var(&fileFilters, "file-filter", "Set a filename filter (NAME | PATTERN1 PATTERN2 ...)")
+	flag.Var(funcValue(addFileFilter), "file-filter", "Set a filename filter (NAME | PATTERN1 PATTERN2 ...)")
 
 	// Color selection options
 	flag.StringVar(&defaultColor, "color", "", "Set the `color`")
@@ -196,12 +215,6 @@ func setupFlags() {
 
 func validateFlags() {
 	var n int
-	if notification {
-		n++
-	}
-	if entryDlg {
-		n++
-	}
 	if errorDlg {
 		n++
 	}
@@ -214,6 +227,12 @@ func validateFlags() {
 	if questionDlg {
 		n++
 	}
+	if entryDlg {
+		n++
+	}
+	if listDlg {
+		n++
+	}
 	if passwordDlg {
 		n++
 	}
@@ -223,6 +242,9 @@ func validateFlags() {
 	if colorSelectionDlg {
 		n++
 	}
+	if notification {
+		n++
+	}
 	if n != 1 {
 		flag.Usage()
 	}
@@ -239,11 +261,6 @@ func loadFlags() []zenity.Option {
 		}
 	}
 	switch {
-	case entryDlg:
-		setDefault(&title, "Add a new entry")
-		setDefault(&text, "Enter new text:")
-		setDefault(&okLabel, "OK")
-		setDefault(&cancelLabel, "Cancel")
 	case errorDlg:
 		setDefault(&title, "Error")
 		setDefault(&icon, "dialog-error")
@@ -265,6 +282,16 @@ func loadFlags() []zenity.Option {
 		setDefault(&text, "Are you sure you want to proceed?")
 		setDefault(&okLabel, "Yes")
 		setDefault(&cancelLabel, "No")
+	case entryDlg:
+		setDefault(&title, "Add a new entry")
+		setDefault(&text, "Enter new text:")
+		setDefault(&okLabel, "OK")
+		setDefault(&cancelLabel, "Cancel")
+	case listDlg:
+		setDefault(&title, "Select items from the list")
+		setDefault(&text, "Select items from the list below:")
+		setDefault(&okLabel, "OK")
+		setDefault(&cancelLabel, "Cancel")
 	case passwordDlg:
 		setDefault(&title, "Type your password")
 		setDefault(&icon, "dialog-password")
@@ -308,13 +335,6 @@ func loadFlags() []zenity.Option {
 	}
 	opts = append(opts, zenity.Icon(ico))
 
-	// Entry options
-
-	opts = append(opts, zenity.EntryText(entryText))
-	if hideText {
-		opts = append(opts, zenity.HideText())
-	}
-
 	// Message options
 
 	if noWrap {
@@ -327,6 +347,19 @@ func loadFlags() []zenity.Option {
 		opts = append(opts, zenity.DefaultCancel())
 	}
 
+	// Entry options
+
+	opts = append(opts, zenity.EntryText(entryText))
+	if hideText {
+		opts = append(opts, zenity.HideText())
+	}
+
+	// List options
+
+	if !allowEmpty {
+		opts = append(opts, zenity.DisallowEmpty())
+	}
+
 	// File selection options
 
 	if directory {
@@ -487,18 +520,20 @@ func egestPaths(paths []string, err error) ([]string, error) {
 	return paths, err
 }
 
-// FileFilters is internal.
+type funcValue func(string) error
-type FileFilters struct {
+
-	zenity.FileFilters
+func (f funcValue) String() string     { return "" }
+func (f funcValue) Set(s string) error { return f(s) }
+
+func addColumn(s string) error {
+	columns++
+	if columns <= 1 {
+		return nil
+	}
+	return errors.New("multiple columns not supported")
 }
 
-// String is internal.
+func addFileFilter(s string) error {
-func (f *FileFilters) String() string {
-	return "zenity.FileFilters"
-}
-
-// Set is internal.
-func (f *FileFilters) Set(s string) error {
 	var filter zenity.FileFilter
 
 	if split := strings.SplitN(s, "|", 2); len(split) > 1 {
@@ -507,7 +542,7 @@ func (f *FileFilters) Set(s string) error {
 	}
 
 	filter.Patterns = strings.Split(strings.TrimSpace(s), " ")
-	f.FileFilters = append(f.FileFilters, filter)
+	fileFilters = append(fileFilters, filter)
 
 	return nil
 }

color_darwin.go

@@ -2,7 +2,6 @@ package zenity
 
 import (
 	"image/color"
-	"os/exec"
 
 	"github.com/ncruces/zenity/internal/zenutil"
 )
@@ -21,11 +20,9 @@ func selectColor(opts options) (color.Color, error) {
 		float32(g) / 0xffff,
 		float32(b) / 0xffff,
 	})
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	str, ok, err := strResult(opts, out, err)
-		return nil, nil
+	if ok {
+		return zenutil.ParseColor(str), nil
 	}
-	if err != nil {
 	return nil, err
 }
-	return zenutil.ParseColor(string(out)), nil
-}

color_unix.go

@@ -4,7 +4,6 @@ package zenity
 
 import (
 	"image/color"
-	"os/exec"
 
 	"github.com/ncruces/zenity/internal/zenutil"
 )
@@ -12,9 +11,7 @@ import (
 func selectColor(opts options) (color.Color, error) {
 	args := []string{"--color-selection"}
 
-	if opts.title != nil {
+	args = appendTitle(args, opts)
-		args = append(args, "--title", *opts.title)
-	}
 	if opts.color != nil {
 		args = append(args, "--color", zenutil.UnparseColor(opts.color))
 	}
@@ -23,11 +20,9 @@ func selectColor(opts options) (color.Color, error) {
 	}
 
 	out, err := zenutil.Run(opts.ctx, args)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	str, ok, err := strResult(opts, out, err)
-		return nil, nil
+	if ok {
+		return zenutil.ParseColor(str), nil
 	}
-	if err != nil {
 	return nil, err
 }
-	return zenutil.ParseColor(string(out)), nil
-}

entry.go

@@ -10,15 +10,6 @@ func Entry(text string, options ...Option) (string, bool, error) {
 	return entry(text, applyOptions(options))
 }
 
-// Password displays the password dialog.
-//
-// Returns false on cancel, or ErrExtraButton.
-//
-// Valid options: Title, OKLabel, CancelLabel, ExtraButton, Icon, Username.
-func Password(options ...Option) (usr string, pw string, ok bool, err error) {
-	return password(applyOptions(options))
-}
-
 // EntryText returns an Option to set the entry text.
 func EntryText(text string) Option {
 	return funcOption(func(o *options) { o.entryText = text })
@@ -28,8 +19,3 @@ func EntryText(text string) Option {
 func HideText() Option {
 	return funcOption(func(o *options) { o.hideText = true })
 }
-
-// Username returns an Option to display the username (Unix only).
-func Username() Option {
-	return funcOption(func(o *options) { o.username = true })
-}

entry_darwin.go

@@ -1,9 +1,6 @@
 package zenity
 
 import (
-	"bytes"
-	"os/exec"
-
 	"github.com/ncruces/zenity/internal/zenutil"
 )
 
@@ -19,22 +16,5 @@ func entry(text string, opts options) (string, bool, error) {
 	data.SetButtons(getButtons(true, true, opts))
 
 	out, err := zenutil.Run(opts.ctx, "dialog", data)
-	out = bytes.TrimSuffix(out, []byte{'\n'})
+	return strResult(opts, out, err)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
-		if opts.extraButton != nil &&
-			*opts.extraButton == string(out) {
-			return "", false, ErrExtraButton
-		}
-		return "", false, nil
-	}
-	if err != nil {
-		return "", false, err
-	}
-	return string(out), true, nil
-}
-
-func password(opts options) (string, string, bool, error) {
-	opts.hideText = true
-	pass, ok, err := entry("Password:", opts)
-	return "", pass, ok, err
 }

entry_test.go

@@ -16,11 +16,6 @@ func ExampleEntry() {
 	// Output:
 }
 
-func ExamplePassword() {
-	zenity.Password(zenity.Title("Type your password"))
-	// Output:
-}
-
 func TestEntryTimeout(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Second/10)
 
@@ -41,24 +36,3 @@ func TestEntryCancel(t *testing.T) {
 		t.Error("was not canceled:", err)
 	}
 }
-
-func TestPasswordTimeout(t *testing.T) {
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second/10)
-
-	_, _, _, err := zenity.Password(zenity.Context(ctx))
-	if !os.IsTimeout(err) {
-		t.Error("did not timeout:", err)
-	}
-
-	cancel()
-}
-
-func TestPasswordCancel(t *testing.T) {
-	ctx, cancel := context.WithCancel(context.Background())
-	cancel()
-
-	_, _, _, err := zenity.Password(zenity.Context(ctx))
-	if !errors.Is(err, context.Canceled) {
-		t.Error("was not canceled:", err)
-	}
-}

entry_unix.go

@@ -3,97 +3,22 @@
 package zenity
 
 import (
-	"bytes"
-	"os/exec"
-	"strconv"
-	"strings"
-
 	"github.com/ncruces/zenity/internal/zenutil"
 )
 
 func entry(text string, opts options) (string, bool, error) {
-	args := []string{"--entry", "--text", text, "--entry-text", opts.entryText}
+	args := []string{"--entry", "--text", text}
-	if opts.title != nil {
+	args = appendTitle(args, opts)
-		args = append(args, "--title", *opts.title)
+	args = appendButtons(args, opts)
-	}
+	args = appendWidthHeight(args, opts)
-	if opts.width > 0 {
+	args = appendIcon(args, opts)
-		args = append(args, "--width", strconv.FormatUint(uint64(opts.width), 10))
+	if opts.entryText != "" {
-	}
+		args = append(args, "--entry-text", opts.entryText)
-	if opts.height > 0 {
-		args = append(args, "--height", strconv.FormatUint(uint64(opts.height), 10))
-	}
-	if opts.okLabel != nil {
-		args = append(args, "--ok-label", *opts.okLabel)
-	}
-	if opts.cancelLabel != nil {
-		args = append(args, "--cancel-label", *opts.cancelLabel)
-	}
-	if opts.extraButton != nil {
-		args = append(args, "--extra-button", *opts.extraButton)
 	}
 	if opts.hideText {
 		args = append(args, "--hide-text")
 	}
-	switch opts.icon {
-	case ErrorIcon:
-		args = append(args, "--window-icon=error")
-	case WarningIcon:
-		args = append(args, "--window-icon=warning")
-	case InfoIcon:
-		args = append(args, "--window-icon=info")
-	case QuestionIcon:
-		args = append(args, "--window-icon=question")
-	}
 
 	out, err := zenutil.Run(opts.ctx, args)
-	out = bytes.TrimSuffix(out, []byte{'\n'})
+	return strResult(opts, out, err)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
-		if opts.extraButton != nil &&
-			*opts.extraButton == string(out) {
-			return "", false, ErrExtraButton
-		}
-		return "", false, nil
-	}
-	if err != nil {
-		return "", false, err
-	}
-	return string(out), true, nil
-}
-
-func password(opts options) (string, string, bool, error) {
-	args := []string{"--password"}
-	if opts.title != nil {
-		args = append(args, "--title", *opts.title)
-	}
-	if opts.okLabel != nil {
-		args = append(args, "--ok-label", *opts.okLabel)
-	}
-	if opts.cancelLabel != nil {
-		args = append(args, "--cancel-label", *opts.cancelLabel)
-	}
-	if opts.extraButton != nil {
-		args = append(args, "--extra-button", *opts.extraButton)
-	}
-	if opts.username {
-		args = append(args, "--username")
-	}
-
-	out, err := zenutil.Run(opts.ctx, args)
-	out = bytes.TrimSuffix(out, []byte{'\n'})
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
-		if opts.extraButton != nil &&
-			*opts.extraButton == string(out) {
-			return "", "", false, ErrExtraButton
-		}
-		return "", "", false, nil
-	}
-	if err != nil {
-		return "", "", false, err
-	}
-	if opts.username {
-		if split := strings.SplitN(string(out), "|", 2); len(split) == 2 {
-			return split[0], split[1], true, nil
-		}
-	}
-	return "", string(out), true, nil
 }

entry_windows.go

@@ -1,12 +1,10 @@
 package zenity
 
 import (
-	"strconv"
 	"syscall"
-	"unsafe"
 )
 
-func entry(text string, opts options) (string, bool, error) {
+func entry(text string, opts options) (out string, ok bool, err error) {
 	var title string
 	if opts.title != nil {
 		title = *opts.title
@@ -17,238 +15,17 @@ func entry(text string, opts options) (string, bool, error) {
 	if opts.cancelLabel == nil {
 		opts.cancelLabel = stringPtr("Cancel")
 	}
-	return editBox(title, text, opts)
+	return entryDlg(title, text, opts)
 }
 
-func password(opts options) (string, string, bool, error) {
+func entryDlg(title, text string, opts options) (out string, ok bool, err error) {
-	opts.hideText = true
-	pass, ok, err := entry("Password:", opts)
-	return "", pass, ok, err
-}
-
-var (
-	registerClassEx      = user32.NewProc("RegisterClassExW")
-	unregisterClass      = user32.NewProc("UnregisterClassW")
-	createWindowEx       = user32.NewProc("CreateWindowExW")
-	destroyWindow        = user32.NewProc("DestroyWindow")
-	isDialogMessage      = user32.NewProc("IsDialogMessageW")
-	translateMessage     = user32.NewProc("TranslateMessage")
-	dispatchMessage      = user32.NewProc("DispatchMessageW")
-	postQuitMessage      = user32.NewProc("PostQuitMessage")
-	defWindowProc        = user32.NewProc("DefWindowProcW")
-	getWindowRect        = user32.NewProc("GetWindowRect")
-	setWindowPos         = user32.NewProc("SetWindowPos")
-	setFocus             = user32.NewProc("SetFocus")
-	showWindow           = user32.NewProc("ShowWindow")
-	systemParametersInfo = user32.NewProc("SystemParametersInfoW")
-	getSystemMetrics     = user32.NewProc("GetSystemMetrics")
-	getWindowDC          = user32.NewProc("GetWindowDC")
-	releaseDC            = user32.NewProc("ReleaseDC")
-	getDpiForWindow      = user32.NewProc("GetDpiForWindow")
-
-	deleteObject       = gdi32.NewProc("DeleteObject")
-	getDeviceCaps      = gdi32.NewProc("GetDeviceCaps")
-	createFontIndirect = gdi32.NewProc("CreateFontIndirectW")
-)
-
-// https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-wndclassexw
-type _WNDCLASSEX struct {
-	Size       uint32
-	Style      uint32
-	WndProc    uintptr
-	ClsExtra   int32
-	WndExtra   int32
-	Instance   uintptr
-	Icon       uintptr
-	Cursor     uintptr
-	Background uintptr
-	MenuName   *uint16
-	ClassName  *uint16
-	IconSm     uintptr
-}
-
-// https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-msg
-type _MSG struct {
-	Owner   syscall.Handle
-	Message uint32
-	WParam  uintptr
-	LParam  uintptr
-	Time    uint32
-	Pt      _POINT
-}
-
-// https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-nonclientmetricsw
-type _NONCLIENTMETRICS struct {
-	Size            uint32
-	BorderWidth     int32
-	ScrollWidth     int32
-	ScrollHeight    int32
-	CaptionWidth    int32
-	CaptionHeight   int32
-	CaptionFont     _LOGFONT
-	SmCaptionWidth  int32
-	SmCaptionHeight int32
-	SmCaptionFont   _LOGFONT
-	MenuWidth       int32
-	MenuHeight      int32
-	MenuFont        _LOGFONT
-	StatusFont      _LOGFONT
-	MessageFont     _LOGFONT
-}
-
-// https://docs.microsoft.com/en-us/windows/win32/api/wingdi/ns-wingdi-logfontw
-type _LOGFONT struct {
-	Height         int32
-	Width          int32
-	Escapement     int32
-	Orientation    int32
-	Weight         int32
-	Italic         byte
-	Underline      byte
-	StrikeOut      byte
-	CharSet        byte
-	OutPrecision   byte
-	ClipPrecision  byte
-	Quality        byte
-	PitchAndFamily byte
-	FaceName       [32]uint16
-}
-
-// https://docs.microsoft.com/en-us/windows/win32/api/windef/ns-windef-point
-type _POINT struct {
-	x, y int32
-}
-
-// https://docs.microsoft.com/en-us/windows/win32/api/windef/ns-windef-rect
-type _RECT struct {
-	left   int32
-	top    int32
-	right  int32
-	bottom int32
-}
-
-type dpi uintptr
-
-func getDPI(wnd uintptr) dpi {
-	var res uintptr
-
-	if wnd != 0 && getDpiForWindow.Find() == nil {
-		res, _, _ = getDpiForWindow.Call(wnd)
-	} else if dc, _, _ := getWindowDC.Call(wnd); dc != 0 {
-		res, _, _ = getDeviceCaps.Call(dc, 90) // LOGPIXELSY
-		releaseDC.Call(0, dc)
-	}
-
-	if res == 0 {
-		return 96 // USER_DEFAULT_SCREEN_DPI
-	}
-	return dpi(res)
-}
-
-func (d dpi) Scale(dim uintptr) uintptr {
-	if d == 0 {
-		return dim
-	}
-	return dim * uintptr(d) / 96 // USER_DEFAULT_SCREEN_DPI
-}
-
-type font struct {
-	handle uintptr
-	face   _LOGFONT
-}
-
-func getFont() font {
-	var metrics _NONCLIENTMETRICS
-	metrics.Size = uint32(unsafe.Sizeof(metrics))
-	systemParametersInfo.Call(0x29, // SPI_GETNONCLIENTMETRICS
-		unsafe.Sizeof(metrics), uintptr(unsafe.Pointer(&metrics)), 0)
-	return font{face: metrics.MessageFont}
-}
-
-func (f *font) ForDPI(dpi dpi) uintptr {
-	if h := -int32(dpi.Scale(12)); f.handle == 0 || f.face.Height != h {
-		f.Delete()
-		f.face.Height = h
-		f.handle, _, _ = createFontIndirect.Call(uintptr(unsafe.Pointer(&f.face)))
-	}
-	return f.handle
-}
-
-func (f *font) Delete() {
-	if f.handle != 0 {
-		deleteObject.Call(f.handle)
-		f.handle = 0
-	}
-}
-
-func getWindowTextString(wnd uintptr) string {
-	len, _, _ := getWindowTextLength.Call(wnd)
-	buf := make([]uint16, len+1)
-	getWindowText.Call(wnd, uintptr(unsafe.Pointer(&buf[0])), len+1)
-	return syscall.UTF16ToString(buf)
-}
-
-func centerWindow(wnd uintptr) {
-	getMetric := func(i uintptr) int32 {
-		ret, _, _ := getSystemMetrics.Call(i)
-		return int32(ret)
-	}
-
-	var rect _RECT
-	getWindowRect.Call(wnd, uintptr(unsafe.Pointer(&rect)))
-	x := (getMetric(0 /* SM_CXSCREEN */) - (rect.right - rect.left)) / 2
-	y := (getMetric(1 /* SM_CYSCREEN */) - (rect.bottom - rect.top)) / 2
-	setWindowPos.Call(wnd, 0, uintptr(x), uintptr(y), 0, 0, 0x5) // SWP_NOZORDER|SWP_NOSIZE
-}
-
-func registerClass(instance, proc uintptr) (uintptr, error) {
-	name := "WC_" + strconv.FormatUint(uint64(proc), 16)
-
-	var wcx _WNDCLASSEX
-	wcx.Size = uint32(unsafe.Sizeof(wcx))
-	wcx.WndProc = proc
-	wcx.Instance = instance
-	wcx.Background = 5 // COLOR_WINDOW
-	wcx.ClassName = syscall.StringToUTF16Ptr(name)
-
-	ret, _, err := registerClassEx.Call(uintptr(unsafe.Pointer(&wcx)))
-	return ret, err
-}
-
-// https://docs.microsoft.com/en-us/windows/win32/winmsg/using-messages-and-message-queues
-func messageLoop(wnd uintptr) error {
-	getMessage := getMessage.Addr()
-	isDialogMessage := isDialogMessage.Addr()
-	translateMessage := translateMessage.Addr()
-	dispatchMessage := dispatchMessage.Addr()
-
-	for {
-		var msg _MSG
-		ret, _, err := syscall.Syscall6(getMessage, 4, uintptr(unsafe.Pointer(&msg)), 0, 0, 0, 0, 0)
-		if int32(ret) == -1 {
-			return err
-		}
-		if ret == 0 {
-			return nil
-		}
-
-		ret, _, _ = syscall.Syscall(isDialogMessage, 2, wnd, uintptr(unsafe.Pointer(&msg)), 0)
-		if ret == 0 {
-			syscall.Syscall(translateMessage, 1, uintptr(unsafe.Pointer(&msg)), 0, 0)
-			syscall.Syscall(dispatchMessage, 1, uintptr(unsafe.Pointer(&msg)), 0, 0)
-		}
-	}
-}
-
-func editBox(title, text string, opts options) (out string, ok bool, err error) {
-	var wnd, textCtl, editCtl uintptr
-	var okBtn, cancelBtn, extraBtn uintptr
-	defWindowProc := defWindowProc.Addr()
-
 	defer setup()()
-
 	font := getFont()
 	defer font.Delete()
+	defWindowProc := defWindowProc.Addr()
+
+	var wnd, textCtl, editCtl uintptr
+	var okBtn, cancelBtn, extraBtn uintptr
 
 	layout := func(dpi dpi) {
 		hfont := font.ForDPI(dpi)
@@ -256,17 +33,17 @@ func editBox(title, text string, opts options) (out string, ok bool, err error)
 		sendMessage.Call(editCtl, 0x0030 /* WM_SETFONT */, hfont, 1)
 		sendMessage.Call(okBtn, 0x0030 /* WM_SETFONT */, hfont, 1)
 		sendMessage.Call(cancelBtn, 0x0030 /* WM_SETFONT */, hfont, 1)
-		setWindowPos.Call(wnd, 0, 0, 0, dpi.Scale(281), dpi.Scale(140), 0x6)                            // SWP_NOZORDER|SWP_NOMOVE
+		setWindowPos.Call(wnd, 0, 0, 0, dpi.Scale(281), dpi.Scale(141), 0x6)                            // SWP_NOZORDER|SWP_NOMOVE
 		setWindowPos.Call(textCtl, 0, dpi.Scale(12), dpi.Scale(10), dpi.Scale(241), dpi.Scale(16), 0x4) // SWP_NOZORDER
 		setWindowPos.Call(editCtl, 0, dpi.Scale(12), dpi.Scale(30), dpi.Scale(241), dpi.Scale(24), 0x4) // SWP_NOZORDER
 		if extraBtn == 0 {
-			setWindowPos.Call(okBtn, 0, dpi.Scale(95), dpi.Scale(65), dpi.Scale(75), dpi.Scale(24), 0x4)      // SWP_NOZORDER
+			setWindowPos.Call(okBtn, 0, dpi.Scale(95), dpi.Scale(66), dpi.Scale(75), dpi.Scale(24), 0x4)      // SWP_NOZORDER
-			setWindowPos.Call(cancelBtn, 0, dpi.Scale(178), dpi.Scale(65), dpi.Scale(75), dpi.Scale(24), 0x4) // SWP_NOZORDER
+			setWindowPos.Call(cancelBtn, 0, dpi.Scale(178), dpi.Scale(66), dpi.Scale(75), dpi.Scale(24), 0x4) // SWP_NOZORDER
 		} else {
 			sendMessage.Call(extraBtn, 0x0030 /* WM_SETFONT */, hfont, 1)
-			setWindowPos.Call(okBtn, 0, dpi.Scale(12), dpi.Scale(65), dpi.Scale(75), dpi.Scale(24), 0x4)      // SWP_NOZORDER
+			setWindowPos.Call(okBtn, 0, dpi.Scale(12), dpi.Scale(66), dpi.Scale(75), dpi.Scale(24), 0x4)      // SWP_NOZORDER
-			setWindowPos.Call(extraBtn, 0, dpi.Scale(95), dpi.Scale(65), dpi.Scale(75), dpi.Scale(24), 0x4)   // SWP_NOZORDER
+			setWindowPos.Call(extraBtn, 0, dpi.Scale(95), dpi.Scale(66), dpi.Scale(75), dpi.Scale(24), 0x4)   // SWP_NOZORDER
-			setWindowPos.Call(cancelBtn, 0, dpi.Scale(178), dpi.Scale(65), dpi.Scale(75), dpi.Scale(24), 0x4) // SWP_NOZORDER
+			setWindowPos.Call(cancelBtn, 0, dpi.Scale(178), dpi.Scale(66), dpi.Scale(75), dpi.Scale(24), 0x4) // SWP_NOZORDER
 		}
 	}
 
@@ -283,7 +60,7 @@ func editBox(title, text string, opts options) (out string, ok bool, err error)
 			default:
 				return 1
 			case 1, 6: // IDOK, IDYES
-				out = getWindowTextString(editCtl)
+				out = getWindowString(editCtl)
 				ok = true
 			case 2: // IDCANCEL
 			case 7: // IDNO
@@ -322,7 +99,7 @@ func editBox(title, text string, opts options) (out string, ok bool, err error)
 		0x84c80000, // WS_POPUPWINDOW|WS_CLIPSIBLINGS|WS_DLGFRAME
 		0x80000000, // CW_USEDEFAULT
 		0x80000000, // CW_USEDEFAULT
-		281, 140, 0, 0, instance)
+		281, 141, 0, 0, instance)
 
 	textCtl, _, _ = createWindowEx.Call(0,
 		strptr("STATIC"), strptr(text),
@@ -341,16 +118,16 @@ func editBox(title, text string, opts options) (out string, ok bool, err error)
 	okBtn, _, _ = createWindowEx.Call(0,
 		strptr("BUTTON"), strptr(*opts.okLabel),
 		0x50030001, // WS_CHILD|WS_VISIBLE|WS_GROUP|WS_TABSTOP|BS_DEFPUSHBUTTON
-		12, 65, 75, 24, wnd, 1 /* IDOK */, instance)
+		12, 66, 75, 24, wnd, 1 /* IDOK */, instance)
 	cancelBtn, _, _ = createWindowEx.Call(0,
 		strptr("BUTTON"), strptr(*opts.cancelLabel),
 		0x50010000, // WS_CHILD|WS_VISIBLE|WS_GROUP|WS_TABSTOP
-		12, 65, 75, 24, wnd, 2 /* IDCANCEL */, instance)
+		12, 66, 75, 24, wnd, 2 /* IDCANCEL */, instance)
 	if opts.extraButton != nil {
 		extraBtn, _, _ = createWindowEx.Call(0,
 			strptr("BUTTON"), strptr(*opts.extraButton),
 			0x50010000, // WS_CHILD|WS_VISIBLE|WS_GROUP|WS_TABSTOP
-			12, 65, 75, 24, wnd, 7 /* IDNO */, instance)
+			12, 66, 75, 24, wnd, 7 /* IDNO */, instance)
 	}
 
 	layout(getDPI(wnd))

file_darwin.go

@@ -1,8 +1,6 @@
 package zenity
 
 import (
-	"bytes"
-	"os/exec"
 	"strings"
 
 	"github.com/ncruces/zenity/internal/zenutil"
@@ -22,13 +20,8 @@ func selectFile(opts options) (string, error) {
 	}
 
 	out, err := zenutil.Run(opts.ctx, "file", data)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	str, _, err := strResult(opts, out, err)
-		return "", nil
+	return str, err
-	}
-	if err != nil {
-		return "", err
-	}
-	return string(bytes.TrimSuffix(out, []byte{'\n'})), nil
 }
 
 func selectFileMutiple(opts options) ([]string, error) {
@@ -47,17 +40,7 @@ func selectFileMutiple(opts options) ([]string, error) {
 	}
 
 	out, err := zenutil.Run(opts.ctx, "file", data)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	return lstResult(opts, out, err)
-		return nil, nil
-	}
-	if err != nil {
-		return nil, err
-	}
-	out = bytes.TrimSuffix(out, []byte{'\n'})
-	if len(out) == 0 {
-		return nil, nil
-	}
-	return strings.Split(string(out), zenutil.Separator), nil
 }
 
 func selectFileSave(opts options) (string, error) {
@@ -73,13 +56,8 @@ func selectFileSave(opts options) (string, error) {
 	}
 
 	out, err := zenutil.Run(opts.ctx, "file", data)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	str, _, err := strResult(opts, out, err)
-		return "", nil
+	return str, err
-	}
-	if err != nil {
-		return "", err
-	}
-	return string(bytes.TrimSuffix(out, []byte{'\n'})), nil
 }
 
 func initFilters(filters []FileFilter) []string {

file_unix.go

@@ -3,8 +3,6 @@
 package zenity
 
 import (
-	"bytes"
-	"os/exec"
 	"strings"
 
 	"github.com/ncruces/zenity/internal/zenutil"
@@ -12,78 +10,31 @@ import (
 
 func selectFile(opts options) (string, error) {
 	args := []string{"--file-selection"}
-	if opts.title != nil {
+	args = appendTitle(args, opts)
-		args = append(args, "--title", *opts.title)
+	args = appendFileArgs(args, opts)
-	}
-	if opts.directory {
-		args = append(args, "--directory")
-	}
-	if opts.filename != "" {
-		args = append(args, "--filename", opts.filename)
-	}
-	args = append(args, initFilters(opts.fileFilters)...)
 
 	out, err := zenutil.Run(opts.ctx, args)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	str, _, err := strResult(opts, out, err)
-		return "", nil
+	return str, err
-	}
-	if err != nil {
-		return "", err
-	}
-	return string(bytes.TrimSuffix(out, []byte{'\n'})), nil
 }
 
 func selectFileMutiple(opts options) ([]string, error) {
 	args := []string{"--file-selection", "--multiple", "--separator", zenutil.Separator}
-	if opts.title != nil {
+	args = appendTitle(args, opts)
-		args = append(args, "--title", *opts.title)
+	args = appendFileArgs(args, opts)
-	}
-	if opts.directory {
-		args = append(args, "--directory")
-	}
-	if opts.filename != "" {
-		args = append(args, "--filename", opts.filename)
-	}
-	args = append(args, initFilters(opts.fileFilters)...)
 
 	out, err := zenutil.Run(opts.ctx, args)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	return lstResult(opts, out, err)
-		return nil, nil
-	}
-	if err != nil {
-		return nil, err
-	}
-	out = bytes.TrimSuffix(out, []byte{'\n'})
-	if len(out) == 0 {
-		return nil, nil
-	}
-	return strings.Split(string(out), zenutil.Separator), nil
 }
 
 func selectFileSave(opts options) (string, error) {
 	args := []string{"--file-selection", "--save"}
-	if opts.title != nil {
+	args = appendTitle(args, opts)
-		args = append(args, "--title", *opts.title)
+	args = appendFileArgs(args, opts)
-	}
-	if opts.directory {
-		args = append(args, "--directory")
-	}
-	if opts.confirmOverwrite {
-		args = append(args, "--confirm-overwrite")
-	}
-	if opts.filename != "" {
-		args = append(args, "--filename", opts.filename)
-	}
-	args = append(args, initFilters(opts.fileFilters)...)
 
 	out, err := zenutil.Run(opts.ctx, args)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	str, _, err := strResult(opts, out, err)
-		return "", nil
+	return str, err
-	}
-	if err != nil {
-		return "", err
-	}
-	return string(bytes.TrimSuffix(out, []byte{'\n'})), nil
 }
 
 func initFilters(filters []FileFilter) []string {
@@ -103,3 +54,18 @@ func initFilters(filters []FileFilter) []string {
 	}
 	return res
 }
+
+func appendFileArgs(args []string, opts options) []string {
+	if opts.directory {
+		args = append(args, "--directory")
+	}
+	if opts.filename != "" {
+		args = append(args, "--filename", opts.filename)
+	}
+	if opts.confirmOverwrite {
+		args = append(args, "--confirm-overwrite")
+	}
+	args = append(args, initFilters(opts.fileFilters)...)
+
+	return args
+}

internal/zenutil/color.go

@@ -47,12 +47,9 @@ func ParseColor(s string) color.Color {
 		}
 	}
 
-	c, ok := colornames.Map[strings.ToLower(s)]
+	c, _ := colornames.Map[strings.ToLower(s)]
-	if ok {
 	return c
 }
-	return nil
-}
 
 // UnparseColor is internal.
 func UnparseColor(c color.Color) string {

internal/zenutil/osa_generated.go

@@ -3,8 +3,10 @@
 
 package zenutil
 
-import "encoding/json"
+import (
-import "text/template"
+	"encoding/json"
+	"text/template"
+)
 
 var scripts = template.Must(template.New("").Funcs(template.FuncMap{"json": func(v interface{}) (string, error) {
 	b, err := json.Marshal(v)
@@ -36,6 +38,12 @@ app.activate()
 var res=app.{{.Operation}}({{json .Options}})
 if(Array.isArray(res)){res.join({{json .Separator}})}else{res.toString()}
 {{- end}}
+{{define "list" -}}
+var app=Application.currentApplication()
+app.includeStandardAdditions=true
+var res=app.chooseFromList({{json .Items}},{{json .Options}})
+res.join({{json .Separator}})
+{{- end}}
 {{define "notify" -}}
 var app=Application.currentApplication()
 app.includeStandardAdditions=true

internal/zenutil/osa_generator.go

@@ -100,8 +100,10 @@ var generator = template.Must(template.New("").Parse(`// Code generated by zenit
 
 package zenutil
 
-import "encoding/json"
+import (
-import "text/template"
+	"encoding/json"
+	"text/template"
+)
 
 var scripts = template.Must(template.New("").Funcs(template.FuncMap{"json": func(v interface{}) (string, error) {
 	b, err := json.Marshal(v)

internal/zenutil/osascripts/list.gojs

@@ -0,0 +1,5 @@
+var app = Application.currentApplication()
+app.includeStandardAdditions = true
+
+var res = app.chooseFromList({{json .Items}}, {{json .Options}})
+res.join({{json .Separator}})

internal/zenutil/run_darwin.go

@@ -23,9 +23,9 @@ func Run(ctx context.Context, script string, data interface{}) ([]byte, error) {
 		// Try to use syscall.Exec, fallback to exec.Command.
 		if path, err := exec.LookPath("osascript"); err != nil {
 		} else if t, err := ioutil.TempFile("", ""); err != nil {
+		} else if err := os.Remove(t.Name()); err != nil {
 		} else if _, err := t.WriteString(script); err != nil {
 		} else if _, err := t.Seek(0, 0); err != nil {
-		} else if err := os.Remove(t.Name()); err != nil {
 		} else if err := syscall.Dup2(int(t.Fd()), syscall.Stdin); err != nil {
 		} else if err := os.Stderr.Close(); err != nil {
 		} else {
@@ -86,6 +86,24 @@ type DialogOptions struct {
 	Timeout int      `json:"givingUpAfter,omitempty"`
 }
 
+// List is internal.
+type List struct {
+	Items     []string
+	Separator string
+	Options   ListOptions
+}
+
+// ListOptions is internal.
+type ListOptions struct {
+	Title    *string  `json:"withTitle,omitempty"`
+	Prompt   *string  `json:"withPrompt,omitempty"`
+	OK       *string  `json:"okButtonName,omitempty"`
+	Cancel   *string  `json:"cancelButtonName,omitempty"`
+	Default  []string `json:"defaultItems,omitempty"`
+	Multiple bool     `json:"multipleSelectionsAllowed,omitempty"`
+	Empty    bool     `json:"emptySelectionAllowed,omitempty"`
+}
+
 // Notify is internal.
 type Notify struct {
 	Text    string

list.go

@@ -0,0 +1,45 @@
+package zenity
+
+// List displays the list dialog.
+//
+// Returns false on cancel, or ErrExtraButton.
+//
+// Valid options: Title, Width, Height, OKLabel, CancelLabel, ExtraButton,
+// Icon, DefaultItems, DisallowEmpty.
+func List(text string, items []string, options ...Option) (string, bool, error) {
+	return list(text, items, applyOptions(options))
+}
+
+// ListItems displays the list dialog.
+//
+// Returns false on cancel, or ErrExtraButton.
+func ListItems(text string, items ...string) (string, bool, error) {
+	return List(text, items)
+}
+
+// ListMultiple displays the list dialog, allowing multiple items to be selected.
+//
+// Returns a nil slice on cancel, or ErrExtraButton.
+//
+// Valid options: Title, Width, Height, OKLabel, CancelLabel, ExtraButton,
+// Icon, DefaultItems, DisallowEmpty.
+func ListMultiple(text string, items []string, options ...Option) ([]string, error) {
+	return listMultiple(text, items, applyOptions(options))
+}
+
+// ListMultiple displays the list dialog, allowing multiple items to be selected.
+//
+// Returns a nil slice on cancel, or ErrExtraButton.
+func ListMultipleItems(text string, items ...string) ([]string, error) {
+	return ListMultiple(text, items)
+}
+
+// DefaultItems returns an Option to set the items to initally select (macOS only).
+func DefaultItems(items ...string) Option {
+	return funcOption(func(o *options) { o.defaultItems = items })
+}
+
+// DisallowEmpty returns an Option to not allow zero items to be selected (macOS only).
+func DisallowEmpty() Option {
+	return funcOption(func(o *options) { o.disallowEmpty = true })
+}

list_darwin.go

@@ -0,0 +1,35 @@
+package zenity
+
+import (
+	"github.com/ncruces/zenity/internal/zenutil"
+)
+
+func list(text string, items []string, opts options) (string, bool, error) {
+	var data zenutil.List
+	data.Items = items
+	data.Options.Prompt = &text
+	data.Options.Title = opts.title
+	data.Options.OK = opts.okLabel
+	data.Options.Cancel = opts.cancelLabel
+	data.Options.Default = opts.defaultItems
+	data.Options.Empty = !opts.disallowEmpty
+
+	out, err := zenutil.Run(opts.ctx, "list", data)
+	return strResult(opts, out, err)
+}
+
+func listMultiple(text string, items []string, opts options) ([]string, error) {
+	var data zenutil.List
+	data.Items = items
+	data.Options.Prompt = &text
+	data.Options.Title = opts.title
+	data.Options.OK = opts.okLabel
+	data.Options.Cancel = opts.cancelLabel
+	data.Options.Default = opts.defaultItems
+	data.Options.Empty = !opts.disallowEmpty
+	data.Options.Multiple = true
+	data.Separator = zenutil.Separator
+
+	out, err := zenutil.Run(opts.ctx, "list", data)
+	return lstResult(opts, out, err)
+}

list_test.go

@@ -0,0 +1,66 @@
+package zenity_test
+
+import (
+	"context"
+	"errors"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/ncruces/zenity"
+)
+
+func ExampleList() {
+	zenity.List(
+		"Select items from the list below:",
+		[]string{"apples", "oranges", "bananas", "strawberries"},
+		zenity.Title("Select items from the list"),
+		zenity.DisallowEmpty(),
+	)
+	// Output:
+}
+
+func ExampleListItems() {
+	zenity.ListItems(
+		"Select items from the list below:",
+		"apples", "oranges", "bananas", "strawberries")
+	// Output:
+}
+
+func ExampleListMultiple() {
+	zenity.ListMultiple(
+		"Select items from the list below:",
+		[]string{"apples", "oranges", "bananas", "strawberries"},
+		zenity.Title("Select items from the list"),
+		zenity.DefaultItems("apples", "bananas"),
+	)
+	// Output:
+}
+
+func ExampleListMultipleItems() {
+	zenity.ListMultipleItems(
+		"Select items from the list below:",
+		"apples", "oranges", "bananas", "strawberries")
+	// Output:
+}
+
+func TestListTimeout(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second/10)
+
+	_, _, err := zenity.List("", nil, zenity.Context(ctx))
+	if !os.IsTimeout(err) {
+		t.Error("did not timeout:", err)
+	}
+
+	cancel()
+}
+
+func TestListCancel(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+
+	_, _, err := zenity.List("", nil, zenity.Context(ctx))
+	if !errors.Is(err, context.Canceled) {
+		t.Error("was not canceled:", err)
+	}
+}

list_unix.go

@@ -0,0 +1,31 @@
+// +build !windows,!darwin
+
+package zenity
+
+import (
+	"github.com/ncruces/zenity/internal/zenutil"
+)
+
+func list(text string, items []string, opts options) (string, bool, error) {
+	args := []string{"--list", "--column=", "--hide-header", "--text", text}
+	args = appendTitle(args, opts)
+	args = appendButtons(args, opts)
+	args = appendWidthHeight(args, opts)
+	args = appendIcon(args, opts)
+	args = append(args, items...)
+
+	out, err := zenutil.Run(opts.ctx, args)
+	return strResult(opts, out, err)
+}
+
+func listMultiple(text string, items []string, opts options) ([]string, error) {
+	args := []string{"--list", "--column=", "--hide-header", "--text", text, "--multiple", "--separator", zenutil.Separator}
+	args = appendTitle(args, opts)
+	args = appendButtons(args, opts)
+	args = appendWidthHeight(args, opts)
+	args = appendIcon(args, opts)
+	args = append(args, items...)
+
+	out, err := zenutil.Run(opts.ctx, args)
+	return lstResult(opts, out, err)
+}

list_windows.go

@@ -0,0 +1,199 @@
+package zenity
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+func list(text string, items []string, opts options) (string, bool, error) {
+	var title string
+	if opts.title != nil {
+		title = *opts.title
+	}
+	if opts.okLabel == nil {
+		opts.okLabel = stringPtr("OK")
+	}
+	if opts.cancelLabel == nil {
+		opts.cancelLabel = stringPtr("Cancel")
+	}
+	items, err := listDlg(title, text, items, false, opts)
+	if len(items) == 1 {
+		return items[0], true, err
+	}
+	return "", false, err
+}
+
+func listMultiple(text string, items []string, opts options) ([]string, error) {
+	var title string
+	if opts.title != nil {
+		title = *opts.title
+	}
+	if opts.okLabel == nil {
+		opts.okLabel = stringPtr("OK")
+	}
+	if opts.cancelLabel == nil {
+		opts.cancelLabel = stringPtr("Cancel")
+	}
+	return listDlg(title, text, items, true, opts)
+}
+
+func listDlg(title, text string, items []string, multiple bool, opts options) (out []string, err error) {
+	defer setup()()
+	font := getFont()
+	defer font.Delete()
+	defWindowProc := defWindowProc.Addr()
+
+	var wnd, textCtl, listCtl uintptr
+	var okBtn, cancelBtn, extraBtn uintptr
+
+	layout := func(dpi dpi) {
+		hfont := font.ForDPI(dpi)
+		sendMessage.Call(textCtl, 0x0030 /* WM_SETFONT */, hfont, 1)
+		sendMessage.Call(listCtl, 0x0030 /* WM_SETFONT */, hfont, 1)
+		sendMessage.Call(okBtn, 0x0030 /* WM_SETFONT */, hfont, 1)
+		sendMessage.Call(cancelBtn, 0x0030 /* WM_SETFONT */, hfont, 1)
+		setWindowPos.Call(wnd, 0, 0, 0, dpi.Scale(281), dpi.Scale(281), 0x6)                             // SWP_NOZORDER|SWP_NOMOVE
+		setWindowPos.Call(textCtl, 0, dpi.Scale(12), dpi.Scale(10), dpi.Scale(241), dpi.Scale(16), 0x4)  // SWP_NOZORDER
+		setWindowPos.Call(listCtl, 0, dpi.Scale(12), dpi.Scale(30), dpi.Scale(241), dpi.Scale(164), 0x4) // SWP_NOZORDER
+		if extraBtn == 0 {
+			setWindowPos.Call(okBtn, 0, dpi.Scale(95), dpi.Scale(206), dpi.Scale(75), dpi.Scale(24), 0x4)      // SWP_NOZORDER
+			setWindowPos.Call(cancelBtn, 0, dpi.Scale(178), dpi.Scale(206), dpi.Scale(75), dpi.Scale(24), 0x4) // SWP_NOZORDER
+		} else {
+			sendMessage.Call(extraBtn, 0x0030 /* WM_SETFONT */, hfont, 1)
+			setWindowPos.Call(okBtn, 0, dpi.Scale(12), dpi.Scale(206), dpi.Scale(75), dpi.Scale(24), 0x4)      // SWP_NOZORDER
+			setWindowPos.Call(extraBtn, 0, dpi.Scale(95), dpi.Scale(206), dpi.Scale(75), dpi.Scale(24), 0x4)   // SWP_NOZORDER
+			setWindowPos.Call(cancelBtn, 0, dpi.Scale(178), dpi.Scale(206), dpi.Scale(75), dpi.Scale(24), 0x4) // SWP_NOZORDER
+		}
+	}
+
+	proc := func(wnd uintptr, msg uint32, wparam, lparam uintptr) uintptr {
+		switch msg {
+		case 0x0002: // WM_DESTROY
+			postQuitMessage.Call(0)
+
+		case 0x0010: // WM_CLOSE
+			destroyWindow.Call(wnd)
+
+		case 0x0111: // WM_COMMAND
+			switch wparam {
+			default:
+				return 1
+			case 1, 6: // IDOK, IDYES
+				if multiple {
+					if len, _, _ := sendMessage.Call(listCtl, 0x190 /* LB_GETSELCOUNT */, 0, 0); int32(len) >= 0 {
+						out = make([]string, len)
+						if len > 0 {
+							indices := make([]int32, len)
+							sendMessage.Call(listCtl, 0x191 /* LB_GETSELITEMS */, len, uintptr(unsafe.Pointer(&indices[0])))
+							for i, idx := range indices {
+								out[i] = items[idx]
+							}
+						}
+					}
+				} else {
+					if idx, _, _ := sendMessage.Call(listCtl, 0x188 /* LB_GETCURSEL */, 0, 0); int32(idx) >= 0 {
+						out = []string{items[idx]}
+					} else {
+						out = []string{}
+					}
+				}
+			case 2: // IDCANCEL
+			case 7: // IDNO
+				err = ErrExtraButton
+			}
+			destroyWindow.Call(wnd)
+
+		case 0x02e0: // WM_DPICHANGED
+			layout(dpi(uint32(wparam) >> 16))
+
+		default:
+			ret, _, _ := syscall.Syscall6(defWindowProc, 4, wnd, uintptr(msg), wparam, lparam, 0, 0)
+			return ret
+		}
+
+		return 0
+	}
+
+	if opts.ctx != nil && opts.ctx.Err() != nil {
+		return nil, opts.ctx.Err()
+	}
+
+	instance, _, err := getModuleHandle.Call(0)
+	if instance == 0 {
+		return nil, err
+	}
+
+	cls, err := registerClass(instance, syscall.NewCallback(proc))
+	if cls == 0 {
+		return nil, err
+	}
+	defer unregisterClass.Call(cls, instance)
+
+	wnd, _, _ = createWindowEx.Call(0x10101, // WS_EX_CONTROLPARENT|WS_EX_WINDOWEDGE|WS_EX_DLGMODALFRAME
+		cls, strptr(title),
+		0x84c80000, // WS_POPUPWINDOW|WS_CLIPSIBLINGS|WS_DLGFRAME
+		0x80000000, // CW_USEDEFAULT
+		0x80000000, // CW_USEDEFAULT
+		281, 281, 0, 0, instance)
+
+	textCtl, _, _ = createWindowEx.Call(0,
+		strptr("STATIC"), strptr(text),
+		0x5002e080, // WS_CHILD|WS_VISIBLE|WS_GROUP|SS_WORDELLIPSIS|SS_EDITCONTROL|SS_NOPREFIX
+		12, 10, 241, 16, wnd, 0, instance)
+
+	var flags uintptr = 0x50320000 // WS_CHILD|WS_VISIBLE|WS_VSCROLL|WS_GROUP|WS_TABSTOP
+	if multiple {
+		flags |= 0x0800 // LBS_EXTENDEDSEL
+	}
+	listCtl, _, _ = createWindowEx.Call(0x200, // WS_EX_CLIENTEDGE
+		strptr("LISTBOX"), strptr(opts.entryText),
+		flags,
+		12, 30, 241, 164, wnd, 0, instance)
+
+	okBtn, _, _ = createWindowEx.Call(0,
+		strptr("BUTTON"), strptr(*opts.okLabel),
+		0x50030001, // WS_CHILD|WS_VISIBLE|WS_GROUP|WS_TABSTOP|BS_DEFPUSHBUTTON
+		12, 206, 75, 24, wnd, 1 /* IDOK */, instance)
+	cancelBtn, _, _ = createWindowEx.Call(0,
+		strptr("BUTTON"), strptr(*opts.cancelLabel),
+		0x50010000, // WS_CHILD|WS_VISIBLE|WS_GROUP|WS_TABSTOP
+		12, 206, 75, 24, wnd, 2 /* IDCANCEL */, instance)
+	if opts.extraButton != nil {
+		extraBtn, _, _ = createWindowEx.Call(0,
+			strptr("BUTTON"), strptr(*opts.extraButton),
+			0x50010000, // WS_CHILD|WS_VISIBLE|WS_GROUP|WS_TABSTOP
+			12, 206, 75, 24, wnd, 7 /* IDNO */, instance)
+	}
+
+	for _, item := range items {
+		sendMessage.Call(listCtl, 0x180 /* LB_ADDSTRING */, 0, strptr(item))
+	}
+
+	layout(getDPI(wnd))
+	centerWindow(wnd)
+	setFocus.Call(listCtl)
+	showWindow.Call(wnd, 1 /* SW_SHOWNORMAL */, 0)
+
+	if opts.ctx != nil {
+		wait := make(chan struct{})
+		defer close(wait)
+		go func() {
+			select {
+			case <-opts.ctx.Done():
+				sendMessage.Call(wnd, 0x0112 /* WM_SYSCOMMAND */, 0xf060 /* SC_CLOSE */, 0)
+			case <-wait:
+			}
+		}()
+	}
+
+	// set default values
+	out, err = nil, nil
+
+	if err := messageLoop(wnd); err != nil {
+		return nil, err
+	}
+	if opts.ctx != nil && opts.ctx.Err() != nil {
+		return nil, opts.ctx.Err()
+	}
+	return out, err
+}

msg_darwin.go

@@ -1,9 +1,6 @@
 package zenity
 
 import (
-	"bytes"
-	"os/exec"
-
 	"github.com/ncruces/zenity/internal/zenutil"
 )
 
@@ -36,15 +33,6 @@ func message(kind messageKind, text string, opts options) (bool, error) {
 	data.SetButtons(getButtons(dialog, kind == questionKind, opts))
 
 	out, err := zenutil.Run(opts.ctx, "dialog", data)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	_, ok, err := strResult(opts, out, err)
-		if opts.extraButton != nil &&
+	return ok, err
-			*opts.extraButton == string(bytes.TrimSuffix(out, []byte{'\n'})) {
-			return false, ErrExtraButton
-		}
-		return false, nil
-	}
-	if err != nil {
-		return false, err
-	}
-	return true, err
 }

msg_unix.go

@@ -3,10 +3,6 @@
 package zenity
 
 import (
-	"bytes"
-	"os/exec"
-	"strconv"
-
 	"github.com/ncruces/zenity/internal/zenutil"
 )
 
@@ -22,24 +18,10 @@ func message(kind messageKind, text string, opts options) (bool, error) {
 	case errorKind:
 		args = append(args, "--error")
 	}
-	if opts.title != nil {
+	args = appendTitle(args, opts)
-		args = append(args, "--title", *opts.title)
+	args = appendButtons(args, opts)
-	}
+	args = appendWidthHeight(args, opts)
-	if opts.width > 0 {
+	args = appendIcon(args, opts)
-		args = append(args, "--width", strconv.FormatUint(uint64(opts.width), 10))
-	}
-	if opts.height > 0 {
-		args = append(args, "--height", strconv.FormatUint(uint64(opts.height), 10))
-	}
-	if opts.okLabel != nil {
-		args = append(args, "--ok-label", *opts.okLabel)
-	}
-	if opts.cancelLabel != nil {
-		args = append(args, "--cancel-label", *opts.cancelLabel)
-	}
-	if opts.extraButton != nil {
-		args = append(args, "--extra-button", *opts.extraButton)
-	}
 	if opts.noWrap {
 		args = append(args, "--no-wrap")
 	}
@@ -51,13 +33,13 @@ func message(kind messageKind, text string, opts options) (bool, error) {
 	}
 	switch opts.icon {
 	case ErrorIcon:
-		args = append(args, "--window-icon=error", "--icon-name=dialog-error")
+		args = append(args, "--icon-name=dialog-error")
 	case WarningIcon:
-		args = append(args, "--window-icon=warning", "--icon-name=dialog-warning")
+		args = append(args, "--icon-name=dialog-warning")
 	case InfoIcon:
-		args = append(args, "--window-icon=info", "--icon-name=dialog-information")
+		args = append(args, "--icon-name=dialog-information")
 	case QuestionIcon:
-		args = append(args, "--window-icon=question", "--icon-name=dialog-question")
+		args = append(args, "--icon-name=dialog-question")
 	case PasswordIcon:
 		args = append(args, "--icon-name=dialog-password")
 	case NoIcon:
@@ -65,15 +47,6 @@ func message(kind messageKind, text string, opts options) (bool, error) {
 	}
 
 	out, err := zenutil.Run(opts.ctx, args)
-	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+	_, ok, err := strResult(opts, out, err)
-		if opts.extraButton != nil &&
+	return ok, err
-			*opts.extraButton == string(bytes.TrimSuffix(out, []byte{'\n'})) {
-			return false, ErrExtraButton
-		}
-		return false, nil
-	}
-	if err != nil {
-		return false, err
-	}
-	return true, err
 }

notify_unix.go

@@ -8,9 +8,7 @@ import (
 
 func notify(text string, opts options) error {
 	args := []string{"--notification", "--text", text}
-	if opts.title != nil {
+	args = appendTitle(args, opts)
-		args = append(args, "--title", *opts.title)
-	}
 	switch opts.icon {
 	case ErrorIcon:
 		args = append(args, "--window-icon=dialog-error")

pwd.go

@@ -0,0 +1,15 @@
+package zenity
+
+// Password displays the password dialog.
+//
+// Returns false on cancel, or ErrExtraButton.
+//
+// Valid options: Title, OKLabel, CancelLabel, ExtraButton, Icon, Username.
+func Password(options ...Option) (usr string, pw string, ok bool, err error) {
+	return password(applyOptions(options))
+}
+
+// Username returns an Option to display the username (Unix only).
+func Username() Option {
+	return funcOption(func(o *options) { o.username = true })
+}

pwd_stub.go

@@ -0,0 +1,9 @@
+// +build windows darwin
+
+package zenity
+
+func password(opts options) (string, string, bool, error) {
+	opts.hideText = true
+	str, ok, err := entry("Password:", opts)
+	return "", str, ok, err
+}

pwd_test.go

@@ -0,0 +1,37 @@
+package zenity_test
+
+import (
+	"context"
+	"errors"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/ncruces/zenity"
+)
+
+func ExamplePassword() {
+	zenity.Password(zenity.Title("Type your password"))
+	// Output:
+}
+
+func TestPasswordTimeout(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second/10)
+
+	_, _, _, err := zenity.Password(zenity.Context(ctx))
+	if !os.IsTimeout(err) {
+		t.Error("did not timeout:", err)
+	}
+
+	cancel()
+}
+
+func TestPasswordCancel(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+
+	_, _, _, err := zenity.Password(zenity.Context(ctx))
+	if !errors.Is(err, context.Canceled) {
+		t.Error("was not canceled:", err)
+	}
+}

pwd_unix.go

@@ -0,0 +1,27 @@
+// +build !windows,!darwin
+
+package zenity
+
+import (
+	"strings"
+
+	"github.com/ncruces/zenity/internal/zenutil"
+)
+
+func password(opts options) (string, string, bool, error) {
+	args := []string{"--password"}
+	args = appendTitle(args, opts)
+	args = appendButtons(args, opts)
+	if opts.username {
+		args = append(args, "--username")
+	}
+
+	out, err := zenutil.Run(opts.ctx, args)
+	str, ok, err := strResult(opts, out, err)
+	if ok && opts.username {
+		if split := strings.SplitN(string(out), "|", 2); len(split) == 2 {
+			return split[0], split[1], true, nil
+		}
+	}
+	return "", str, ok, err
+}

util_unix.go

@@ -0,0 +1,78 @@
+// +build !windows
+
+package zenity
+
+import (
+	"bytes"
+	"os/exec"
+	"strconv"
+	"strings"
+
+	"github.com/ncruces/zenity/internal/zenutil"
+)
+
+func appendTitle(args []string, opts options) []string {
+	if opts.title != nil {
+		args = append(args, "--title", *opts.title)
+	}
+	return args
+}
+
+func appendButtons(args []string, opts options) []string {
+	if opts.okLabel != nil {
+		args = append(args, "--ok-label", *opts.okLabel)
+	}
+	if opts.cancelLabel != nil {
+		args = append(args, "--cancel-label", *opts.cancelLabel)
+	}
+	if opts.extraButton != nil {
+		args = append(args, "--extra-button", *opts.extraButton)
+	}
+	return args
+}
+
+func appendWidthHeight(args []string, opts options) []string {
+	if opts.width > 0 {
+		args = append(args, "--width", strconv.FormatUint(uint64(opts.width), 10))
+	}
+	if opts.height > 0 {
+		args = append(args, "--height", strconv.FormatUint(uint64(opts.height), 10))
+	}
+	return args
+}
+
+func appendIcon(args []string, opts options) []string {
+	switch opts.icon {
+	case ErrorIcon:
+		args = append(args, "--window-icon=error")
+	case WarningIcon:
+		args = append(args, "--window-icon=warning")
+	case InfoIcon:
+		args = append(args, "--window-icon=info")
+	case QuestionIcon:
+		args = append(args, "--window-icon=question")
+	}
+	return args
+}
+
+func strResult(opts options, out []byte, err error) (string, bool, error) {
+	out = bytes.TrimSuffix(out, []byte{'\n'})
+	if err, ok := err.(*exec.ExitError); ok && err.ExitCode() == 1 {
+		if opts.extraButton != nil && *opts.extraButton == string(out) {
+			return "", false, ErrExtraButton
+		}
+		return "", false, nil
+	}
+	if err != nil {
+		return "", false, err
+	}
+	return string(out), true, nil
+}
+
+func lstResult(opts options, out []byte, err error) ([]string, error) {
+	str, ok, err := strResult(opts, out, err)
+	if ok {
+		return strings.Split(str, zenutil.Separator), nil
+	}
+	return nil, err
+}

util_windows.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"reflect"
 	"runtime"
+	"strconv"
 	"sync/atomic"
 	"syscall"
 	"unsafe"
@@ -22,6 +23,10 @@ var (
 
 	commDlgExtendedError = comdlg32.NewProc("CommDlgExtendedError")
 
+	deleteObject       = gdi32.NewProc("DeleteObject")
+	getDeviceCaps      = gdi32.NewProc("GetDeviceCaps")
+	createFontIndirect = gdi32.NewProc("CreateFontIndirectW")
+
 	getModuleHandle    = kernel32.NewProc("GetModuleHandleW")
 	getCurrentThreadId = kernel32.NewProc("GetCurrentThreadId")
 	getConsoleWindow   = kernel32.NewProc("GetConsoleWindow")
@@ -33,9 +38,13 @@ var (
 
 	getMessage                   = user32.NewProc("GetMessageW")
 	sendMessage                  = user32.NewProc("SendMessageW")
+	postQuitMessage              = user32.NewProc("PostQuitMessage")
+	isDialogMessage              = user32.NewProc("IsDialogMessageW")
+	dispatchMessage              = user32.NewProc("DispatchMessageW")
+	translateMessage             = user32.NewProc("TranslateMessage")
 	getClassName                 = user32.NewProc("GetClassNameW")
-	setWindowsHookEx             = user32.NewProc("SetWindowsHookExW")
 	unhookWindowsHookEx          = user32.NewProc("UnhookWindowsHookEx")
+	setWindowsHookEx             = user32.NewProc("SetWindowsHookExW")
 	callNextHookEx               = user32.NewProc("CallNextHookEx")
 	enumWindows                  = user32.NewProc("EnumWindows")
 	enumChildWindows             = user32.NewProc("EnumChildWindows")
@@ -45,8 +54,30 @@ var (
 	setForegroundWindow          = user32.NewProc("SetForegroundWindow")
 	getWindowThreadProcessId     = user32.NewProc("GetWindowThreadProcessId")
 	setThreadDpiAwarenessContext = user32.NewProc("SetThreadDpiAwarenessContext")
+	getDpiForWindow              = user32.NewProc("GetDpiForWindow")
+	releaseDC                    = user32.NewProc("ReleaseDC")
+	getWindowDC                  = user32.NewProc("GetWindowDC")
+	systemParametersInfo         = user32.NewProc("SystemParametersInfoW")
+	setWindowPos                 = user32.NewProc("SetWindowPos")
+	getWindowRect                = user32.NewProc("GetWindowRect")
+	getSystemMetrics             = user32.NewProc("GetSystemMetrics")
+	unregisterClass              = user32.NewProc("UnregisterClassW")
+	registerClassEx              = user32.NewProc("RegisterClassExW")
+	destroyWindow                = user32.NewProc("DestroyWindow")
+	createWindowEx               = user32.NewProc("CreateWindowExW")
+	showWindow                   = user32.NewProc("ShowWindow")
+	setFocus                     = user32.NewProc("SetFocus")
+	defWindowProc                = user32.NewProc("DefWindowProcW")
 )
 
+func intptr(i int64) uintptr {
+	return uintptr(i)
+}
+
+func strptr(s string) uintptr {
+	return uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(s)))
+}
+
 func setup() context.CancelFunc {
 	var hwnd uintptr
 	enumWindows.Call(syscall.NewCallback(func(wnd, lparam uintptr) uintptr {
@@ -83,8 +114,8 @@ func setup() context.CancelFunc {
 	return func() {
 		if old != 0 {
 			setThreadDpiAwarenessContext.Call(old)
-			runtime.UnlockOSThread()
 		}
+		runtime.UnlockOSThread()
 	}
 }
 
@@ -97,15 +128,6 @@ func commDlgError() error {
 	}
 }
 
-// https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-cwpretstruct
-type _CWPRETSTRUCT struct {
-	Result  uintptr
-	LParam  uintptr
-	WParam  uintptr
-	Message uint32
-	Wnd     uintptr
-}
-
 func hookDialog(ctx context.Context, initDialog func(wnd uintptr)) (unhook context.CancelFunc, err error) {
 	if ctx != nil && ctx.Err() != nil {
 		return nil, ctx.Err()
@@ -174,12 +196,202 @@ func hookDialogTitle(ctx context.Context, title *string) (unhook context.CancelF
 	return hookDialog(ctx, init)
 }
 
-func strptr(s string) uintptr {
+type dpi uintptr
-	return uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(s)))
+
+func getDPI(wnd uintptr) dpi {
+	var res uintptr
+
+	if wnd != 0 && getDpiForWindow.Find() == nil {
+		res, _, _ = getDpiForWindow.Call(wnd)
+	} else if dc, _, _ := getWindowDC.Call(wnd); dc != 0 {
+		res, _, _ = getDeviceCaps.Call(dc, 90) // LOGPIXELSY
+		releaseDC.Call(0, dc)
 	}
 
-func intptr(i int64) uintptr {
+	if res == 0 {
-	return uintptr(i)
+		return 96 // USER_DEFAULT_SCREEN_DPI
+	}
+	return dpi(res)
+}
+
+func (d dpi) Scale(dim uintptr) uintptr {
+	if d == 0 {
+		return dim
+	}
+	return dim * uintptr(d) / 96 // USER_DEFAULT_SCREEN_DPI
+}
+
+type font struct {
+	handle  uintptr
+	logical _LOGFONT
+}
+
+func getFont() font {
+	var metrics _NONCLIENTMETRICS
+	metrics.Size = uint32(unsafe.Sizeof(metrics))
+	systemParametersInfo.Call(0x29, // SPI_GETNONCLIENTMETRICS
+		unsafe.Sizeof(metrics), uintptr(unsafe.Pointer(&metrics)), 0)
+	return font{logical: metrics.MessageFont}
+}
+
+func (f *font) ForDPI(dpi dpi) uintptr {
+	if h := -int32(dpi.Scale(12)); f.handle == 0 || f.logical.Height != h {
+		f.Delete()
+		f.logical.Height = h
+		f.handle, _, _ = createFontIndirect.Call(uintptr(unsafe.Pointer(&f.logical)))
+	}
+	return f.handle
+}
+
+func (f *font) Delete() {
+	if f.handle != 0 {
+		deleteObject.Call(f.handle)
+		f.handle = 0
+	}
+}
+
+func centerWindow(wnd uintptr) {
+	getMetric := func(i uintptr) int32 {
+		ret, _, _ := getSystemMetrics.Call(i)
+		return int32(ret)
+	}
+
+	var rect _RECT
+	getWindowRect.Call(wnd, uintptr(unsafe.Pointer(&rect)))
+	x := (getMetric(0 /* SM_CXSCREEN */) - (rect.right - rect.left)) / 2
+	y := (getMetric(1 /* SM_CYSCREEN */) - (rect.bottom - rect.top)) / 2
+	setWindowPos.Call(wnd, 0, uintptr(x), uintptr(y), 0, 0, 0x5) // SWP_NOZORDER|SWP_NOSIZE
+}
+
+func getWindowString(wnd uintptr) string {
+	len, _, _ := getWindowTextLength.Call(wnd)
+	buf := make([]uint16, len+1)
+	getWindowText.Call(wnd, uintptr(unsafe.Pointer(&buf[0])), len+1)
+	return syscall.UTF16ToString(buf)
+}
+
+func registerClass(instance, proc uintptr) (uintptr, error) {
+	name := "WC_" + strconv.FormatUint(uint64(proc), 16)
+
+	var wcx _WNDCLASSEX
+	wcx.Size = uint32(unsafe.Sizeof(wcx))
+	wcx.WndProc = proc
+	wcx.Instance = instance
+	wcx.Background = 5 // COLOR_WINDOW
+	wcx.ClassName = syscall.StringToUTF16Ptr(name)
+
+	ret, _, err := registerClassEx.Call(uintptr(unsafe.Pointer(&wcx)))
+	return ret, err
+}
+
+// https://docs.microsoft.com/en-us/windows/win32/winmsg/using-messages-and-message-queues
+func messageLoop(wnd uintptr) error {
+	getMessage := getMessage.Addr()
+	isDialogMessage := isDialogMessage.Addr()
+	translateMessage := translateMessage.Addr()
+	dispatchMessage := dispatchMessage.Addr()
+
+	for {
+		var msg _MSG
+		ret, _, err := syscall.Syscall6(getMessage, 4, uintptr(unsafe.Pointer(&msg)), 0, 0, 0, 0, 0)
+		if int32(ret) == -1 {
+			return err
+		}
+		if ret == 0 {
+			return nil
+		}
+
+		ret, _, _ = syscall.Syscall(isDialogMessage, 2, wnd, uintptr(unsafe.Pointer(&msg)), 0)
+		if ret == 0 {
+			syscall.Syscall(translateMessage, 1, uintptr(unsafe.Pointer(&msg)), 0, 0)
+			syscall.Syscall(dispatchMessage, 1, uintptr(unsafe.Pointer(&msg)), 0, 0)
+		}
+	}
+}
+
+// https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-cwpretstruct
+type _CWPRETSTRUCT struct {
+	Result  uintptr
+	LParam  uintptr
+	WParam  uintptr
+	Message uint32
+	Wnd     uintptr
+}
+
+// https://docs.microsoft.com/en-us/windows/win32/api/wingdi/ns-wingdi-logfontw
+type _LOGFONT struct {
+	Height         int32
+	Width          int32
+	Escapement     int32
+	Orientation    int32
+	Weight         int32
+	Italic         byte
+	Underline      byte
+	StrikeOut      byte
+	CharSet        byte
+	OutPrecision   byte
+	ClipPrecision  byte
+	Quality        byte
+	PitchAndFamily byte
+	FaceName       [32]uint16
+}
+
+// https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-nonclientmetricsw
+type _NONCLIENTMETRICS struct {
+	Size            uint32
+	BorderWidth     int32
+	ScrollWidth     int32
+	ScrollHeight    int32
+	CaptionWidth    int32
+	CaptionHeight   int32
+	CaptionFont     _LOGFONT
+	SmCaptionWidth  int32
+	SmCaptionHeight int32
+	SmCaptionFont   _LOGFONT
+	MenuWidth       int32
+	MenuHeight      int32
+	MenuFont        _LOGFONT
+	StatusFont      _LOGFONT
+	MessageFont     _LOGFONT
+}
+
+// https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-msg
+type _MSG struct {
+	Owner   syscall.Handle
+	Message uint32
+	WParam  uintptr
+	LParam  uintptr
+	Time    uint32
+	Pt      _POINT
+}
+
+// https://docs.microsoft.com/en-us/windows/win32/api/windef/ns-windef-point
+type _POINT struct {
+	x, y int32
+}
+
+// https://docs.microsoft.com/en-us/windows/win32/api/windef/ns-windef-rect
+type _RECT struct {
+	left   int32
+	top    int32
+	right  int32
+	bottom int32
+}
+
+// https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-wndclassexw
+type _WNDCLASSEX struct {
+	Size       uint32
+	Style      uint32
+	WndProc    uintptr
+	ClsExtra   int32
+	WndExtra   int32
+	Instance   uintptr
+	Icon       uintptr
+	Cursor     uintptr
+	Background uintptr
+	MenuName   *uint16
+	ClassName  *uint16
+	IconSm     uintptr
 }
 
 // https://github.com/wine-mirror/wine/blob/master/include/unknwn.idl

util_windows_test.go

@@ -1,5 +0,0 @@
-package zenity
-
-func init() {
-	user32.NewProc("SetProcessDPIAware").Call()
-}

zenity.go

@@ -41,6 +41,10 @@ type options struct {
 	ellipsize     bool
 	defaultCancel bool
 
+	// List options
+	disallowEmpty bool
+	defaultItems  []string
+
 	// File selection options
 	directory        bool
 	confirmOverwrite bool