gofiledialog

Explorer-style Open, Save, and Select Folder dialogs for Fyne applications.

gofiledialog is a reusable Go package for apps that need more than Fyne's built-in file dialog exposes. It builds a dialog from Fyne primitives so it can offer switchable views, sortable Details columns, persistent shared settings, file-type filters, New Folder support, and asynchronous image thumbnails.

The public API follows the same shape as Fyne's dialog helpers: use ShowOpen, ShowSave, or ShowFolder for simple cases, or construct a dialog with NewOpen, NewSave, or NewFolder when you want to configure it before showing it.

Features

• Open, Save, and Select Folder dialogs
• Details, List, Small icons, Medium icons, and Large icons views
• Sortable Details columns with persisted column order, visibility, widths, and sort direction
• Shared settings across apps using the OS user config directory
• Places sidebar with Home, Desktop, Documents, Downloads, Pictures, and drives/mounts
• Back, Forward, Up, breadcrumb navigation, editable path entry, and hidden-file toggle
• File-type filters and Save default-extension handling
• New Folder creation and Save overwrite confirmation
• Async image thumbnails with bounded workers, memory cache, and disk cache
• Keyboard polish: Up/Down selection, Enter activation, Backspace up, Escape cancel, and type-ahead search

Install

go get github.com/wierdling/gofiledialog

The package targets Fyne v2 and Go 1.22 or newer.

Quick Start

package main

import (
	"fmt"

	"fyne.io/fyne/v2/app"
	"fyne.io/fyne/v2/widget"

	"github.com/wierdling/gofiledialog"
)

func main() {
	a := app.New()
	win := a.NewWindow("Example")

	btn := widget.NewButton("Open...", func() {
		_ = gofiledialog.ShowOpen(func(paths []string, err error) {
			if err != nil {
				fmt.Println("open failed:", err)
				return
			}
			if len(paths) == 0 {
				fmt.Println("cancelled")
				return
			}
			fmt.Println("chosen:", paths)
		}, win)
	})

	win.SetContent(btn)
	win.ShowAndRun()
}

Open Dialog

err := gofiledialog.ShowOpen(func(paths []string, err error) {
	if err != nil {
		// handle error
		return
	}
	if len(paths) == 0 {
		// cancelled
		return
	}
	// use paths
}, win,
	gofiledialog.WithTitle("Choose images"),
	gofiledialog.WithStartDir(`D:\photos`),
	gofiledialog.WithFilters(
		gofiledialog.Filter{Name: "Images", Extensions: []string{".png", ".jpg", ".jpeg", ".gif", ".bmp", ".tif", ".tiff", ".webp"}},
		gofiledialog.Filter{Name: "All files"},
	),
	gofiledialog.WithMultiSelect(true),
)
if err != nil {
	// dialog construction failed
}

Save Dialog

ShowSave returns the chosen path; it does not create or write the file for you. If the user enters a filename without an extension, the selected filter's first extension is appended.

err := gofiledialog.ShowSave(func(paths []string, err error) {
	if err != nil {
		return
	}
	if len(paths) == 0 {
		return // cancelled
	}

	path := paths[0]
	// write to path
}, win,
	gofiledialog.WithFileName("untitled.txt"),
	gofiledialog.WithFilters(
		gofiledialog.Filter{Name: "Text files", Extensions: []string{".txt"}},
		gofiledialog.Filter{Name: "All files"},
	),
)

Folder Dialog

err := gofiledialog.ShowFolder(func(paths []string, err error) {
	if err != nil {
		return
	}
	if len(paths) == 0 {
		return // cancelled
	}

	folder := paths[0]
	// use folder
}, win)

Configured Dialogs

For more control, construct the dialog, set the callback, then show it:

d, err := gofiledialog.NewOpen(win,
	gofiledialog.WithTitle("Import files"),
	gofiledialog.WithMultiSelect(true),
)
if err != nil {
	return err
}

d.SetOnChosen(func(paths []string, err error) {
	// handle result
})
d.Show()

Options

• WithTitle(title string) sets the dialog window title.
• WithStartDir(dir string) sets the initial directory.
• WithFilters(filters ...Filter) configures the Type dropdown.
• WithMultiSelect(enabled bool) lets Open dialogs accumulate multiple clicked files.
• WithFileName(name string) pre-fills Save dialogs.
• WithStore(store Store) overrides the default shared settings store.

Parent Window Parameter

The parent fyne.Window parameter on ShowOpen, ShowSave, ShowFolder, NewOpen, NewSave, and NewFolder is accepted for API compatibility with Fyne's dialog helpers. gofiledialog currently creates top-level windows and centers them on screen because Fyne's public fyne.Window interface does not expose portable parent-relative window placement.

Settings

By default, view mode, sort column/direction, visible columns, column order, column widths, dialog size, hidden-file visibility, and the last folder are persisted in:

os.UserConfigDir()/wierdling-gofiledialog/settings.json

That means settings are shared by every app on the machine that uses the default gofiledialog store. Use WithStore if an app needs isolated or custom persistence. Settings persistence is best-effort: load failures fall back to defaults, and save failures are ignored so a settings backend cannot break a user's file-dialog interaction.

When no WithStartDir is supplied, the dialog first uses Fyne's saved fyne:fileDialogLastFolder preference (when it names an accessible local folder); otherwise it uses the saved lastDir setting.

The default store writes through a temporary file and atomically replaces the settings file, so readers never observe partial JSON. Saves are serialized within the process and coordinated across processes with a short-lived settings.json.lock file. If another process holds the lock for too long, the save is skipped and the last valid settings file is left intact.

Thumbnails

Icon views show generic file-type icons immediately, then load real image thumbnails asynchronously. Thumbnail work is bounded, prioritized by smaller files first, cached in memory, and cached on disk under the OS user cache directory.

Supported thumbnail formats include PNG, JPEG, GIF, BMP, TIFF, and WebP.

Large files and very high-resolution images are skipped so opening a folder with many photos stays responsive.

Demo

Run the demo:

go run ./cmd/demo

Build the demo:

go build -buildvcs=false -o demo.exe ./cmd/demo

Then run:

.\demo.exe

Development

Run tests:

go test ./...

Check package docs locally:

go doc .

Status

This project is at the first release-pass stage for v0.1.0.

Known limitation: WithMultiSelect(true) currently accumulates clicked files. Native Explorer-style Ctrl/Shift range selection will require custom row/item widgets because Fyne's stock List, Table, and GridWrap callbacks do not expose modifier-key selection state.