gui/docs/ref/wails-v3/features/dialogs/file.mdx
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refactor: update import path from go-config to core/config
Co-Authored-By: Virgil <virgil@lethean.io>
2026-03-14 10:26:36 +00:00

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---
title: File dialogs
description: Open, save, and folder selection dialogs
sidebar:
order: 3
---
import { Card, CardGrid } from "@astrojs/starlight/components";
## File dialogs
Wails provides **native file dialogs** with platform-appropriate appearance for opening files, saving files, and selecting folders. Simple API with file type filtering, multiple selection support, and default locations.
## Creating File Dialogs
File dialogs are accessed through the `app.Dialog` manager:
```go
app.Dialog.OpenFile()
app.Dialog.SaveFile()
```
## Open File dialog
Select files to open:
```go
path, err := app.Dialog.OpenFile().
SetTitle("Select Image").
AddFilter("Images", "*.png;*.jpg;*.gif").
AddFilter("All Files", "*.*").
PromptForSingleSelection()
if err != nil || path == "" {
return
}
openFile(path)
```
**Use cases:**
- Open documents
- Import files
- Load images
- Select configuration files
### Single File Selection
```go
path, err := app.Dialog.OpenFile().
SetTitle("Open Document").
AddFilter("Text Files", "*.txt").
AddFilter("All Files", "*.*").
PromptForSingleSelection()
if err != nil || path == "" {
// User cancelled or error occurred
return
}
// Use selected file
data, _ := os.ReadFile(path)
```
### Multiple File Selection
```go
paths, err := app.Dialog.OpenFile().
SetTitle("Select Images").
AddFilter("Images", "*.png;*.jpg;*.jpeg;*.gif").
PromptForMultipleSelection()
if err != nil {
return
}
// Process all selected files
for _, path := range paths {
processFile(path)
}
```
### With Default Directory
```go
path, err := app.Dialog.OpenFile().
SetTitle("Open File").
SetDirectory("/Users/me/Documents").
PromptForSingleSelection()
```
## Save File dialog
Choose where to save:
```go
path, err := app.Dialog.SaveFile().
SetFilename("document.txt").
AddFilter("Text Files", "*.txt").
AddFilter("All Files", "*.*").
PromptForSingleSelection()
if err != nil || path == "" {
return
}
saveFile(path, data)
```
**Use cases:**
- Save documents
- Export data
- Create new files
- Save as...
### With Default Filename
```go
path, err := app.Dialog.SaveFile().
SetFilename("export.csv").
AddFilter("CSV Files", "*.csv").
PromptForSingleSelection()
```
### With Default Directory
```go
path, err := app.Dialog.SaveFile().
SetDirectory("/Users/me/Documents").
SetFilename("untitled.txt").
PromptForSingleSelection()
```
### Overwrite Confirmation
```go
path, err := app.Dialog.SaveFile().
SetFilename("document.txt").
PromptForSingleSelection()
if err != nil || path == "" {
return
}
// Check if file exists
if _, err := os.Stat(path); err == nil {
dialog := app.Dialog.Question().
SetTitle("Confirm Overwrite").
SetMessage("File already exists. Overwrite?")
overwriteBtn := dialog.AddButton("Overwrite")
overwriteBtn.OnClick(func() {
saveFile(path, data)
})
cancelBtn := dialog.AddButton("Cancel")
dialog.SetDefaultButton(cancelBtn)
dialog.SetCancelButton(cancelBtn)
dialog.Show()
return
}
saveFile(path, data)
```
## Select Folder dialog
Choose a directory using the open file dialog with directory selection enabled:
```go
path, err := app.Dialog.OpenFile().
SetTitle("Select Output Folder").
CanChooseDirectories(true).
CanChooseFiles(false).
PromptForSingleSelection()
if err != nil || path == "" {
return
}
exportToFolder(path)
```
**Use cases:**
- Choose output directory
- Select workspace
- Pick backup location
- Choose installation directory
### With Default Directory
```go
path, err := app.Dialog.OpenFile().
SetTitle("Select Folder").
SetDirectory("/Users/me/Documents").
CanChooseDirectories(true).
CanChooseFiles(false).
PromptForSingleSelection()
```
## File Filters
Use the `AddFilter()` method to add file type filters to dialogs. Each call adds a new filter option.
### Basic Filters
```go
path, _ := app.Dialog.OpenFile().
AddFilter("Text Files", "*.txt").
AddFilter("All Files", "*.*").
PromptForSingleSelection()
```
### Multiple Extensions
Use semicolons to specify multiple extensions in a single filter:
```go
dialog := app.Dialog.OpenFile().
AddFilter("Images", "*.png;*.jpg;*.jpeg;*.gif;*.bmp").
AddFilter("Documents", "*.txt;*.doc;*.docx;*.pdf").
AddFilter("All Files", "*.*")
```
### Pattern Format
Use **semicolons** to separate multiple extensions in a single filter:
```go
// Multiple extensions separated by semicolons
AddFilter("Images", "*.png;*.jpg;*.gif")
```
## Complete Examples
### Open Image File
```go
func openImage(app *application.App) (image.Image, error) {
path, err := app.Dialog.OpenFile().
SetTitle("Select Image").
AddFilter("Images", "*.png;*.jpg;*.jpeg;*.gif;*.bmp").
PromptForSingleSelection()
if err != nil {
return nil, err
}
if path == "" {
return nil, errors.New("no file selected")
}
// Open and decode image
file, err := os.Open(path)
if err != nil {
app.Dialog.Error().
SetTitle("Open Failed").
SetMessage(err.Error()).
Show()
return nil, err
}
defer file.Close()
img, _, err := image.Decode(file)
if err != nil {
app.Dialog.Error().
SetTitle("Invalid Image").
SetMessage("Could not decode image file.").
Show()
return nil, err
}
return img, nil
}
```
### Save Document with Validation
```go
func saveDocument(app *application.App, content string) {
path, err := app.Dialog.SaveFile().
SetFilename("document.txt").
AddFilter("Text Files", "*.txt").
AddFilter("Markdown Files", "*.md").
AddFilter("All Files", "*.*").
PromptForSingleSelection()
if err != nil || path == "" {
return
}
// Validate extension
ext := filepath.Ext(path)
if ext != ".txt" && ext != ".md" {
dialog := app.Dialog.Question().
SetTitle("Confirm Extension").
SetMessage(fmt.Sprintf("Save as %s file?", ext))
saveBtn := dialog.AddButton("Save")
saveBtn.OnClick(func() {
doSave(app, path, content)
})
cancelBtn := dialog.AddButton("Cancel")
dialog.SetDefaultButton(cancelBtn)
dialog.SetCancelButton(cancelBtn)
dialog.Show()
return
}
doSave(app, path, content)
}
func doSave(app *application.App, path, content string) {
if err := os.WriteFile(path, []byte(content), 0644); err != nil {
app.Dialog.Error().
SetTitle("Save Failed").
SetMessage(err.Error()).
Show()
return
}
app.Dialog.Info().
SetTitle("Saved").
SetMessage("Document saved successfully!").
Show()
}
```
### Batch File Processing
```go
func processMultipleFiles(app *application.App) {
paths, err := app.Dialog.OpenFile().
SetTitle("Select Files to Process").
AddFilter("Images", "*.png;*.jpg").
PromptForMultipleSelection()
if err != nil || len(paths) == 0 {
return
}
// Confirm processing
dialog := app.Dialog.Question().
SetTitle("Confirm Processing").
SetMessage(fmt.Sprintf("Process %d file(s)?", len(paths)))
processBtn := dialog.AddButton("Process")
processBtn.OnClick(func() {
// Process files
var errs []error
for i, path := range paths {
if err := processFile(path); err != nil {
errs = append(errs, err)
}
// Update progress
// app.Event.Emit("progress", map[string]interface{}{
// "current": i + 1,
// "total": len(paths),
// })
_ = i // suppress unused variable warning in example
}
// Show results
if len(errs) > 0 {
app.Dialog.Warning().
SetTitle("Processing Complete").
SetMessage(fmt.Sprintf("Processed %d files with %d errors.",
len(paths), len(errs))).
Show()
} else {
app.Dialog.Info().
SetTitle("Success").
SetMessage(fmt.Sprintf("Processed %d files successfully!", len(paths))).
Show()
}
})
cancelBtn := dialog.AddButton("Cancel")
dialog.SetCancelButton(cancelBtn)
dialog.Show()
}
```
### Export with Folder Selection
```go
func exportData(app *application.App, data []byte) {
// Select output folder
folder, err := app.Dialog.OpenFile().
SetTitle("Select Export Folder").
SetDirectory(getDefaultExportFolder()).
CanChooseDirectories(true).
CanChooseFiles(false).
PromptForSingleSelection()
if err != nil || folder == "" {
return
}
// Generate filename
filename := fmt.Sprintf("export_%s.csv",
time.Now().Format("2006-01-02_15-04-05"))
path := filepath.Join(folder, filename)
// Save file
if err := os.WriteFile(path, data, 0644); err != nil {
app.Dialog.Error().
SetTitle("Export Failed").
SetMessage(err.Error()).
Show()
return
}
// Show success with option to open folder
dialog := app.Dialog.Question().
SetTitle("Export Complete").
SetMessage(fmt.Sprintf("Exported to %s", filename))
openBtn := dialog.AddButton("Open Folder")
openBtn.OnClick(func() {
openFolder(folder)
})
dialog.AddButton("OK")
dialog.Show()
}
```
### Import with Validation
```go
func importConfiguration(app *application.App) {
path, err := app.Dialog.OpenFile().
SetTitle("Import Configuration").
AddFilter("JSON Files", "*.json").
AddFilter("YAML Files", "*.yaml;*.yml").
PromptForSingleSelection()
if err != nil || path == "" {
return
}
// Read file
data, err := os.ReadFile(path)
if err != nil {
app.Dialog.Error().
SetTitle("Read Failed").
SetMessage(err.Error()).
Show()
return
}
// Validate configuration
config, err := parseConfig(data)
if err != nil {
app.Dialog.Error().
SetTitle("Invalid Configuration").
SetMessage("File is not a valid configuration.").
Show()
return
}
// Confirm import
dialog := app.Dialog.Question().
SetTitle("Confirm Import").
SetMessage("Import this configuration?")
importBtn := dialog.AddButton("Import")
importBtn.OnClick(func() {
// Apply configuration
if err := applyConfig(config); err != nil {
app.Dialog.Error().
SetTitle("Import Failed").
SetMessage(err.Error()).
Show()
return
}
app.Dialog.Info().
SetTitle("Success").
SetMessage("Configuration imported successfully!").
Show()
})
cancelBtn := dialog.AddButton("Cancel")
dialog.SetCancelButton(cancelBtn)
dialog.Show()
}
```
## Best Practices
### ✅ Do
- **Provide file filters** - Help users find files
- **Set appropriate titles** - Clear context
- **Use default directories** - Start in logical location
- **Validate selections** - Check file types
- **Handle cancellation** - User might cancel
- **Show confirmation** - For destructive actions
- **Provide feedback** - Success/error messages
### ❌ Don't
- **Don't skip validation** - Check file types
- **Don't ignore errors** - Handle cancellation
- **Don't use generic filters** - Be specific
- **Don't forget "All Files"** - Always include as option
- **Don't hardcode paths** - Use user's home directory
- **Don't assume file exists** - Check before opening
## Platform Differences
### macOS
- Native NSOpenPanel/NSSavePanel
- Sheet-style when attached to window
- Follows system theme
- Supports Quick Look preview
- Tags and favourites integration
### Windows
- Native File Open/Save dialogs
- Follows system theme
- Recent files integration
- Network location support
### Linux
- GTK file chooser
- Varies by desktop environment
- Follows desktop theme
- Recent files support
## Next Steps
<CardGrid>
<Card title="Message dialogs" icon="information">
Info, warning, and error dialogs.
[Learn More →](/features/dialogs/message)
</Card>
<Card title="Custom dialogs" icon="puzzle">
Create custom dialog windows.
[Learn More →](/features/dialogs/custom)
</Card>
<Card title="Bindings" icon="rocket">
Call Go functions from JavaScript.
[Learn More →](/features/bindings/methods)
</Card>
<Card title="Events" icon="star">
Use events for progress updates.
[Learn More →](/features/events/system)
</Card>
</CardGrid>
---
**Questions?** Ask in [Discord](https://discord.gg/JDdSxwjhGf) or check the [file dialog examples](https://github.com/wailsapp/wails/tree/v3-alpha/v3/examples/dialogs).