Clipboard Operations

Wails provides a unified clipboard API that works across all platforms. Copy and paste text with simple, consistent methods on Windows, macOS, and Linux.

Quick Start

// Copy text to clipboard
app.Clipboard.SetText("Hello, World!")

// Get text from clipboard
text, ok := app.Clipboard.Text()
if ok {
    fmt.Println("Clipboard:", text)
}

That’s it! Cross-platform clipboard access.

Copying Text

Basic Copy

success := app.Clipboard.SetText("Text to copy")
if !success {
    app.Logger.Error("Failed to copy to clipboard")
}

Returns: bool - true if successful, false otherwise

Copy from Service

type ClipboardService struct {
    app *application.App
}

func (c *ClipboardService) CopyToClipboard(text string) bool {
    return c.app.Clipboard.SetText(text)
}

Call from JavaScript:

import { CopyToClipboard } from './bindings/changeme/clipboardservice'

await CopyToClipboard("Text to copy")

Copy with Feedback

func copyWithFeedback(text string) {
    if app.Clipboard.SetText(text) {
        app.Dialog.Info().
            SetTitle("Copied").
            SetMessage("Text copied to clipboard!").
            Show()
    } else {
        app.Dialog.Error().
            SetTitle("Copy Failed").
            SetMessage("Failed to copy to clipboard.").
            Show()
    }
}

Pasting Text

Basic Paste

text, ok := app.Clipboard.Text()
if !ok {
    app.Logger.Error("Failed to read clipboard")
    return
}

fmt.Println("Clipboard text:", text)

Returns: (string, bool) - Text and success flag

Paste from Service

func (c *ClipboardService) PasteFromClipboard() string {
    text, ok := c.app.Clipboard.Text()
    if !ok {
        return ""
    }
    return text
}

Call from JavaScript:

import { PasteFromClipboard } from './bindings/changeme/clipboardservice'

const text = await PasteFromClipboard()
console.log("Pasted:", text)

Paste with Validation

func pasteText() (string, error) {
    text, ok := app.Clipboard.Text()
    if !ok {
        return "", errors.New("clipboard empty or unavailable")
    }
    
    // Validate
    if len(text) == 0 {
        return "", errors.New("clipboard is empty")
    }
    
    if len(text) > 10000 {
        return "", errors.New("clipboard text too large")
    }
    
    return text, nil
}

Complete Examples

Copy Button

Go:

type TextService struct {
    app *application.App
}

func (t *TextService) CopyText(text string) error {
    if !t.app.Clipboard.SetText(text) {
        return errors.New("failed to copy")
    }
    return nil
}

JavaScript:

import { CopyText } from './bindings/changeme/textservice'

async function copyToClipboard(text) {
    try {
        await CopyText(text)
        showNotification("Copied to clipboard!")
    } catch (error) {
        showError("Failed to copy: " + error)
    }
}

// Usage
document.getElementById('copy-btn').addEventListener('click', () => {
    const text = document.getElementById('text').value
    copyToClipboard(text)
})

Paste and Process

Go:

type DataService struct {
    app *application.App
}

func (d *DataService) PasteAndProcess() (string, error) {
    // Get clipboard text
    text, ok := d.app.Clipboard.Text()
    if !ok {
        return "", errors.New("clipboard unavailable")
    }
    
    // Process text
    processed := strings.TrimSpace(text)
    processed = strings.ToUpper(processed)
    
    return processed, nil
}

JavaScript:

import { PasteAndProcess } from './bindings/changeme/dataservice'

async function pasteAndProcess() {
    try {
        const result = await PasteAndProcess()
        document.getElementById('output').value = result
    } catch (error) {
        showError("Failed to paste: " + error)
    }
}

Copy Multiple Formats

type CopyService struct {
    app *application.App
}

func (c *CopyService) CopyAsPlainText(text string) bool {
    return c.app.Clipboard.SetText(text)
}

func (c *CopyService) CopyAsJSON(data interface{}) bool {
    jsonBytes, err := json.MarshalIndent(data, "", "  ")
    if err != nil {
        return false
    }
    return c.app.Clipboard.SetText(string(jsonBytes))
}

func (c *CopyService) CopyAsCSV(rows [][]string) bool {
    var buf bytes.Buffer
    writer := csv.NewWriter(&buf)
    
    for _, row := range rows {
        if err := writer.Write(row); err != nil {
            return false
        }
    }
    
    writer.Flush()
    return c.app.Clipboard.SetText(buf.String())
}

Clipboard Monitor

type ClipboardMonitor struct {
    app          *application.App
    lastText     string
    ticker       *time.Ticker
    stopChan     chan bool
}

func NewClipboardMonitor(app *application.App) *ClipboardMonitor {
    return &ClipboardMonitor{
        app:      app,
        stopChan: make(chan bool),
    }
}

func (cm *ClipboardMonitor) Start() {
    cm.ticker = time.NewTicker(1 * time.Second)
    
    go func() {
        for {
            select {
            case <-cm.ticker.C:
                cm.checkClipboard()
            case <-cm.stopChan:
                return
            }
        }
    }()
}

func (cm *ClipboardMonitor) Stop() {
    if cm.ticker != nil {
        cm.ticker.Stop()
    }
    cm.stopChan <- true
}

func (cm *ClipboardMonitor) checkClipboard() {
    text, ok := cm.app.Clipboard.Text()
    if !ok {
        return
    }
    
    if text != cm.lastText {
        cm.lastText = text
        cm.app.Event.Emit("clipboard-changed", text)
    }
}

Copy with History

type ClipboardHistory struct {
    app     *application.App
    history []string
    maxSize int
}

func NewClipboardHistory(app *application.App) *ClipboardHistory {
    return &ClipboardHistory{
        app:     app,
        history: make([]string, 0),
        maxSize: 10,
    }
}

func (ch *ClipboardHistory) Copy(text string) bool {
    if !ch.app.Clipboard.SetText(text) {
        return false
    }
    
    // Add to history
    ch.history = append([]string{text}, ch.history...)
    
    // Limit size
    if len(ch.history) > ch.maxSize {
        ch.history = ch.history[:ch.maxSize]
    }
    
    return true
}

func (ch *ClipboardHistory) GetHistory() []string {
    return ch.history
}

func (ch *ClipboardHistory) RestoreFromHistory(index int) bool {
    if index < 0 || index >= len(ch.history) {
        return false
    }
    
    return ch.app.Clipboard.SetText(ch.history[index])
}

Frontend Integration

Using Browser Clipboard API

For simple text, you can use the browser’s clipboard API:

// Copy
async function copyText(text) {
    try {
        await navigator.clipboard.writeText(text)
        console.log("Copied!")
    } catch (error) {
        console.error("Copy failed:", error)
    }
}

// Paste
async function pasteText() {
    try {
        const text = await navigator.clipboard.readText()
        return text
    } catch (error) {
        console.error("Paste failed:", error)
        return ""
    }
}

Note: Browser clipboard API requires HTTPS or localhost, and user permission.

Using Wails Clipboard

For system-wide clipboard access:

import { CopyToClipboard, PasteFromClipboard } from './bindings/changeme/clipboardservice'

// Copy
async function copy(text) {
    const success = await CopyToClipboard(text)
    if (success) {
        console.log("Copied!")
    }
}

// Paste
async function paste() {
    const text = await PasteFromClipboard()
    return text
}

Best Practices

✅ Do

Check return values - Handle failures gracefully
Provide feedback - Let users know copy succeeded
Validate pasted text - Check format and size
Use appropriate method - Browser API vs Wails API
Handle empty clipboard - Check before using
Trim whitespace - Clean pasted text

❌ Don’t

Don’t ignore failures - Always check success
Don’t copy sensitive data - Clipboard is shared
Don’t assume format - Validate pasted data
Don’t poll too frequently - If monitoring clipboard
Don’t copy large data - Use files instead
Don’t forget security - Sanitise pasted content

Platform Differences

macOS

Uses NSPasteboard
Supports rich text (future)
System-wide clipboard
Clipboard history (system feature)

Windows

Uses Windows Clipboard API
Supports multiple formats (future)
System-wide clipboard
Clipboard history (Windows 10+)

Linux

Uses X11/Wayland clipboard
Primary and clipboard selections
Varies by desktop environment
May require clipboard manager

Limitations

Current Version

Text only - Images not yet supported
No format detection - Plain text only
No clipboard events - Must poll for changes
No clipboard history - Implement yourself

Future Features

Image support
Rich text support
Multiple formats
Clipboard change events
Clipboard history API

Next Steps

Bindings

Call Go functions from JavaScript.

Learn More →

Events

Use events for clipboard notifications.

Learn More →

dialogs

Show copy/paste feedback.

Learn More →

Services

Organise clipboard code.

Learn More →

Questions? Ask in Discord or check the clipboard examples.