Add a keyboard abstraction so Fyne is input-API agnostic

driver/efl/window.go

@@ -254,7 +254,28 @@ func onWindowKeyDown(ew C.Ecore_Window, info *C.Ecore_Event_Key) {
 
 	ev := new(fyne.KeyEvent)
 	ev.String = C.GoString(info.string)
-	ev.Name = C.GoString(info.keyname)
+	switch C.GoString(info.keyname) {
+	case "Shift_L":
+		fallthrough
+	case "Shift_R":
+		ev.Name = fyne.KeyShift
+	case "Control_L":
+		fallthrough
+	case "Control_R":
+		ev.Name = fyne.KeyControl
+	case "Alt_L":
+		fallthrough
+	case "Alt_R":
+		ev.Name = fyne.KeyAlt
+	case "Super_L":
+		fallthrough
+	case "Super_R":
+		ev.Name = fyne.KeySuper
+
+	default:
+		ev.Name = fyne.KeyName(C.GoString(info.keyname))
+	}
+
 	if (info.modifiers & C.ECORE_EVENT_MODIFIER_SHIFT) != 0 {
 		ev.Modifiers |= fyne.ShiftModifier
 	}

driver/gl/window.go

@@ -242,16 +242,97 @@ func (w *window) mouseClicked(viewport *glfw.Window, button glfw.MouseButton, ac
 	}
 }
 
-func keyToName(key glfw.Key) string {
+func keyToName(key glfw.Key) fyne.KeyName {
 	switch key {
+	// printable
+	case glfw.KeySpace:
+		return fyne.KeySpace
+
+	// non-printable
+	case glfw.KeyEscape:
+		return fyne.KeyEscape
+	case glfw.KeyEnter:
+		return fyne.KeyReturn
+	case glfw.KeyTab:
+		return fyne.KeyTab
+	case glfw.KeyBackspace:
+		return fyne.KeyBackspace
+	case glfw.KeyInsert:
+		return fyne.KeyInsert
+	case glfw.KeyDelete:
+		return fyne.KeyDelete
 	case glfw.KeyRight:
-		return "Right"
+		return fyne.KeyRight
 	case glfw.KeyLeft:
-		return "Left"
-	case glfw.KeyUp:
-		return "Up"
+		return fyne.KeyLeft
 	case glfw.KeyDown:
-		return "Down"
+		return fyne.KeyDown
+	case glfw.KeyUp:
+		return fyne.KeyUp
+	case glfw.KeyPageUp:
+		return fyne.KeyPageUp
+	case glfw.KeyPageDown:
+		return fyne.KeyPageDown
+	case glfw.KeyHome:
+		return fyne.KeyHome
+	case glfw.KeyEnd:
+		return fyne.KeyEnd
+
+	case glfw.KeyF1:
+		return fyne.KeyF1
+	case glfw.KeyF2:
+		return fyne.KeyF2
+	case glfw.KeyF3:
+		return fyne.KeyF3
+	case glfw.KeyF4:
+		return fyne.KeyF4
+	case glfw.KeyF5:
+		return fyne.KeyF5
+	case glfw.KeyF6:
+		return fyne.KeyF6
+	case glfw.KeyF7:
+		return fyne.KeyF7
+	case glfw.KeyF8:
+		return fyne.KeyF8
+	case glfw.KeyF9:
+		return fyne.KeyF9
+	case glfw.KeyF10:
+		return fyne.KeyF10
+	case glfw.KeyF11:
+		return fyne.KeyF11
+	case glfw.KeyF12:
+		return fyne.KeyF12
+
+	case glfw.KeyLeftShift:
+		fallthrough
+	case glfw.KeyRightShift:
+		return fyne.KeyShift
+	case glfw.KeyLeftControl:
+		fallthrough
+	case glfw.KeyRightControl:
+		return fyne.KeyControl
+	case glfw.KeyLeftAlt:
+		fallthrough
+	case glfw.KeyRightAlt:
+		return fyne.KeyAlt
+	case glfw.KeyLeftSuper:
+		fallthrough
+	case glfw.KeyRightSuper:
+		return fyne.KeySuper
+	case glfw.KeyMenu:
+		return fyne.KeyMenu
+
+	case glfw.KeyKPEnter:
+		return fyne.KeyEnter
+	}
+	return ""
+}
+
+func charToName(char rune) fyne.KeyName {
+	switch char {
+	case ' ':
+		return fyne.KeySpace
+
 	}
 	return ""
 }
@@ -260,6 +341,9 @@ func (w *window) keyPressed(viewport *glfw.Window, key glfw.Key, scancode int, a
 	if w.canvas.Focused() == nil && w.canvas.onKeyDown == nil {
 		return
 	}
+	if action != glfw.Press { // ignore key up
+		return
+	}
 
 	if key <= glfw.KeyWorld1 { // filter printable characters handled in charModInput
 		return
@@ -291,7 +375,7 @@ func (w *window) charModInput(viewport *glfw.Window, char rune, mods glfw.Modifi
 	}
 
 	ev := new(fyne.KeyEvent)
-	ev.Name = string(char)
+	ev.Name = charToName(char)
 	ev.String = string(char)
 	if (mods & glfw.ModShift) != 0 {
 		ev.Modifiers |= fyne.ShiftModifier

event.go

@@ -4,7 +4,7 @@ package fyne
 type KeyEvent struct {
 	String string
 
-	Name      string
+	Name      KeyName
 	Modifiers Modifier
 }
 

key.go

@@ -1,5 +1,88 @@
 package fyne
 
+// KeyName represents the name of a key that has been pressed (or released)
+type KeyName string
+
+const (
+	// KeyUnnamed is used when the key does not have a name (check the key string for a printable version)
+	KeyUnnamed = ""
+
+	// Printable keys
+
+	// KeySpace name can also be checked with KeyEvent.String == " "
+	KeySpace = "Space"
+
+	// Non-printable keys
+
+	// KeyEscape is the "esc" key
+	KeyEscape = "Escape"
+	// KeyReturn is the carriage return (main keyboard)
+	KeyReturn = "Return"
+	// KeyTab is the tab advance key
+	KeyTab = "Tab"
+	// KeyBackspace is the delete-before-cursor key
+	KeyBackspace = "BackSpace"
+	// KeyInsert is the insert mode key
+	KeyInsert = "Insert"
+	// KeyDelete is the delete-after-cursor key
+	KeyDelete = "Delete"
+	// KeyRight is the right arrow key
+	KeyRight = "Right"
+	// KeyLeft is the left arrow key
+	KeyLeft = "Left"
+	// KeyDown is the down arrow key
+	KeyDown = "Down"
+	// KeyUp is the up arrow key
+	KeyUp = "Up"
+	// KeyPageUp is the page up num-pad key
+	KeyPageUp = "Prior"
+	// KeyPageDown is the page down num-pad key
+	KeyPageDown = "Next"
+	// KeyHome is the line-home key
+	KeyHome = "Home"
+	// KeyEnd is the line-end key
+	KeyEnd = "End"
+
+	// KeyF1 is the first function key
+	KeyF1 = "F1"
+	// KeyF2 is the second function key
+	KeyF2 = "F2"
+	// KeyF3 is the third function key
+	KeyF3 = "F3"
+	// KeyF4 is the fourth function key
+	KeyF4 = "F4"
+	// KeyF5 is the fifth function key
+	KeyF5 = "F5"
+	// KeyF6 is the sixth function key
+	KeyF6 = "F6"
+	// KeyF7 is the seventh function key
+	KeyF7 = "F7"
+	// KeyF8 is the eighth function key
+	KeyF8 = "F8"
+	// KeyF9 is the ninth function key
+	KeyF9 = "F9"
+	// KeyF10 is the tenth function key
+	KeyF10 = "F10"
+	// KeyF11 is the eleventh function key
+	KeyF11 = "F11"
+	// KeyF12 is the twelfth function key
+	KeyF12 = "F12"
+
+	// KeyEnter is the enter/ return key (keypad)
+	KeyEnter = "KP_Enter"
+
+	// KeyShift represents the left or right shift key
+	KeyShift = "Shift"
+	// KeyControl represents the left or right control key
+	KeyControl = "Control"
+	// KeyAlt represents the left or right alt key
+	KeyAlt = "Alt"
+	// KeySuper represents the left or right "Windows" key (or "Command" key on macOS)
+	KeySuper = "Super"
+	// KeyMenu represents the left or right menu / application key
+	KeyMenu = "Menu"
+)
+
 // Modifier captures any key modifiers (shift etc) pressed during this key event
 type Modifier int
 

widget/entry.go

@@ -157,7 +157,7 @@ func (e *Entry) Focused() bool {
 
 // OnKeyDown receives key input events when the Entry widget is focused.
 func (e *Entry) OnKeyDown(key *fyne.KeyEvent) {
-	if key.Name == "BackSpace" {
+	if key.Name == fyne.KeyBackspace {
 		if len(e.Text) == 0 || (e.CursorColumn == 0 && e.CursorRow == 0) {
 			return
 		}
@@ -176,7 +176,7 @@ func (e *Entry) OnKeyDown(key *fyne.KeyEvent) {
 		}
 
 		e.SetText(substr)
-	} else if key.Name == "Delete" {
+	} else if key.Name == fyne.KeyDelete {
 		texts := e.label().renderer.(*labelRenderer).texts
 		if len(e.Text) == 0 || (e.CursorRow == len(texts)-1 && e.CursorColumn == len(texts[e.CursorRow].Text)) {
 			return
@@ -187,35 +187,35 @@ func (e *Entry) OnKeyDown(key *fyne.KeyEvent) {
 		substr := fmt.Sprintf("%s%s", string(runes[:pos]), string(runes[pos+1:]))
 
 		e.SetText(substr)
-	} else if key.Name == "Return" {
+	} else if key.Name == fyne.KeyReturn {
 		e.insertAtCursor("\n")
 
 		e.CursorColumn = 0
 		e.CursorRow++
-	} else if key.Name == "Up" {
+	} else if key.Name == fyne.KeyUp {
 		if e.CursorRow > 0 {
 			e.CursorRow--
 		}
 
 		if e.CursorColumn > e.label().RowLength(e.CursorRow) {
 			e.CursorColumn = e.label().RowLength(e.CursorRow)
 		}
-	} else if key.Name == "Down" {
+	} else if key.Name == fyne.KeyDown {
 		if e.CursorRow < e.label().Rows()-1 {
 			e.CursorRow++
 		}
 
 		if e.CursorColumn > e.label().RowLength(e.CursorRow) {
 			e.CursorColumn = e.label().RowLength(e.CursorRow)
 		}
-	} else if key.Name == "Left" {
+	} else if key.Name == fyne.KeyLeft {
 		if e.CursorColumn > 0 {
 			e.CursorColumn--
 		} else if e.CursorRow > 0 {
 			e.CursorRow--
 			e.CursorColumn = e.label().RowLength(e.CursorRow)
 		}
-	} else if key.Name == "Right" {
+	} else if key.Name == fyne.KeyRight {
 		if e.CursorColumn < e.label().RowLength(e.CursorRow) {
 			e.CursorColumn++
 		} else if e.CursorRow < e.label().Rows()-1 {