data/bidning: Rewrite xToString with generics

fyne-io · Jan 31, 2025 · 4db320f · 4db320f
1 parent 4e77e09
commit 4db320f
Showing 3 changed files with 99 additions and 149 deletions.
diff --git a/data/binding/convert.go b/data/binding/convert.go
@@ -1,6 +1,3 @@
-// auto-generated
-// **** THIS FILE IS AUTO-GENERATED, PLEASE DO NOT EDIT IT **** //
-
 package binding
 
 import (
@@ -9,31 +6,13 @@ import (
 	"fyne.io/fyne/v2"
 )
 
-func internalFloatToInt(val float64) (int, error) {
-	return int(val), nil
-}
-
-func internalIntToFloat(val int) (float64, error) {
-	return float64(val), nil
-}
-
-type stringFromBool struct {
-	base
-
-	format string
-
-	from Bool
-}
-
 // BoolToString creates a binding that connects a Bool data item to a String.
 // Changes to the Bool will be pushed to the String and setting the string will parse and set the
 // Bool if the parse was successful.
 //
 // Since: 2.0
 func BoolToString(v Bool) String {
-	str := &stringFromBool{from: v}
-	v.AddListener(str)
-	return str
+	return toStringComparable[bool](v, formatBool, parseBool)
 }
 
 // BoolToStringWithFormat creates a binding that connects a Bool data item to a String and is
@@ -42,72 +21,7 @@ func BoolToString(v Bool) String {
 //
 // Since: 2.0
 func BoolToStringWithFormat(v Bool, format string) String {
-	if format == "%t" { // Same as not using custom formatting.
-		return BoolToString(v)
-	}
-
-	str := &stringFromBool{from: v, format: format}
-	v.AddListener(str)
-	return str
-}
-
-func (s *stringFromBool) Get() (string, error) {
-	val, err := s.from.Get()
-	if err != nil {
-		return "", err
-	}
-
-	if s.format != "" {
-		return fmt.Sprintf(s.format, val), nil
-	}
-
-	return formatBool(val), nil
-}
-
-func (s *stringFromBool) Set(str string) error {
-	var val bool
-	if s.format != "" {
-		safe := stripFormatPrecision(s.format)
-		n, err := fmt.Sscanf(str, safe+" ", &val) // " " denotes match to end of string
-		if err != nil {
-			return err
-		}
-		if n != 1 {
-			return errParseFailed
-		}
-	} else {
-		new, err := parseBool(str)
-		if err != nil {
-			return err
-		}
-		val = new
-	}
-
-	old, err := s.from.Get()
-	if err != nil {
-		return err
-	}
-	if val == old {
-		return nil
-	}
-	if err = s.from.Set(val); err != nil {
-		return err
-	}
-
-	queueItem(s.DataChanged)
-	return nil
-}
-
-func (s *stringFromBool) DataChanged() {
-	s.trigger()
-}
-
-type stringFromFloat struct {
-	base
-
-	format string
-
-	from Float
+	return toStringWithFormatComparable[bool](v, format, "%t", formatBool, parseBool)
 }
 
 // FloatToString creates a binding that connects a Float data item to a String.
@@ -116,9 +30,7 @@ type stringFromFloat struct {
 //
 // Since: 2.0
 func FloatToString(v Float) String {
-	str := &stringFromFloat{from: v}
-	v.AddListener(str)
-	return str
+	return toStringComparable[float64](v, formatFloat, parseFloat)
 }
 
 // FloatToStringWithFormat creates a binding that connects a Float data item to a String and is
@@ -127,64 +39,7 @@ func FloatToString(v Float) String {
 //
 // Since: 2.0
 func FloatToStringWithFormat(v Float, format string) String {
-	if format == "%f" { // Same as not using custom formatting.
-		return FloatToString(v)
-	}
-
-	str := &stringFromFloat{from: v, format: format}
-	v.AddListener(str)
-	return str
-}
-
-func (s *stringFromFloat) Get() (string, error) {
-	val, err := s.from.Get()
-	if err != nil {
-		return "", err
-	}
-
-	if s.format != "" {
-		return fmt.Sprintf(s.format, val), nil
-	}
-
-	return formatFloat(val), nil
-}
-
-func (s *stringFromFloat) Set(str string) error {
-	var val float64
-	if s.format != "" {
-		safe := stripFormatPrecision(s.format)
-		n, err := fmt.Sscanf(str, safe+" ", &val) // " " denotes match to end of string
-		if err != nil {
-			return err
-		}
-		if n != 1 {
-			return errParseFailed
-		}
-	} else {
-		new, err := parseFloat(str)
-		if err != nil {
-			return err
-		}
-		val = new
-	}
-
-	old, err := s.from.Get()
-	if err != nil {
-		return err
-	}
-	if val == old {
-		return nil
-	}
-	if err = s.from.Set(val); err != nil {
-		return err
-	}
-
-	queueItem(s.DataChanged)
-	return nil
-}
-
-func (s *stringFromFloat) DataChanged() {
-	s.trigger()
+	return toStringWithFormatComparable[float64](v, format, "%f", formatFloat, parseFloat)
 }
 
 type intToFloat struct {

diff --git a/data/binding/convert_helper.go b/data/binding/convert_helper.go
@@ -101,3 +101,11 @@ func formatFloat(in float64) string {
 func formatInt(in int) string {
 	return strconv.FormatInt(int64(in), 10)
 }
+
+func internalFloatToInt(val float64) (int, error) {
+	return int(val), nil
+}
+
+func internalIntToFloat(val int) (float64, error) {
+	return float64(val), nil
+}
diff --git a/data/binding/generic.go b/data/binding/generic.go
@@ -1,6 +1,7 @@
 package binding
 
 import (
+	"fmt"
 	"sync/atomic"
 
 	"fyne.io/fyne/v2"
@@ -700,3 +701,89 @@ func (t *boundExternalTreeItem[T]) setIfChanged(val T) error {
 	t.trigger()
 	return nil
 }
+
+func toString[T any](v bindableItem[T], formatter func(T) string, comparator func(T, T) bool, parser func(string) (T, error)) *stringFrom[T] {
+	str := &stringFrom[T]{from: v, formatter: formatter, comparator: comparator, parser: parser}
+	v.AddListener(str)
+	return str
+}
+
+func toStringComparable[T bool | float64 | int](v bindableItem[T], formatter func(T) string, parser func(string) (T, error)) *stringFrom[T] {
+	return toString(v, formatter, func(t1, t2 T) bool { return t1 == t2 }, parser)
+}
+
+func toStringWithFormat[T any](v bindableItem[T], format, defaultFormat string, formatter func(T) string, comparator func(T, T) bool, parser func(string) (T, error)) String {
+	str := toString(v, formatter, comparator, parser)
+	if format != defaultFormat { // Same as not using custom formatting.
+		str.format = format
+	}
+
+	return str
+}
+
+func toStringWithFormatComparable[T bool | float64 | int](v bindableItem[T], format, defaultFormat string, formatter func(T) string, parser func(string) (T, error)) String {
+	return toStringWithFormat(v, format, defaultFormat, formatter, func(t1, t2 T) bool { return t1 == t2 }, parser)
+}
+
+type stringFrom[T any] struct {
+	base
+
+	format string
+
+	formatter  func(T) string
+	comparator func(T, T) bool
+	parser     func(string) (T, error)
+
+	from bindableItem[T]
+}
+
+func (s *stringFrom[T]) Get() (string, error) {
+	val, err := s.from.Get()
+	if err != nil {
+		return "", err
+	}
+
+	if s.format != "" {
+		return fmt.Sprintf(s.format, val), nil
+	}
+
+	return s.formatter(val), nil
+}
+
+func (s *stringFrom[T]) Set(str string) error {
+	var val T
+	if s.format != "" {
+		safe := stripFormatPrecision(s.format)
+		n, err := fmt.Sscanf(str, safe+" ", &val) // " " denotes match to end of string
+		if err != nil {
+			return err
+		}
+		if n != 1 {
+			return errParseFailed
+		}
+	} else {
+		new, err := s.parser(str)
+		if err != nil {
+			return err
+		}
+		val = new
+	}
+
+	old, err := s.from.Get()
+	if err != nil {
+		return err
+	}
+	if s.comparator(val, old) {
+		return nil
+	}
+	if err = s.from.Set(val); err != nil {
+		return err
+	}
+
+	queueItem(s.DataChanged)
+	return nil
+}
+
+func (s *stringFrom[T]) DataChanged() {
+	s.trigger()
+}