Experimental Style funcs for progress

Author: ptxmac

cmd/demo-progress/demo.go

@@ -4,6 +4,7 @@ import (
 	"flag"
 	"fmt"
 	"math/rand"
+	"strings"
 	"time"
 
 	"github.com/jedib0t/go-pretty/v6/progress"
@@ -145,6 +146,34 @@ func main() {
 	pw.Style().Visibility.Value = !*flagHideValue
 	pw.Style().Visibility.Pinned = *flagShowPinned
 
+	colors := []text.Colors{
+		{text.FgRed},
+		{text.FgGreen},
+		{text.FgYellow},
+		{text.FgBlue},
+		{text.FgMagenta},
+		{text.FgCyan},
+	}
+
+	pw.Style().CustomFuncs.TrackerDeterminate = func(value int64, total int64, maxLen int) string {
+		v := float64(value) / float64(total)
+		b := &strings.Builder{}
+		fmt.Fprintf(b, "[")
+		inner := maxLen - 2
+		for i := 0; i < inner; i++ {
+			delta := float64(i) / float64(inner)
+			colorIdx := delta * float64(len(colors))
+			color := colors[int(colorIdx)%len(colors)]
+			if delta < v {
+				fmt.Fprintf(b, "%s", color.Sprint("█"))
+			} else {
+				fmt.Fprintf(b, " ")
+			}
+		}
+		fmt.Fprintf(b, "]")
+		return b.String()
+	}
+
 	// call Render() in async mode; yes we don't have any trackers at the moment
 	go pw.Render()
 

progress/render.go

@@ -107,6 +107,10 @@ func (p *Progress) generateTrackerStr(t *Tracker, maxLen int, hint renderHint) s
 // generateTrackerStrDeterminate generates the tracker string for the case where
 // the Total value is known, and the progress percentage can be calculated.
 func (p *Progress) generateTrackerStrDeterminate(value int64, total int64, maxLen int) string {
+	if p.style.CustomFuncs.TrackerDeterminate != nil {
+		return p.style.CustomFuncs.TrackerDeterminate(value, total, maxLen)
+	}
+
 	pFinishedDots, pFinishedDotsFraction := 0.0, 0.0
 	pDotValue := float64(total) / float64(maxLen)
 	if pDotValue > 0 {
@@ -133,13 +137,13 @@ func (p *Progress) generateTrackerStrDeterminate(value int64, total int64, maxLe
 	if pFinishedStrLen < maxLen {
 		pUnfinished = strings.Repeat(p.style.Chars.Unfinished, maxLen-pFinishedStrLen)
 	}
-
+	
 	return p.style.Colors.Tracker.Sprintf("%s%s%s%s%s",
 		p.style.Chars.BoxLeft, pFinished, pInProgress, pUnfinished, p.style.Chars.BoxRight,
 	)
 }
 
-// generateTrackerStrDeterminate generates the tracker string for the case where
+// generateTrackerStrIndeterminate generates the tracker string for the case where
 // the Total value is unknown, and the progress percentage cannot be calculated.
 func (p *Progress) generateTrackerStrIndeterminate(maxLen int) string {
 	indicator := p.style.Chars.Indeterminate(maxLen)

progress/style.go

@@ -8,11 +8,12 @@ import (
 
 // Style declares how to render the Progress/Trackers.
 type Style struct {
-	Name       string          // name of the Style
-	Chars      StyleChars      // characters to use on the progress bar
-	Colors     StyleColors     // colors to use on the progress bar
-	Options    StyleOptions    // misc. options for the progress bar
-	Visibility StyleVisibility // show/hide components of the progress bar(s)
+	Name        string          // name of the Style
+	Chars       StyleChars      // characters to use on the progress bar
+	Colors      StyleColors     // colors to use on the progress bar
+	Options     StyleOptions    // misc. options for the progress bar
+	Visibility  StyleVisibility // show/hide components of the progress bar(s)
+	CustomFuncs StyleFunctions  // custom render functions for the progress bar
 }
 
 var (
@@ -215,3 +216,7 @@ var StyleVisibilityDefault = StyleVisibility{
 	TrackerOverall: false,
 	Value:          true,
 }
+
+type StyleFunctions struct {
+	TrackerDeterminate func(value int64, total int64, maxLen int) string
+}