# Terminal User Interface Widgets in Go

Gowid provides widgets and a framework for making terminal user interfaces. It's written in Go and inspired by urwid.

Widgets out-of-the-box include:

• input components like button, checkbox and an editable text field with support for passwords
• layout components for arranging widgets in columns, rows and a grid
• structured components - a tree, an infinite list and a table
• pre-canned widgets - a progress bar, a modal dialog, a bar graph and a menu
• a VT220-compatible terminal widget, heavily cribbed from urwid :smiley:

All widgets support interaction with the mouse when the terminal allows.

Gowid is built on top of the fantastic tcell package.

There are many alternatives to gowid - see Similar Projects

The most developed gowid application is currently termshark, a terminal UI for tshark.

Installation

go get github.com/gcla/gowid/...

Examples

Make sure $GOPATH/bin is in your PATH (or ~/go/bin if GOPATH isn't set), then tab complete "gowid-" e.g.

gowid-fib

Here is a port of urwid's palette example:

Here is urwid's graph example:

And urwid's fibonacci example:

A demonstration of gowid's terminal widget, a port of urwid's terminal widget:

Finally, here is an animation of termshark in action:

Hello World

This example is an attempt to mimic urwid's "Hello World" example.

package main

import (
    "github.com/gcla/gowid"
    "github.com/gcla/gowid/widgets/divider"
    "github.com/gcla/gowid/widgets/pile"
    "github.com/gcla/gowid/widgets/styled"
    "github.com/gcla/gowid/widgets/text"
    "github.com/gcla/gowid/widgets/vpadding"
)

//======================================================================

func main() {

    palette := gowid.Palette{
        "banner":  gowid.MakePaletteEntry(gowid.ColorWhite, gowid.MakeRGBColor("#60d")),
        "streak":  gowid.MakePaletteEntry(gowid.ColorNone, gowid.MakeRGBColor("#60a")),
        "inside":  gowid.MakePaletteEntry(gowid.ColorNone, gowid.MakeRGBColor("#808")),
        "outside": gowid.MakePaletteEntry(gowid.ColorNone, gowid.MakeRGBColor("#a06")),
        "bg":      gowid.MakePaletteEntry(gowid.ColorNone, gowid.MakeRGBColor("#d06")),
    }

    div := divider.NewBlank()
    outside := styled.New(div, gowid.MakePaletteRef("outside"))
    inside := styled.New(div, gowid.MakePaletteRef("inside"))

    helloworld := styled.New(
        text.NewFromContentExt(
            text.NewContent([]text.ContentSegment{
                text.StyledContent("Hello World", gowid.MakePaletteRef("banner")),
            }),
            text.Options{
                Align: gowid.HAlignMiddle{},
            },
        ),
        gowid.MakePaletteRef("streak"),
    )

    f := gowid.RenderFlow{}

    view := styled.New(
        vpadding.New(
            pile.New([]gowid.IContainerWidget{
                &gowid.ContainerWidget{IWidget: outside, D: f},
                &gowid.ContainerWidget{IWidget: inside, D: f},
                &gowid.ContainerWidget{IWidget: helloworld, D: f},
                &gowid.ContainerWidget{IWidget: inside, D: f},
                &gowid.ContainerWidget{IWidget: outside, D: f},
            }),
            gowid.VAlignMiddle{},
            f),
        gowid.MakePaletteRef("bg"),
    )

    app, _ := gowid.NewApp(gowid.AppArgs{
        View:    view,
        Palette: &palette,
    })

    app.SimpleMainLoop()
}

Running the example above displays this:

Documentation

• The beginnings of a tutorial
• A list of most of the widgets
• Some FAQs (which I guessed at...)
• Some gowid programming tricks

Similar Projects

Gowid is late to the TUI party. There are many options from which to choose - please read https://appliedgo.net/tui/ for a nice summary for the Go language. Here is a selection:

• urwid - one of the oldest, for those working in python
• tview - active, polished, concise, lots of widgets, Go
• termui - focus on graphing and dataviz, Go
• gocui - focus on layout, good input options, mouse support, Go
• clui - active, many widgets, mouse support, Go
• tui-go - QT-inspired, experimental, nice examples, Go

Dependencies

Gowid depends on these great open-source packages:

• urwid - not a Go-dependency, but the model for most of gowid's design
• tcell - a cell based view for text terminals, like xterm, inspired by termbox
• asciigraph - lightweight ASCII line-graphs for Go
• logrus - structured pluggable logging for Go
• testify - tools for testifying that your code will behave as you intend

Contact

• The author - Graham Clark (grclark@gmail.com)

License