nasin/README.md

# nasin

[![Go Reference](https://pkg.go.dev/badge/git.tebibyte.media/tomo/nasin.svg)](https://pkg.go.dev/git.tebibyte.media/tomo/nasin)

Nasin builds an application framework on top of Tomo to ease and encourage the
development of consistent and stable application software. It has these
wonderful features, and more:

- Use the Application interface to create applications with relatively low
  boilerplate
- CLI argument parsing and URI opening
- Automatic setup/teardown of the backend
- Advanced configuration system that can watch config files for changes
- Default style and icon set, as well as a fully featured stylesheet language
  for creating custom styles, and support for XDG icon themes

## Getting Started
Here is a basic "hello world" application, with explanations as comments:
```go
package main

import "image"
import "git.tebibyte.media/tomo/nasin"
import "git.tebibyte.media/tomo/objects"
import "git.tebibyte.media/tomo/objects/layouts"

func main () {
	nasin.RunApplication(new(Application))
}

type Application struct { }

// Describe returns the application's name and ID, and optionally what type of
// application it is.
func (this *Application) Describe () nasin.ApplicationDescription {
	return nasin.ApplicationDescription {
		// This is the name of the application. New application windows
		// will have this as their title by default.
		Name: "Example",
		// This is a "well-known" name, which typically is a domain name
		// owned by the application author.
		ID: "com.example.Example",
	}
}

// Init performs initial setup of the application. Since this is a single-window
// application that doesn't open any files, we create the window here.
func (this *Application) Init () error {
	// Passing an empty rectangle when creating a new window will cause it
	// to auto-expand to fit the minimum size of its contents.
	window, err := nasin.NewApplicationWindow(this, image.Rectangle { })
	if err != nil { return err }
	// Here we create a new container with a basic vertical layout, place a
	// text label that says "Hello world!" in it, and set it as the root
	// object of the window.
	window.SetRoot(objects.NewOuterContainer (
		layouts.ContractVertical,
		objects.NewLabel("Hello world!")))
	window.SetVisible(true)
	// Nasin will not exit until all windows it is "waiting for" have
	// been closed.
	nasin.WaitFor(window)
	return nil
}

// Stop cleanly closes things like system resources or background tasks. We do
// not have any here, so nothing is done.
func (this *Application) Stop () { }
```

To learn more, take a look at the [examples](examples) directory and the
[online documentation](https://pkg.go.dev/git.tebibyte.media/tomo/nasin).

## Related Repositories
- [Tomo API](https://git.tebibyte.media/tomo/tomo): The API that all other parts
  of the toolkit agree on
- [Objects](https://git.tebibyte.media/tomo/objects): A standard collection of
  re-usable objects and other GUI components
- [Backend](https://git.tebibyte.media/tomo/backend): The software responsible
  for managing and rendering things behind the scenes