add support for NSPasteboard

[flexzuu]

This PR adds support for NSPasteboard. Currently it covers the basic read from and write to pasteboard operations.

I included the objc code that i used to get the constants as comment. If anyone knows how we can access them directly instead let me know. I would gladly replace it.

Also i did not include the constants NSFileContentsPboardType, NSFindPanelSearchOptionsPboardType Pasteboard types as they had different contents that i was not sure about.

In terms of testing, i use this as showcased in the example with string only for now and have not yet tested pictures or anything else.

Also i spend some time to get the original apple doc comments converted and linked in the relevant places. Not sure if we want to do this or not.

[progrium]

I love the links to relevant docs, I really wanted to do that. Hopefully others will continue or we can just make it part of the PR acceptance process.

Some other places I look for constant values, if the docs don't say, sometimes you can find out from .bridgesupport files.

[LinkinStars]

I want to read pictures from pasteboard.

gp := cocoa.NSPasteboard_GeneralPasteboard()

s := gp.Send("dataForType:",  core.NSString_FromString(cocoa.NSPasteboardTypePNG)).String()

I can read file info, but I don’t know how to save file.

I try to write like this, but I still can't save it as a picture correctly.
err := ioutil.WriteFile("1.png", []byte(s), 0666)

Do you have any good ideas?

@flexzuu

[flexzuu]

I will take a look

[electricbubble]

I make a little attempt.
I'm not good at it. 😔

[flexzuu]

I got it working:

package main

import "C"
import (
	"github.com/progrium/macdriver/cocoa"
	"github.com/progrium/macdriver/core"
	"io/ioutil"
	"unsafe"
)

func main() {
	// get general pasteboard
	gp := cocoa.NSPasteboard_GeneralPasteboard()


	data := gp.Send("dataForType:",  core.NSString_FromString(cocoa.NSPasteboardTypePNG))
	objcBytes := data.Get("bytes")
	length := data.Get("length")
	bs := C.GoBytes(unsafe.Pointer(objcBytes.Pointer()), C.int(length.Uint()))
	err := ioutil.WriteFile("/Users/jonas/Desktop/1.png", bs, 0666)
	if err != nil {
		panic(err)
	}
}

[flexzuu]

I will need to go now might open PR later with an example or some nicer api for length and bytes

[LinkinStars]

I tried. It works. Excellent!

[electricbubble]

I will need to go now might open PR later with an example or some nicer api for length and bytes

Maybe like this

func (pb NSPasteboard) DataForType(t NSPasteboardType) []byte {
	data := pb.Send("dataForType:",  core.NSString_FromString(t))
	objcBytes := data.Get("bytes")
	length := data.Get("length")
	return C.GoBytes(unsafe.Pointer(objcBytes.Pointer()), C.int(length.Uint()))
}

[flexzuu]

#31 is open and adds a bunch of utility to improve the workflow when using NSPasteboard