Multicolor in TextView?

[monlie]

I would like to write a simple editor of scheme to learning SICP with my iPad. So I need to highlight some characters (such as keywords and brackets) in TextView. But it seems like I could only set a global font color for it.

[cvp]

See and try sample of @JonB here
It uses attributedText in Objective-C

Sample based on this code

# coding: utf-8
# set attributed text dor existing textview
# see JonB code at 
#     https://github.com/jsbain/objc_hacks/blob/master/attribtext2.py
import ui
from objc_util import *

class MyView(ui.View):
	def __init__(self):
		self.width = 300
		self.height = 300
		tv=ui.TextView(flex='wh',frame=self.bounds)
		tv.delegate = self
		self.add_subview(tv)
        tv.begin_editing()
		
		UIColor=ObjCClass('UIColor')
		self.UIred = UIColor.redColor()
		self.UIfont=ObjCClass('UIFont').fontWithName_size_('Courier',20)

		#set up objc instance		
		self.tvo=ObjCInstance(tv)
		
	def textview_did_change(self, textview):
		self.stro=ObjCClass('NSMutableAttributedString').alloc().initWithString_( textview.text)
		i = 0
		st = textview.text.find('[',i)
		l = 1
		while st >= 0:					
			self.stro.addAttribute_value_range_('NSBackgroundColor',self.UIred,NSRange(st,l))
			self.stro.addAttribute_value_range_(ObjCInstance(c_void_p.in_dll(c,'NSFontAttributeName')),self.UIfont,NSRange(st,l))
			self.setAttribs()
			i = st + 1
			st = textview.text.find('[',i)
		
	@on_main_thread
	#apparently this must be called on main thread for textview
	def setAttribs(self):
		self.tvo.setAllowsEditingTextAttributes_(True)
		self.tvo.setAttributedText_(self.stro)
		
v=MyView()
v.present('sheet')

It allows you to enter your text and it set the red color for all "[" found in it.