Pygame drawable text class fails to draw - python-3.x

Question

I have a class that represents a bit of text that can be drawn to the screen. This class is intended to be used in relation to a Window object that, when it is drawn, passes a subsurface of the surface it was given to the draw() function of the text element.
The window draws, but the text does not. Nor does it draw when I invoke the TextElement's draw() function directly. I've examined the code with a debugger, and the blit is definitely being done. I've also tried switching the font to "Arial" instead of letting Pygame grab the default.
import pygame
#Background and edge color of windows
global bgcolor
global bordercolor
global txtcolor
#Pygame font object that most text will be drawn in
global mainfont
#Defaults; code that imports us can change these.
#Black background with white borders & text
bgcolor=(0,0,0)
txtcolor=(255,255,255)
bordercolor=(255,255,255)
#This will give us whatever font Pygame is set up to use as default
if not __name__== "__main__":
#Font module needs to be initialized for this to work; it should be if we're imported, but won't if
#we're being executed directly.
mainfont=pygame.font.SysFont(None,12)
else:
mainfont=None
class Window:
"""The base UI class. Is more-or-less a way to draw an empty square onto the screen. Other things are derived from this.
Also usable in its own right as a way to manage groups of more complex elements by defining them as children of
a basic window."""
def __init__(self, rect):
self.rect=rect
#'children' of a window are drawn whenever it is drawn, unless their positions are outside the area of the window.
self.children=[]
def draw(self, surface):
"Draw this window to the given surface."
pygame.draw.rect(surface, bgcolor, self.rect)
#Draw non-filled rect with line width 4 as the border
pygame.draw.rect(surface, bordercolor, self.rect, 4)
self._draw_children(surface)
def _draw_children(self,surface):
"Call draw() on each of the children of this window. Intended to be called as part of an element's draw() function."
for thechild in self.children:
#We use a subsurface because we only want our child elements to be able to access the area inside this window.
thechild.draw(surface.subsurface(self.rect))
class TextElement(str):
"""A bit of static text that can be drawn to the screen. Intended to be used inside a Window, but can be drawn
straight to a surface. Immutable; use DynamicTextElement for text that can change and move."""
def __new__(cls,text,font,rect=pygame.Rect((0,0),(0,0))):
self=super().__new__(cls,text)
self.image=font.render(text,True,txtcolor)
self.rect=rect
return self
def __repr__(self):
return str.join("",("TextElement('",self,"')"))
def draw(self,surface):
self.image.blit(surface,self.rect.topleft)
class DynamicTextElement():
"""A bit of text whose text can be changed and that can be moved. Slower than TextElement."""
def __init__(self,text,font,rect):
self.text, self.font, self.rect = text, font, rect
def __repr__(self):
return str.join("",("DynamicTextElement('",self.text,"')"))
def draw(self,surface):
image=self.font.render(self.text,True,txtcolor)
image.blit(surface,self.rect.topleft)
if __name__ == '__main__':
pygame.init()
mainfont=pygame.font.SysFont(None,12)
screen=pygame.display.set_mode((800,600))
mywindow=Window(pygame.Rect(150,150,600,300))
mytext=TextElement("Hello world! This is static, immutable text!",mainfont,pygame.Rect((200,200),(100,100)))
mydyntext=DynamicTextElement("And this is dnyamic, movable text!",mainfont,pygame.Rect((200,230),(100,100)))
print(mytext.image)
mywindow.children.append(mytext)
clock=pygame.time.Clock()
while True:
pygame.event.pump()
clock.tick(60)
screen.fill((55,55,55))
mywindow.draw(screen)
mytext.draw(screen)
pygame.display.flip()
Any ideas?

Answer 1

You use
self.image.blit(surface, self.rect.topleft)
but should be
surface.blit(self.image, self.rect.topleft)
surface and self.image in wrong places.
You tried to draw surface on text.
You have the same problem in DynamicTextElement()
BTW: I use Python 2 so I had to use str
self = str.__new__(cls,text)
in place of super()
self = super().__new__(cls,text)