CS21: Using the Graphics Library

from graphics import *

# creates new GraphWin object, 500x500 pixels in size
win = GraphWin("My GUI Program", 500, 500)

# set the background color to blue   
win.setBackground("blue")             
  
# creates a new Circle object centered at 50,50 with a radius of 20 pixels
circ = Circle(Point(50,50), 20) 

# invoke the setFill method of the Circle object refered to by circ 
circ.setFill("red")             

# draw the circ object to the GraphWin win
circ.draw(win)                  

$ python
>>> import graphics
>>> help(graphics)

$ python
>>> from colorPicker import *
>>> colorPicker()
# then click on a color and its name will show up in the python interpreter

There is a lot to sort through in the graphics library help documentation, so to simplify things a bit, here is some information about the GraphWin object and some of the Graphics objects you may want to use (section 5.8 of the Zelle text also contains a more complete reference for the classes in the graphics library):

class GraphWin
--------------

        GraphWin(title, width, height)

        close()
        # update drawing to graphics window
        flush()  

        getHeight()
        getWidth()

        # wait for mouse click and return Point representing clicked location
        getMouse() 

        # color could be something like "red"
        setBackground(color)   

        # Sets the coordinate system of the window so that the lower
        # left corner is at (xll, yll) and the upper right corner is
        # at (xur, yur)
        setCoords(xll, yll, xur, yur)


class Point
------------

     Point(x, y)

     clone()    # create a new Point object that is an exact copy of this one
     getX()     # the int value of the Point's x-coordinate
     getY()     # the int value of the Point's y-coordinate

     ----------------------- Methods commone to all Graphics Object classes:

     draw(graphwin):    # Draw the object in graphwin, which should be a 
                        # GraphWin object.  A GraphicsObject may only be drawn 
                        # into one window. 
     move(dx, dy):      # move object dx units in x and dy units in y direction
     setFill(color):    # Set interior color to color
     setOutline(color): # Set outline color to color
     setWidth(width):   # Set line weight to width
     undraw():          # Undraw the object (i.e. hide it). 


class Line
----------

     Line(p1, p2)   # p1 and p2 are the end Points of the line

     clone()
     setArrow(option)   
     getCenter()    # returns a Point object corresponding to the Line's center
     getP1()        # get one end-point Point object
     getP2()        # get the other Point object

     draw(graphwin)
     move(dx, dy)   # move the Line dx pixels on the x-axis and dy on the y-axis
     setFill(color)
     setOutline(color)
     setWidth(width) 

class Rectangle
---------------

     Rectangle( p1, p2) # p1 and p2 are points for upper left lower rt

     clone()
     getCenter()        # returns a Point object corresponding to the center
     getP1()            # returns the upper left corner Point
     getP2()            # returns the lower right corner Point

     draw(graphwin)
     move(dx, dy)	# move the Rectangle dx pixels on x-axis, dy on y-axis
     setFill(color)
     setOutline(color)
     setWidth(width)    # set the width, in pixels of the outline
     undraw()


class Circle
----------
     Circle(p1, radius) # p1 is a Point at the center of the circle, radius is an int

     clone()
     getCenter()        # returns the Point object describing the Circle's center
     getRadius()        # returns the int value of the Circle's radius
     getP1()            # returns a clone of the corresponding corner of the
     getP2()	        # circle's bounding box (opposite corners of bounding square)

     draw(graphwin)
     move(dx, dy)       # distance in x and y axis to move the circle
     setFill(color)   
     setOutline(color)
     setWidth(width)    # the width of the circle's outline
     undraw()


class Oval
----------
     Oval(p1, p2)       # p1 and p2 are Points of opposite corners of bounding rectangle 

     clone()
     getCenter()
     getP1()
     getP2()

     draw(graphwin)
     move(dx, dy)
     setFill(color)
     setOutline(color)
     setWidth(width)

class Polygon
-------------

     # ex. triangle: Polygon ([Point(10,20), Point(30,40), Point(10,60)])
     Polygon()
        

     getPoints()  # return a list of Points in the polygon
     clone()

     draw(graphwin)
     move(dx, dy)
     setFill(color)
     setOutline(color)
     setWidth(width)
     undraw()


class Text
----------
     Text(p, text)       # p is center point and text is string
    
     clone()
     getText()
     setText(text)
     setTextColor(color)
     setFace(family)     # set font face, ex. "arial" "courier"
     setSize(size)       # set font size (5-36 are legal)    
     setStyle(style)     # set font style  ex.  "bold" "italic"

     draw(graphwin)
     move(dx, dy)
     setFill(color)
     setOutline(color)
     setWidth(width)
     undraw()


class Entry: GUI object into which user can type text
------------

     Entry(pt, width)     # pt is anchor Point (center) width is an int

     getAnchor()          # returns the center Point
     getText()            # returns the current text
     setText(string)      # sets the text to string
     setSize(point)       # sets the found size (5-36 are legal)
     setStyle(style)      # sets the font style
     setTextColor(color)  # sets the text color

     draw(graphwin)
     move(dx, dy)
     setFill(color)
     setOutline(color)
     setWidth(width)
     undraw()