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8.10. Canvas line objects

In general, a line can consist of any number of segments connected end to end, and each segment can be straight or curved. To create a canvas line object on a canvas C, use:

    id = C.create_line(x0, y0, x1, y1, ..., xn, yn, option, ...)

The line goes through the series of points (x0, y0), (x1, y1), … (xn, yn). Options include:

Table 10. Canvas line options

activedash These options specify the dash, fill, stipple, and width values to be used when the line is active, that is, when the mouse is over it.
arrow The default is for the line to have no arrowheads. Use arrow=tk.FIRST to get an arrowhead at the (x0, y0) end of the line. Use arrow=tk.LAST to get an arrowhead at the far end. Use arrow=tk.BOTH for arrowheads at both ends.
arrowshape A tuple (d1, d2, d3) that describes the shape of the arrowheads added by the arrow option. Default is (8,10,3).

capstyle You can specify the shape of the ends of the line with this option; see Section 5.12, “Cap and join styles”. The default option is tk.BUTT.
dash To produce a dashed line, specify this option; see Section 5.13, “Dash patterns”. The default appearance is a solid line.
dashoffset If you specify a dash pattern, the default is to start the specified pattern at the beginning of the line. The dashoffset option allows you to specify that the start of the dash pattern occurs at a given distance after the start of the line. See Section 5.13, “Dash patterns”.
disableddash The dash, fill, stipple, and width values to be used when the item is in the tk.DISABLED state.
fill The color to use in drawing the line. Default is fill='black'.
joinstyle For lines that are made up of more than one line segment, this option controls the appearance of the junction between segments. For more details, see Section 5.12, “Cap and join styles”. The default style is ROUND
offset For stippled lines, the purpose of this option is to match the item's stippling pattern with those of adjacent objects. See Section 5.14, “Matching stipple patterns”..
smooth If true, the line is drawn as a series of parabolic splines fitting the point set. Default is false, which renders the line as a set of straight segments.
splinesteps If the smooth option is true, each spline is rendered as a number of straight line segments. The splinesteps option specifies the number of segments used to approximate each section of the line; the default is splinesteps=12.
state Normally, line items are created in state tk.NORMAL. Set this option to tk.HIDDEN to make the line invisible; set it to tk.DISABLED to make it unresponsive to the mouse.
stipple To draw a stippled line, set this option to a bitmap that specifies the stippling pattern, such as stipple='gray25'. See Section 5.7, “Bitmaps” for the possible values.
tags If a single string, the line is tagged with that string. Use a tuple of strings to tag the line with multiple tags. See Section 8.4, “Canvas tags”.
width The line's width. Default is 1 pixel. See Section 5.1, “Dimensions” for possible values.