18 Annotation
Description: Annotation
Keywords: pychart

#
18 Annotation

class `text_box.T`
  A text box is an optional element that adds a text box and arrows to a chart. This class supports the following attributes:

`bottom_fudge`
  Type: length in points (
  xrefunit) Default: 5.

  The amount of space below the last line

`fill_style`
  Type: fill_style.T ( see Section 16) Default: fill_style.white.

  Specifies the fill style of the text box.

`left_fudge`
  Type: length in points (
  xrefunit) Default: 5.

  The amount of space left of the box

`line_style`
  Type: line_style.T ( see Section 14) Default: line_style.black.

  The line style of the surrounding frame.

`loc`
  Type: tuple Default: (0, 0).

  The location of the text box.

`radius`
  Type: length in points (
  xrefunit) Default: 0.

  Radius of the four corners of the rectangle. If the value is zero, a sharp-cornered rectangle is drawn.

`right_fudge`
  Type: length in points (
  xrefunit) Default: 5.

  The amount of space right of the box

`shadow`
  Type: (xoff,yoff,fill) Default: None.

  The value is either None or a tuple. When non-None, a drop-shadow is drawn beneath the object. X-off, and y-off specifies the offset of the shadow relative to the object, and fill specifies the style of the shadow ( see Section 16).

`text`
  Type: str Default: "???".

  Text body. See Section 17

`top_fudge`
  Type: length in points (
  xrefunit) Default: 0.

  The amount of space (in points) above the first line

In addition to the above attributes, this class provides the following methods.

`add_arrow`( | tip, tail=None, arrow=arrow.default)

  This method adds a straight arrow that points to tip, which is a tuple of integers. Parameter tail specifies the starting point of the arrow. It is either None or a string consisting of the following letters:

  > 'l', 'c', 'r', 't', 'm,', 'b'

  Letters 'l', 'c', or 'r' means to start the arrow from the left, center, or right of the text box, respectively. Letters 't', 'm', or 'b' means to start the arrow from the top, middle or bottom of the text box. For example, when `tail = 'tc'` then arrow is drawn from top-center point of the text box. Parameter arrow specifies the style of the arrow.

  See Also:

  Section 19 for arrows.

Annotations example

Below is the source code that produces the above chart. /home/ysaito/pychart/demos/annotations.py

    from pychart import *

    tb = text_box.T(loc=(100,100), text="Without frame")
    tb.add_arrow((50, 100))
    tb.add_arrow((180, 100))
    tb.draw()

    tb = text_box.T(loc=(100,130), text="/hCMulti\n/bLine")
    tb.add_arrow((50, 120))
    tb.add_arrow((180, 100))
    tb.draw()

    tb = text_box.T(loc=(100,160), text="Fat arrow", line_style=None)
    tb.add_arrow((180, 140), tail='rm', arrow = arrow.fat1)
    tb.draw()

    text_box.T(loc=(180, 100), text="/a90Funny background",
               fill_style = fill_style.gray70).draw()

    text_box.T(loc=(180, 140), text="/hL/20Big/oText\n/24/bHuge/oText",
               fill_style = None).draw()