pyqtgraph/examples/text.py

62 lines
1.9 KiB
Python
Raw Normal View History

2012-03-17 15:47:20 +00:00
# -*- coding: utf-8 -*-
2013-02-25 04:09:03 +00:00
"""
This example shows how to insert text into a scene using TextItem. This class
is for displaying text that is anchored to a particular location in the data
coordinate system, but which is always displayed unscaled.
2012-03-17 15:47:20 +00:00
2013-02-25 04:09:03 +00:00
For text that scales with the data, use QTextItem.
For text that can be placed in a layout, use LabelItem.
"""
2012-03-17 15:47:20 +00:00
import initExample ## Add path to library (just for examples; you do not need this)
import pyqtgraph as pg
from pyqtgraph.Qt import QtCore, QtGui
import numpy as np
2012-03-18 03:10:00 +00:00
x = np.linspace(-20, 20, 1000)
2012-03-17 15:47:20 +00:00
y = np.sin(x) / x
2012-03-18 03:10:00 +00:00
plot = pg.plot() ## create an empty plot widget
plot.setYRange(-1, 2)
2013-02-25 04:09:03 +00:00
plot.setWindowTitle('pyqtgraph example: text')
2012-03-18 03:10:00 +00:00
curve = plot.plot(x,y) ## add a single curve
2012-03-17 15:47:20 +00:00
2012-03-18 03:10:00 +00:00
## Create text object, use HTML tags to specify color/size
2016-02-21 08:17:17 +00:00
text = pg.TextItem(html='<div style="text-align: center"><span style="color: #FFF;">This is the</span><br><span style="color: #FF0; font-size: 16pt;">PEAK</span></div>', anchor=(-0.3,0.5), angle=45, border='w', fill=(0, 0, 255, 100))
2012-03-17 15:47:20 +00:00
plot.addItem(text)
text.setPos(0, y.max())
2012-03-18 03:10:00 +00:00
## Draw an arrowhead next to the text box
arrow = pg.ArrowItem(pos=(0, y.max()), angle=-45)
plot.addItem(arrow)
## Set up an animated arrow and text that track the curve
curvePoint = pg.CurvePoint(curve)
plot.addItem(curvePoint)
text2 = pg.TextItem("test", anchor=(0.5, -1.0))
text2.setParentItem(curvePoint)
arrow2 = pg.ArrowItem(angle=90)
arrow2.setParentItem(curvePoint)
## update position every 10ms
index = 0
def update():
global curvePoint, index
index = (index + 1) % len(x)
curvePoint.setPos(float(index)/(len(x)-1))
text2.setText('[%0.1f, %0.1f]' % (x[index], y[index]))
timer = QtCore.QTimer()
timer.timeout.connect(update)
timer.start(10)
2012-03-17 15:47:20 +00:00
## Start Qt event loop unless running in interactive mode or using pyside.
if __name__ == '__main__':
import sys
if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
QtGui.QApplication.instance().exec_()