I am using pyqtgraph to visualate 2D arrays. Due to the fact that I have to refresh the visualated Image because of a real time application which I want to evaluate I am using GraphicsView(). Then I create a ImageItem and I want to add the Item to the created window. Unfortunately the image is only visible in the left upper corner of the window. I know that I can show the full image without GraphicsView but as I said I will need GraphicsView later to visualate the updated values in real time for an application.
Here is my current code:
import numpy as np
from pyqtgraph.Qt import QtGui, QtCore
import pyqtgraph as pg
import struct
import sounddevice as sd
from scipy.fftpack import fft
import sys
import time
class Fenster(pg.GraphicsLayoutWidget): #objektorientiert arbeiten!!
def __init__(self): #constructor
super().__init__() #ruft den constructor von QWidget auf
self.initMe()
class Fenster(pg.GraphicsLayoutWidget):
def __init__(self):
super().__init__()
self.initMe()
def initMe(self):
self.win = pg.GraphicsView()
self.win.show()
self.plot_data = np.fromfunction(lambda i, j: (1+0.3*np.sin(i)) * (i)**2 + (j)**2, (100, 100))
self.img = pg.ImageItem(image=self.plot_data)
self.cm = pg.colormap.get('CET-L9')
self.bar = pg.ColorBarItem( values= (0, 20_000), colorMap=self.cm )
self.bar.setImageItem(self.img)
self.win.setCentralItem(self.img)
w = Fenster()
That is the output image:
How can I set that the image fullfill the whole window?
How can I do that the created ColorBarItem will be showed in the window? (optionally)
Thanks in advance.
I found the solution. You have to create a PlotItem. Then add the ImageItem to the PlotItem and set the PlotItem in the center of GraphicsView
self.win = pg.GraphicsView()
self.win.show()
self.p = pg.PlotItem()
self.win.setCentralItem(self.p)
self.plot_data = np.fromfunction(lambda i, j: (1+0.3*np.sin(i)) * (i)**2 + (j)**2, (100, 100))
self.img = pg.ImageItem(image=self.plot_data)
self.cm = pg.colormap.get('CET-L9')
self.bar = pg.ColorBarItem( values= (0, 20_000), colorMap=self.cm )
self.bar.setImageItem(self.img)
self.p.addItem(self.img)
I also figured out to update the plot (live plot). Leave a comment if I should share.
Related
I'm trying to center a QLabel showing a pixmap inside a QWidget both horizontally and vertically, but for some reason, this seems impossible. I have read many similar questions, and it seems they all comes down to specifying the alignment when adding the label to the layout. Well, I'm doing that and still it's aligning to the top left corner. Can someone please help me center my darn QLabel already? :)
main.py
import sys
from PyQt5.QtWidgets import QApplication
from mainwindow import MainWindow
app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec()
mainwindow.py
from PyQt5.QtGui import QGuiApplication, QWheelEvent
from PyQt5.QtWidgets import QMainWindow
from imagewidget import ImageWidget
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.resize(QGuiApplication.primaryScreen().availableSize() * 3 / 5)
self.image_widget = ImageWidget()
self.setCentralWidget(self.image_widget)
def wheelEvent(self, event: QWheelEvent) -> None:
angleDelta = event.angleDelta().y()
if angleDelta >= 0:
self.image_widget.zoomIn()
else:
self.image_widget.zoomOut()
imagewidget.py
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QPixmap, QPalette
from PyQt5.QtWidgets import QWidget, QVBoxLayout, QLabel, QSizePolicy, QPushButton
class ImageWidget(QWidget):
def __init__(self):
super().__init__()
self.scale_factor = 1.0
self.label = QLabel()
self.label.setAlignment(Qt.AlignVCenter)
self.label.setPixmap(QPixmap("image.png")) # Loads local test image
self.label.setSizePolicy(QSizePolicy.Ignored, QSizePolicy.Ignored)
self.label.setScaledContents(True)
self.layout = QVBoxLayout()
self.layout.addWidget(self.label, Qt.AlignCenter) # Why does this not align the label to the center of the layout?
self.setLayout(self.layout)
def zoomIn(self):
self.scale_factor *= 1.1
self.resizeUsingScaleFactor()
def zoomOut(self):
self.scale_factor /= 1.1
self.resizeUsingScaleFactor()
def getImageSize(self):
return self.label.pixmap().size()
def resizeUsingScaleFactor(self):
self.label.resize(self.getImageSize() * self.scale_factor)
When you resize a widget it doesn't adjust its position, it just resize it. All widgets set their geometry based on the origin point (the top left corner), if you use resize the origin point will always remain the same.
Since you are using a layout, you should leave the positioning to the layout (which you are also preventing since you're using the Ignore size policy, which is a problem in these cases. Also note that you are using the alignment as the second argument for addWidget, but its signature is addWidget(widget, stretch=0, alignment=Qt.Alignment()), so you should use the correct keyword.
The solution is to use setFixedSize instead, which will ensure that the layout takes care of the correct alignment once it has been notified about the new fixed size (which does not happen when you use resize).
class ImageWidget(QWidget):
def __init__(self):
super().__init__()
self.scale_factor = 1.0
self.label = QLabel()
# no need for this
# self.label.setAlignment(Qt.AlignCenter)
# don't do this
# self.label.setSizePolicy(QSizePolicy.Ignored, QSizePolicy.Ignored)
self.label.setPixmap(QPixmap("image.png")) # Loads local test image
self.label.setScaledContents(True)
self.layout = QVBoxLayout()
self.layout.addWidget(self.label, alignment=Qt.AlignCenter)
self.setLayout(self.layout)
# ...
def resizeUsingScaleFactor(self):
self.label.setFixedSize(self.getImageSize() * self.scale_factor)
I am just trying to write a GUI to help me while measuring. For now, I want to be able to plot -Voltages for example- in real-time from my Arduino UNO. Sadly this code just works fine for around 5 seconds, after this the tkinter windows freezes. Amazingly the v and t list works. Would you please give me a hint to fix this problem? I just spend hours.
from pyfirmata import Arduino, util
import matplotlib
matplotlib.use('TkAgg')
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
from matplotlib.figure import Figure
from tkinter import *
import time
import threading
board=Arduino('COM3')
iterator = util.Iterator(board)
iterator.start()
Tvl = board.get_pin('a:0:i')
class mclass(threading.Thread):
def __init__(self, window):
threading.Thread.__init__(self)
self.window = window
self.box = Entry(window)
self.button = Button (window, text="check", command=self.plot)
self.box.pack ()
self.button.pack()
self.t=[]
self.v=[]
self.fig = Figure(figsize=(6,6))
self.a = self.fig.add_subplot(111)
self.a.invert_yaxis()
self.a.set_title ("Estimation Grid", fontsize=16)
self.a.set_ylabel("Y", fontsize=14)
self.a.set_xlabel("X", fontsize=14)
self.canvas = FigureCanvasTkAgg(self.fig, master=self.window)
self.canvas.get_tk_widget().pack(side=BOTTOM, fill=BOTH, expand=False)
def plot (self):
global t,v
clock=time.perf_counter()
while time.perf_counter()-clock<=float(self.box.get()):
self.v.append(Tvl.read())
self.t.append(time.perf_counter()-clock)
if len(self.v)>=25:
del self.v[0]
del self.t[0]
self.a.clear()
self.a.plot(self.t,self.v)
self.canvas.draw()
window= Tk()
t= mclass(window)
t.start()
window.mainloop()
I thank you for your comments. In the end patthoyts hint worked quite well. I would be verry interested why while loops in this case dont work.
Beneath ist the new stable Code with some more Features added.
thanks and greets peterudo
from pyfirmata import Arduino, util
import matplotlib
matplotlib.use('TkAgg')
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
from matplotlib.figure import Figure
from tkinter import *
import time
import threading
board=Arduino('COM3')
iterator = util.Iterator(board)
iterator.start()
Tvl = board.get_pin('a:0:i')
class mclass(threading.Thread):
def __init__(self, window):
threading.Thread.__init__(self)
self.window = window
self.box = Entry(window)
self.box.pack ()
self.button = Button (window, text="check", command=self.plot)
self.button.pack()
self.button2 = Button(window,text="stop", command=self.start_stop)
self.button2.pack()
self.w=Scale(window, from_=0, to=10000)
self.w.pack()
self.w2=Scale(window, from_=0, to=100000)
self.w2.pack()
self.t=[]
self.v=[]
self.ss=True
self.fig = Figure(figsize=(6,6))
self.a = self.fig.add_subplot(111)
self.a.invert_yaxis()
self.a.set_title ("Estimation Grid", fontsize=16)
self.a.set_ylabel("Y", fontsize=14)
self.a.set_xlabel("X", fontsize=14)
self.canvas = FigureCanvasTkAgg(self.fig, master=self.window)
self.canvas.get_tk_widget().pack(side=BOTTOM, fill=BOTH, expand=False)
def plot (self):
window.after(10, self.plot)
if self.ss==True:
self.v.append(Tvl.read())
self.t.append(time.perf_counter())
if self.t[0]<self.t[len(self.t)-1]-0.0001*self.w2.get():
del self.v[0]
del self.t[0]
self.a.clear()
self.a.set_ylim(Tvl.read()-0.0001*self.w.get(),Tvl.read()+0.0001*self.w.get())
self.a.set_xlim(self.t[len(self.t)-1]-0.001*self.w2.get()+1,time.perf_counter())
self.a.plot(self.t,self.v)
self.canvas.draw()
def start_stop(self):
if self.ss==True:
self.ss=False
else:
self.ss=True
window= Tk()
t= mclass(window)
t.start()
window.mainloop()
I am trying to develop a python app for a RaspberryPi on a PC. In order to test one aspect, I have written an object class to emulate an OLED display device (hardware) that the PC cannot use (no I2C). The Wdisp class is simply loaded in place of the hardware driver when using the PC.
I have another class that wraps up the few OLED functions I need ( write text , draw progressbar etc. )
# OLED display object
import os
Win = False
if os.name == 'nt':
Win=True
from WindowsOLED import Wdisp
else:
import Adafruit_GPIO.SPI as SPI
import Adafruit_SSD1306
from PIL import Image
from PIL import ImageDraw
from PIL import ImageFont
class OLEDDisplay(object):
def __init__(self):
# Raspberry Pi pin configuration:
RST = 24
if Win:
self.disp = Wdisp()
else:
self.disp = Adafruit_SSD1306.SSD1306_128_64(rst=RST)
# Initialize library.
self.disp.begin()
# Create blank image for drawing.
self.width = 128 #self.disp.width
self.height = 64 #self.disp.height
self._image = Image.new('1', (self.width, self.height))
self.draw = ImageDraw.Draw(self._image)
# Load default font.
self.font = ImageFont.load_default()
self.clear()
def __del__(self):
self.clear()
def __repr__(self):
return 'OLED display object for SSD1306 I2C'
def clear(self):
# Clear display
self.disp.clear()
self.disp.display()
def write(self, text):
self.draw.text((0, 2), text, font=self.font, fill=255)
self._show()
def progressbar(self, percent):
#draw a progress bar on top half of screen
shape_width = self.width * (percent/100)
padding =2
top = padding
bottom = (self.height/2) - padding
x = padding
self.draw.rectangle((x, top, self.width-padding, bottom), outline=255, fill=0)
self.draw.rectangle((x, top, x+shape_width, bottom), outline=255, fill=255)
self._show()
def loadimage(self, imagefile):
#open, convert and display an image
self._image = Image.open(imagefile).resize((self.disp.width,
self.disp.height),
Image.ANTIALIAS).convert('1')
self._show()
def _show(self):
# Display image.
self.disp.image(self._image)
self.disp.display()
If I test this class at the command line
Example:
>>> from OLEDDisplay import*
>>> OD = OLEDDisplay()
>>> OD.progressbar(50)
Its works fine - the OLEDDisplay object draws on a PIL image object, passes the image to the Wdisp object and the Wdisp object converts the image to a BitMapImage and displays in on a Tkinter Label ( self.L ).
#Windows subsitute OLED display class
#displays a label image for testing
from tkinter import *
from PIL import Image, ImageTk
from tkinter import filedialog, messagebox
from tkinter.constants import *
class Wdisp(object):
i=None
width = 128
height =64
_image = None
def __init__(self):
self.master = Tk()
self._image = Image.new('1', (self.width, self.height))
self.i = ImageTk.PhotoImage(self._image)
self.L= Label(self.master, text="label place holder", image=self.i)
self.L.pack(expand=YES, fill=BOTH)
def begin(self):
pass
def image(self, newimage):
self._image = newimage
def display(self):
#display the image
self.i = ImageTk.BitmapImage(self._image)
self.L.config(image=self.i)
However, if I use this in my app or test it in a small app:
from tkinter import *
from PIL import Image, ImageTk
from tkinter import filedialog, messagebox
from tkinter.constants import *
from OLEDDisplay import*
def updateOLED():
text = E.get
print(text)
OD.write(text)
master = Tk()
OD = OLEDDisplay()
E = Entry(master)
B = Button(master, text="update OLED", command = updateOLED)
E.pack()
B.pack()
It fails with a tkinter.TclError: image "pyimage4" doesn't exist:
Traceback (most recent call last):
File "D:\My Documents\PI Projects\Pyprojects\PTPIC\OLEDDisplay test.py", line 19, in <module>
OD = OLEDDisplay()
File "D:\My Documents\PI Projects\Pyprojects\PTPIC\OLEDDisplay.py", line 42, in __init__
self.clear()
File "D:\My Documents\PI Projects\Pyprojects\PTPIC\OLEDDisplay.py", line 52, in clear
self.disp.clear()
File "D:\My Documents\PI Projects\Pyprojects\PTPIC\WindowsOLED.py", line 45, in clear
self.display()
File "D:\My Documents\PI Projects\Pyprojects\PTPIC\WindowsOLED.py", line 36, in display
self.L.config(image=self.i)
File "C:\Python34\lib\tkinter\__init__.py", line 1324, in configure
return self._configure('configure', cnf, kw)
File "C:\Python34\lib\tkinter\__init__.py", line 1315, in _configure
self.tk.call(_flatten((self._w, cmd)) + self._options(cnf))
_tkinter.TclError: image "pyimage4" doesn't exist
I have no idea why : perhaps variable scope? perhaps something weird with PIL , so any suggestions welcome.
Cheers Bill
I'm working on a GUI that basically hold multiple widgets that each contain a figure as well as a few buttons/whatever. One of the figures is supposed to be interactive, calling a function whenever the user clicks on any part of the plot. Yet I can't get the function to fire using mpl_connect, even after playing with focus and whatnot. I'm somewhat new to PySide/Qt, so I don't exactly understand why my code is behaving like this (I've been searching for days for a solution, but haven't found anything about it).
I used Qt Designer to create the layout for the GUI. I'm using Spyder from Anaconda 2.2.0 (32-bit), Python 2.7, and PySide to develop the GUI. If it's any help, I come from more of a MATLAB background where I developed a full version of the GUI I'm trying to make in Python.
Below is the relevant code (scroll down a bit to see where the problem is):
from PySide import QtCore, QtGui
from PySide.QtCore import *
from PySide.QtGui import *
import numpy as np
import matplotlib
matplotlib.use('Qt4Agg')
matplotlib.rcParams['backend.qt4']='PySide'
from matplotlib.figure import Figure
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QTAgg as NavigationToolbar
import matplotlib.pyplot as plt
from PySide.QtGui import QPalette, QCursor
import matplotlib.colors as colors
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(1316, 765)
self.centralwidget = QtGui.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.widget = QtGui.QWidget(self.centralwidget)
self.widget.setGeometry(QtCore.QRect(75, 40, 375, 490))
self.widget.setObjectName("widget")
color = self.centralwidget.palette().color(QPalette.Window)
self.leftPlot = MatplotlibWidget(None,'','','',False,color)
self.setupPlot(self.widget,self.leftPlot)
self.leftPlot.figure.tight_layout()
self.leftImage = self.leftPlot.axes.imshow(self.defaultSlide, cmap = mymap)
Snippet of interest:
self.leftPlot.figure.canvas.setFocusPolicy(QtCore.Qt.StrongFocus)
self.leftPlot.figure.canvas.setFocus()
cid = self.leftPlot.figure.canvas.mpl_connect('button_release_event', self.getCoordinates) # doesn't get called
plt.show()
def getCoordinates(self, event):
print 'dasdsadadsa'
print 'button=%d, x=%d, y=%d, xdata=%f, ydata=%f'%(event.button, event.x, event.y, event.xdata, event.ydata)
The rest:
class MatplotlibWidget(FigureCanvas):
def __init__(self, parent=None,xlabel='x',ylabel='y',title='Title',showTicks=False,color=None):
super(MatplotlibWidget, self).__init__(Figure())
self.setParent(parent)
if color != None:
self.figure = Figure(facecolor=(color.red()/256.0,color.green()/256.0,color.blue()/256.0),frameon=0)
else:
self.figure = Figure(frameon=0)
self.canvas = FigureCanvas(self.figure)
self.axes = self.figure.add_subplot(111)
self.axes.set_xlabel(xlabel)
self.axes.set_ylabel(ylabel)
self.axes.set_title(title)
self.axes.get_xaxis().set_visible(showTicks)
self.axes.get_yaxis().set_visible(showTicks)
class ControlMainWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
super(ControlMainWindow, self).__init__(parent)
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
plt.show()
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
mySW = ControlMainWindow()
mySW.show()
sys.exit(app.exec_())
I'm aware the code is messy, but any input is greatly appreciated.
Update (2015-09-04) : I've updated the MWE I provided as part of my original answer to use instead the approach that is suggested in the matplotlib documentation to embed a mpl figure in an application. This approach does not use the pyplot interface (as in my original answer) and use the Object Oriented API of mpl instead. Also, since all the mpl artists (figure, axes, etc.) know each other, there is no need to explicitly create new class variables. This allows a structure of code that is, IMO, easier to read and to maintain.
The problem comes from the fact that you are not connecting correctly your event to self.leftPlot (FigureCanvasQTAgg), but to self.leftPlot.figure.canvas (FigureCanvasQTAgg.figure.FigureCanvasQTAgg) instead. You are creating a canvas within a canvas in the MatplotlibWidget class (which is already a subclass of FigureCanvasQTAgg). You only need to create one mpl canvas, pass a figure to it, and then connect the event to it directly.
I've put together a MWE to demonstrate how this can be done using the Object Oriented API of Matplotlib as suggested in the documentation:
from PySide import QtGui
import numpy as np
import sys
import matplotlib as mpl
mpl.use('Qt4Agg')
mpl.rcParams['backend.qt4']='PySide'
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg
class ControlMainWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
super(ControlMainWindow, self).__init__(parent)
self.setupUi()
def setupUi(self):
figure = mpl.figure.Figure(figsize=(5, 5))
leftPlot = MatplotlibWidget(figure)
self.setCentralWidget(leftPlot)
class MatplotlibWidget(FigureCanvasQTAgg):
def __init__(self, fig):
super(MatplotlibWidget, self).__init__(fig)
#-- set up an axe artist --
ax = fig.add_axes([0.1, 0.1, 0.85, 0.85])
ax.plot(np.arange(15), np.arange(15))
self.draw()
#---- setup event ----
self.mpl_connect('button_press_event', self.onclick)
def onclick(self, event):
x, y = event.x, event.y
print(x, y)
if x != None and y != None:
ax = self.figure.axes[0]
ax.plot(event.xdata, event.ydata, 'ro')
self.draw()
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
mySW = ControlMainWindow()
mySW.show()
sys.exit(app.exec_())
The code above results in:
Here is my code:
from tkinter import *
import textwrap
GUI = Tk()
note_frame = Frame(GUI)
note_frame.grid(row=0, column=0)
note_scrollbar = Scrollbar(note_frame)
note_scrollbar.pack(side=RIGHT, fill=Y)
note_container = Canvas(note_frame, yscrollcommand = note_scrollbar.set)
note_container.pack()
note_scrollbar.config(command=note_container.yview)
def configure_note_container(event):
note_container.config(scrollregion=note_container.bbox("all"),
width=200, height=200)
note_list = Frame(note_container, width=200, height=200)
note_container.create_window((0,0), window=note_list, anchor='nw')
note_list.bind("<Configure>", configure_note_container)
for x in range(100):
exec(textwrap.dedent(
"""
label_{0} = Label(note_list, text='{0}', bg="white")
label_{0}.grid(column=0, row={0})
""".format(x)))
GUI.mainloop()
I am trying to get the labels to stretch out to fill the X width of the grid cell within the frame (which is within a canvas so that I can use a scrollbar), but I don't know how to do it - when the note_container gets configured, it seems to cancel out any adjustment of size. grid_propagate doesn't seem to work either.
Any help is appreciated. thanks.