I wanna embed a Matplotlib plot directly into a window, QMainWindow.
It should be part of my program with a more complex GUI. ;)
The only way I found was to add the figure as widget into a QTabWidget.
See sample code below.
I lost the link to the webpage what inspired me.
Is there any way to embed the figure directly into the windows like other elements (buttons, textfield, textarea, ...)?
import sys
from PyQt4.QtGui import QApplication, QMainWindow, QDockWidget, QVBoxLayout,QTabWidget, QWidget
from matplotlib import pyplot
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg
a = QApplication(sys.argv)
w = QMainWindow()
t = QTabWidget(w)
Tab1 = QWidget()
t.addTab(Tab1, '1st Plot')
t.resize(1280, 300)
x = [1, 2, 3]
Fig1 = pyplot.Figure();
Plot = Fig1.add_subplot(111);
Plot.plot(x)
Plot.grid();
layout = QVBoxLayout();
layout.addWidget(FigureCanvasQTAgg(Fig1));
Tab1.setLayout(layout);
w.showMaximized()
sys.exit(a.exec_())
Thank you very much.
FigureCanvasQtAgg is just a QWidget like any of the other controls you mentioned. The main difference being it doesn't allow you to pass a parent in the constructor like when you write
t = QTabWidget(w)
You can achieve the same with FigureCanvasQtAgg by calling setParent
canvas = FigureCanvasQtAgg(Fig1)
canvas.setParent(w)
You can also use QMainWindow's setCentralWidget method to add the matplotlib FigureCanvas directly to your main window. However, if you want a more complex gui with other controls I don't see any real problems with your current approach.
Lastly, you shouldn't really be using pyplot when embedding matplotlib. Stick with the object oriented API. Take a look at this example.
This is what I use for PySide. FigureCanvasQTAgg is a qt widget, so you don't need the PlotWidget class. I just find it useful, because it creates the figure for me. It also makes it useful for other projects, because you don't have to deal with importing the right matplotlib objects. From the PlotWidget just call the axes for all of your plotting needs.
from PySide import QtGui
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 NavigationToolbar2QT as NavigationToolbar
class PlotWidget(FigureCanvas):
'''Plotting widget that can be embedded in a PySide GUI.'''
def __init__(self, figure=None):
if figure is None:
figure = Figure(tight_layout=True)
super().__init__(figure)
self.axes = self.figure.add_subplot(111)
self.setSizePolicy(QtGui.QSizePolicy.Expanding, QtGui.QSizePolicy.Expanding)
# end class
if __name__ == "__main__":
import sys
a = QtGui.QApplication(sys.argv)
w = QtGui.QMainWindow()
w.show()
p = PlotWidget()
p.axes.plot([])
nav = NavigationToolbar(p, w)
w.addToolBar(nav)
w.setCentralWidget(p)
# or
# container = QtGui.QWidget()
# layout = QtGui.QHBoxLayout()
# container.setLayout(layout)
# w.setCentralWidget(container)
# layout.addWidget(p)
sys.exit(a.exec_())
Related
I am developing a Desktop application using Qt Designer and PyQt4. I need to display a some figure with contour which in python could be done with matplotlib.pyplot.contourf. I want to display the result inside a QGraphicView object.
I am trying to do it by promoting the QGraphicView to a pygtgraph in Qt-Designer. If object name of QGraphicView is CNOPlot I have written
import matplotlib.pyplot as plt
self.CNOPlot.plot(plt.contourf(xx, yy, Z,cmap=plt.cm.autumn, alpha=0.8))
It is giving output in separate window.
I want this is to be ploted inside CNOPlot.
Here is a short example:
import matplotlib.pyplot as plt
from PyQt4 import QtGui
from PyQt4.Qt import Qt
from matplotlib.figure import Figure
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
class MyView(QtGui.QGraphicsView):
def __init__(self):
QtGui.QGraphicsView.__init__(self)
scene = QtGui.QGraphicsScene(self)
self.scene = scene
figure = Figure()
axes = figure.gca()
axes.set_title("title")
axes.plot(plt.contourf(xx, yy, Z,cmap=plt.cm.autumn, alpha=0.8))
canvas = FigureCanvas(figure)
canvas.setGeometry(0, 0, 500, 500)
scene.addWidget(canvas)
self.setScene(scene)
I'm trying to capture and save to a file whole QWidget window with several matplotlib plots.
I'm adding matplotlib axes to the widget as below:
import sys
from PyQt4 import QtGui
from matplotlib import pyplot as plt
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
app = QtGui.QApplication(sys.argv)
win = QtGui.QWidget()
grid = QtGui.QGridLayout()
fig = plt.figure()
axs = fig.add_subplot(111)
axs.plot([1,2,3,4],[5,6,7,8])
canv = FigureCanvas(fig)
canv.setMaximumHeight(100)
grid.addWidget(canv, 0, 0)
grid.addWidget(QtGui.QLabel('Label'),1,0)
win.setLayout(grid)
win.show()
win.setFixedSize(150,100)
Output window looks ok (output.png - from external print-screen app).
But when I try to capture the output window to the QPixmap object by:
sshot = QtGui.QPixmap.grabWidget(ow)
sshot.save('tmp.png')
tmp.jpg doesn't contain matplotlib figure (tmp.png).
Even when I try to capture whole desktop:
sshot = QtGui.QPixmap.grabWindow(app.desktop().winId())
sshot.save('desktop.png')
the matplotlib figure is empty (desktop.png).
Three screen-shots
How can I capture the whole window without blank matplotlib figures?
Cheers,
Pawel
How can I update a matplotlib plot event driven?
Background:
I wanna program a tool that displays me measured values I receive via a serial port.
These values will be send by a serial connected device when it has measured values and not when the host requests.
Current State:
It seems there is no way to update a plot manually.
When I call the plot()-function more than one time the new plots will be added. Similar to MATLAB or Octave, when you use the "hold on"-Option.
This ends after about 10 calls. Then it is freezed.
When I clear the figures before update, the whole plot disappears.
At least, when the plot is embedded in a window.
Neither draw() nor show() provide a remedy.
When I use a single plot figure, there is no easy way to update, because after the call of show(), the program flow sticks at this line, until the Window is closed. So the update has to be done in a separate thread.
Both problems will be solved, when I use an animation:
import sys
from PyQt4.QtGui import QApplication, QMainWindow, QDockWidget, QVBoxLayout,QTabWidget, QWidget
from PyQt4.QtCore import Qt
from matplotlib import pyplot, animation
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg
from random import randint
a = QApplication(sys.argv)
w = QMainWindow()
t = QTabWidget(w)
Tab1 = QWidget()
t.addTab(Tab1, '1st Plot')
t.resize(1280, 300)
x = [1, 2, 3]
Fig1 = pyplot.Figure();
Plot = Fig1.add_subplot(111);
Plot.plot(x)
Plot.grid();
layout = QVBoxLayout();
layout.addWidget(FigureCanvasQTAgg(Fig1));
Tab1.setLayout(layout);
def UpdateFunction(i):
x.append(randint(0, 10));
Plot.clear();
Plot.plot(x);
Plot.grid();
Anim = animation.FuncAnimation(Fig1, UpdateFunction, interval=500)
w.showMaximized()
sys.exit(a.exec_())
But such an animation is time triggered.
Is there any solution to update event triggered?
The event should be a finished UART read in.
Thank you very much.
Fabian
#tcaswell
Thank you!
This is my actual code:
import sys
from PyQt4.QtGui import QApplication, QMainWindow, QVBoxLayout,QTabWidget, QWidget
from PyQt4.QtCore import SIGNAL
from matplotlib import pyplot
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg
from random import randint
import time
from threading import Thread
a = QApplication(sys.argv)
w = QMainWindow()
t = QTabWidget(w)
Tab1 = QWidget()
t.addTab(Tab1, '1st Plot')
t.resize(1280, 300)
x = [];
x.append(randint(0, 10));
x.append(randint(0, 10));
x.append(randint(0, 10));
Fig1 = pyplot.Figure();
Plot = Fig1.add_subplot(111);
Line, = Plot.plot(x)
Plot.grid();
layout = QVBoxLayout();
layout.addWidget(FigureCanvasQTAgg(Fig1));
Tab1.setLayout(layout);
def triggerUpdate():
while True:
a.emit(SIGNAL('updatePlot()'));
time.sleep(2);
print('update triggered!\n')
def updateFunction():
x.append(randint(0, 10));
#Plot.clear();
Line.set_data(range(len(x)), x);
Fig1.canvas.draw_idle();
print('update done!\n')
a.connect(a, SIGNAL('updatePlot()'), updateFunction)
t = Thread(target=triggerUpdate);
t.start();
w.showMaximized()
sys.exit(a.exec_())
It seems to run, but the content of the plot gets not updated.
The Plot has no canvas. (Although it should have one, otherwise I don't now on what it is plotting when I command it.)
To be honest, I did not understand already the concept of the GUI and plot foo. The missing canvas is covered by its parenting figure. I really don't got it. When there is a figure, what can handle more than one plots, should't each plot have its own canvas?
But I think, here is the problem.
Thank you very much.
I am working with the matplotlib library and PyQt5 with Python 3.6. I add a figure in a window I create, and I wish to set transparent the background of this figure because I add an image to the background of the window. But, the figure is not really transparent, it duplicates the background image of the window.
For example, someone deals with the same problem two years ago :
matplotlib and pyqt4 transparent background
Here is a working example (with a background which is black but the figure is not black) :
import sys, os
from PyQt5.QtCore import Qt
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
import matplotlib
matplotlib.use('Qt5Agg') # Make sure that we are using QT5
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt5agg import NavigationToolbar2QT as NavigationToolbar
from matplotlib.figure import Figure
import matplotlib.pyplot as plt
class SecondWindow(QWidget):
def __init__(self, parent=None):
super(SecondWindow, self).__init__(parent)
self.setupUi(self)
def setupUi(self, Form):
# WINDOW SETTINGS
Form.setWindowTitle('Hello')
self.p = QPalette()
self.pixmap = QPixmap(os.getcwd() + "/logo.png").scaled(self.size(), Qt.IgnoreAspectRatio, Qt.SmoothTransformation)
self.p.setBrush(QPalette.Background, QBrush(self.pixmap))
self.setPalette(self.p)
# CREATE FIGURE AND SETTINGS
self.figure = plt.figure()
self.figure.patch.set_facecolor('None')
self.figure.patch.set_alpha(0)
self.canvas = FigureCanvas(self.figure)
self.axes = self.figure.add_subplot(111)
# WINDOW LAYOUT (with H1 and H2)
self.setLayout(QVBoxLayout())
self.layout().addWidget(self.canvas,1)
self.layout().setContentsMargins(50, 50, 50, 50)
if __name__ == '__main__':
app = QApplication(sys.argv)
form = SecondWindow()
form.show()
sys.exit(app.exec_())
I search for answer during long hours but didn't find a solution yet. Thanks for any help you can bring !
Operating System: Windows 7 Pro
Matplotlib Version: 2.0.2 (installed via Anaconda, conda install matplotlib --channel conda-forge)
Python Version: Python 3.6
Anaconda 3
The problem occurs because the background image is set as a palette to the widget. This causes the canvas to inherit the palette and hence the canvas will also have the image as background, somehow overlaying the widget's background.
A solution would be to set the background of the canvas transparent. An easy way to do so are style sheets.
self.canvas.setStyleSheet("background-color:transparent;")
Note that this is not the same as setting the patches' facecolor to none. The figure has a background, which is controlled inside matplotlib, but the canvas, being a PyQt object also has a background.
Complete example:
import sys, os
from PyQt4.QtCore import Qt
from PyQt4.QtGui import *
import matplotlib
matplotlib.use('Qt4Agg')
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QT as NavigationToolbar
from matplotlib.figure import Figure
import matplotlib.pyplot as plt
plt.rcParams['xtick.color'] ="w"
plt.rcParams['ytick.color'] ="w"
plt.rcParams['font.size'] = 14
class SecondWindow(QWidget):
def __init__(self, parent=None):
super(SecondWindow, self).__init__(parent)
# CREATE FIGURE AND SETTINGS
self.figure = plt.figure()
self.figure.patch.set_facecolor("None")
self.canvas = FigureCanvas(self.figure)
self.axes = self.figure.add_subplot(111)
self.axes.patch.set_alpha(0.5)
###### Make the background of the canvas transparent
self.canvas.setStyleSheet("background-color:transparent;")
self.p = QPalette()
self.p.setBrush(QPalette.Background, QBrush(QPixmap("house.png")))
self.setPalette(self.p)
self.setLayout(QVBoxLayout())
self.layout().addWidget(self.canvas,1)
self.layout().setContentsMargins(50, 50, 50, 50)
if __name__ == '__main__':
app = QApplication(sys.argv)
form = SecondWindow()
form.show()
sys.exit(app.exec_())
which might then look like
I'm working on a QT4 Traits-GUI in Python using Matplotlib for image display, and so far I have this editor modified in an attempt to include a toolbar.
from traitsui.qt4.editor import Editor
from pyface.qt import QtGui, QtCore
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QTAgg as NavigationToolbar
class _MPLFigureEditor(Editor):
"""
Building custom figure editor for displaying matplotlib figures with a qt4-based Traits interface
"""
scrollable = True
def init(self, parent):
self.control = self._create_canvas(parent)
self.set_tooltip()
def update_editor(self):
pass
def _create_canvas(self, parent):
mpl_canvas = FigureCanvas(self.value) #self.value is the figure linked to the editor factory
mpl_toolbar = NavigationToolbar(mpl_canvas,???)
layout = QtGui.QVBoxLayout()
layout.addWidget(mpl_toolbar)
layout.addWidget(mpl_canvas)
return layout
Is this the correct place to create the toolbar? What would be second argument to NavigationToolbar in this case? I'm trying to follow the examples I've found on adding toolbars as QWidgets to figures, but these all create a main_frame within a QMainWindow-based class, not a Traits Editor. Thanks in advance.
Found the answer. Since parent is a QGridLayout itself, we can add the toolbar widget directly to the layout in row 2, column 1 (to place it below the canvas, which I believe is added as a widget in the view-editor creation).
from traitsui.qt4.editor import Editor
from pyface.qt import QtGui, QtCore
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QTAgg as NavigationToolbar
class _MPLFigureEditor(Editor):
"""
Building custom figure editor for displaying matplotlib figures with a qt4-based Traits interface
"""
scrollable = True
def init(self, parent):
self.control = self._create_canvas(parent)
mpl_toolbar = NavigationToolbar(self.control,None)
parent.addWidget(mpl_toolbar,2,1)
self.set_tooltip()
return
def update_editor(self):
pass
def _create_canvas(self, parent):
""" Create the MPL canvas. """
mpl_canvas = FigureCanvas(self.value)
return mpl_canvas
Image zoom/pan does seem to run a bit slow, but that could be another issue altogether.