I have a form created with PyQt5 Designer. Within this form, I have a QPushButton and a QWidget. I want to draw shapes on the QWidget with QPainter. I want to draw on the QWidget (named drawing_area) with custom methods such as my_rectangle(), my_line(), etc. I also want to trigger a custom function clear_drawings() to clean the drawings on the widgets by a button click. Following is my UI. I couldn't figure out how to target a certain QWidget within a form. I appreciate guidance here.
from PyQt5 import QtCore, QtGui, QtWidgets
class Ui_Form(object):
def setupUi(self, Form):
Form.setObjectName("Form")
Form.resize(770, 347)
self.drawButton = QtWidgets.QPushButton(Form)
self.drawButton.setGeometry(QtCore.QRect(20, 60, 91, 24))
self.drawButton.setObjectName("drawButton")
self.drawing_area = QtWidgets.QWidget(Form)
self.drawing_area.setGeometry(QtCore.QRect(280, 30, 381, 191))
self.drawing_area.setAutoFillBackground(False)
self.drawing_area.setObjectName("drawing_area")
self.retranslateUi(Form)
QtCore.QMetaObject.connectSlotsByName(Form)
def retranslateUi(self, Form):
_translate = QtCore.QCoreApplication.translate
Form.setWindowTitle(_translate("Form", "Form"))
self.drawButton.setText(_translate("Form", "Click to Draw!"))
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
Form = QtWidgets.QWidget()
ui = Ui_Form()
ui.setupUi(Form)
Form.show()
sys.exit(app.exec_())
Related
Here is a minimal GTK 4 app written using the Python bindings, based on this tutorial. It displays a window with a very long block of text:
import sys
import gi
gi.require_version('Gtk', '4.0')
gi.require_version('Adw', '1')
from gi.repository import Gtk, Adw
class MainWindow(Gtk.ApplicationWindow):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
long_label = Gtk.Label.new("Here is a very long chunk of text.\n" * 100)
self.set_child(long_label)
class MyApp(Adw.Application):
def __init__(self, **kwargs):
super().__init__(**kwargs)
self.connect('activate', self.on_activate)
def on_activate(self, app):
self.win = MainWindow(application=app)
self.win.present()
if __name__ == "__main__":
app = MyApp(application_id="com.example.GtkApplication")
app.run(sys.argv)
The tutorial uses the class Gtk.ApplicationWindow for the MainWindow, which lets you set the application_id in the main function and other convenient features.
However, the default Gtk.ApplicationWindow does not include a scrollbar. Rather than build one manually, it seems the best way to do this is to make my main window an instance of Gtk.ScrolledWindow, documented here, which lets you specify the scroll behavior etc. at a high level.
Unfortunately, dropping Gtk.ScrolledWindow in place of Gtk.ApplicationWindow causes an error:
TypeError: gobject `__main__+MainWindow' doesn't support property `application'
Is there a way to create a Gtk.ApplicationWindow that is also a Gtk.ScrolledWindow?
If not, what is the best way to get a scrollbar in my main window?'
(I have added the pygobject tag because it is the language of my MWE, but I think that my question is agnostic with respect to the binding language.)
A Gtk.ScrolledWindow isn't really a "window" per se as most people know it (it used to map to the very specific concept of a X11 Window). It's a widget that allows you to scroll through its child widget.
In other words, if you want an application window where you can scroll through the content, you would wrap your Gtk.Label with a Gtk.ScrolledWindow and you would then set that as the Gtk.ApplicationWindow's child.
In other words, your MainWindow would become:
class MainWindow(Gtk.ApplicationWindow):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
long_label = Gtk.Label(label=("Here is a very long chunk of text.\n" * 100))
# Wrap a scrolled window around it
scrolled = Gtk.ScrolledWindow()
scrolled.set_child(long_label)
# Set it as the main child of the window
self.set_child(scrolled)
from kivy.app import App
from kivy.uix.gridlayout import GridLayout
from kivy.uix.label import Label
from kivy.uix.textinput import TextInput
from kivy.uix.button import Button
class LoginScreen(GridLayout):
def __init__(self, **kwargs):
super(LoginScreen, self).__init__(**kwargs)
self.cols = 2
self.submit = Button(text='Order', font_size=40)
self.add_widget(self.submit)
self.submit.bind(on_press=self.pressed)
def pressed(self, instance):
pressing = Secondtab()
pressing()
class Secondtab(GridLayout):
def __init__(self, **kwargs):
super(Secondtab, self).__init__(**kwargs)
self.cols = 5
self.submit = Button(text='Drinks', font_size=40)
self.add_widget(self.submit)
print('check')
def __call__(self):
print('new tab')
class MyApp(App):
def build(self):
return LoginScreen()
if __name__ == '__main__':
MyApp().run()
So I want the window to change to a new layout when I press the first button. I tought making a new grid class and calling it would work but it didnt work as I expected. I dont want the button to open a new window tho I want the current window to refresh to the new layout.
As #John Anderson suggested. Take a look at the screen manager widget. The 'current window' must be a populated screen widget and you could change the current screen by assigning the next screen's name to the current attribute.
This will help you I guess. Using ScreenManager:
from kivy.uix.screenmanager import ScreenManager, Screen, SlideTransition
class LoginScreen(GridLayout):
def __init__(self, **kwargs):
super(LoginScreen, self).__init__(**kwargs)
self.cols = 2
self.submit = Button(text='Order', font_size=40)
self.add_widget(self.submit)
self.submit.bind(on_press=self.pressed)
def pressed(self, instance):
pressing = Secondtab()
pressing()
myapp.screen_manager.transition = SlideTransition(direction='left', duration=.25) #You can change transition speed or you could just remove it to set it on default
myapp.screen_manager.current = 'Secondtab'
class MyApp(App):
def build(self):
return LoginScreen()
self.screen_manager = ScreenManager()
self.loginscreen = LoginScreen()
screen = Screen(name='LoginScreen')
screen.add_widget(self.loginscreen)
self.screen_manager.add_widget(screen)
self.secondtab = Secondtab()
screen = Screen(name='Secondtab')
screen.add_widget(self.secondtab)
self.screen_manager.add_widget(screen)
return self.screen_manager
I am following the example code I've attached below. It currently displays the plot and associated slider embedded in the doc returned by the "modify_doc" function in the notebook. However, I'd like to deploy it into it's own server to make a GUI, while still maintaining it's ability to run the callback when the slider is changed and update the plot. However when I try to use Panel Pyviz to deploy it, it just displays the message "< bokeh.document.document.Document object at 0x00000193EC5FFE80 >" on the server that pops up. How do I deploy the doc in a way that will display the image?
import numpy as np
import holoviews as hv
from bokeh.io import show, curdoc
from bokeh.layouts import layout
from bokeh.models import Slider, Button
renderer = hv.renderer('bokeh').instance(mode='server')
# Create the holoviews app again
def sine(phase):
xs = np.linspace(0, np.pi*4)
return hv.Curve((xs, np.sin(xs+phase))).opts(width=800)
stream = hv.streams.Stream.define('Phase', phase=0.)()
dmap = hv.DynamicMap(sine, streams=[stream])
# Define valid function for FunctionHandler
# when deploying as script, simply attach to curdoc
def modify_doc(doc):
# Create HoloViews plot and attach the document
hvplot = renderer.get_plot(dmap, doc)
# Create a slider
def slider_update(attrname, old, new):
# Notify the HoloViews stream of the slider update
stream.event(phase=new)
start, end = 0, np.pi*2
slider = Slider(start=start, end=end, value=start, step=0.2, title="Phase")
slider.on_change('value', slider_update)
# Combine the holoviews plot and widgets in a layout
plot = layout([
[hvplot.state],
[slider]], sizing_mode='fixed')
doc.add_root(plot)
return doc
# To display in the notebook
show(modify_doc, notebook_url='localhost:8888')
# To display in a script
doc = modify_doc(curdoc())
# To deploy to separate server using Panel (attempt, doesn't work. Just displays #"<bokeh.document.document.Document object at 0x00000193EC5FFE80>":
graph = pn.Row (doc)
graph.show()
There is some mixing of very different APIs going on in your example. Panel is meant to simplify some of Bokeh's APIs so a lot of what you're doing here isn't necessary. That said I'll provide a few versions which are either using only Panel components or combining Panel and bokeh components.
To start with this is how I might write this example using just Panel:
import numpy as np
import panel as pn
import holoviews as hv
pn.extension()
start, end = 0, np.pi*2
slider = pn.widgets.FloatSlider(start=start, end=end, value=start, step=0.2, name="Phase")
#pn.depends(phase=slider.param.value)
def sine(phase):
xs = np.linspace(0, np.pi*4)
return hv.Curve((xs, np.sin(xs+phase))).opts(width=800)
dmap = hv.DynamicMap(sine)
row = pn.Row(dmap, slider)
# Show in notebook
row.app('localhost:8888')
# Open a server
row.show()
# To deploy this using `panel serve` or `bokeh serve`
row.servable()
In your example you instead use various bokeh components, this is also possible and might be desirable if you've already got bokeh code.
import numpy as np
import holoviews as hv
import panel as pn
from bokeh.models import Slider, Button
# Create the holoviews app again
def sine(phase):
xs = np.linspace(0, np.pi*4)
return hv.Curve((xs, np.sin(xs+phase))).opts(width=800)
stream = hv.streams.Stream.define('Phase', phase=0.)()
dmap = hv.DynamicMap(sine, streams=[stream])
def slider_update(attrname, old, new):
# Notify the HoloViews stream of the slider update
stream.event(phase=new)
start, end = 0, np.pi*2
slider = Slider(start=start, end=end, value=start, step=0.2, title="Phase")
slider.on_change('value', slider_update)
graph = pn.Row(dmap, slider)
# Show in notebook
row.app('localhost:8888')
# Open a server
row.show()
# To deploy this using `panel serve` or `bokeh serve`
row.servable()
If you want to serve these apps to multiple people I'd definitely recommend using panel serve but if you really want to make a script you can run with python script.py you should do this:
def app():
start, end = 0, np.pi*2
slider = pn.widgets.FloatSlider(start=start, end=end, value=start, step=0.2, name="Phase")
#pn.depends(phase=slider.param.value)
def sine(phase):
xs = np.linspace(0, np.pi*4)
return hv.Curve((xs, np.sin(xs+phase))).opts(width=800)
dmap = hv.DynamicMap(sine)
return pn.Row(dmap, slider)
pn.serve({'/': app})
This requires latest Panel, but ensures that even if you run the app as a script that each user gets a new instance of the app which does not share state with all others.
I have a Gio.Icon (or GIcon in C, I'm using pygobject). Right now I'm using the following code to create a Gtk.Image from the Gio.Icon:
image = icon and Gtk.Image(gicon=icon, icon_size=Gtk.IconSize.DIALOG, pixel_size=48, use_fallback=True)
The problem is, that the Gio.Icon isn't garanteed to have a valid icon name/path and when it doesn't it shows a broken image icon. I would like to fall back to using a different icon I know exists if the supplied Gio.Icon is invalid. Is there some way to know if the Gio.Icon is invalid, or if the Gtk.Image would show as a broken image?
EDIT
A minimal example:
import gi
gi.require_version('Gtk', '3.0')
from gi.repository import Gtk, Gio
win = Gtk.Window()
win.connect('destroy', Gtk.main_quit)
icon = Gio.Icon.new_for_string('gnome-garbage')
fallback_icon = Gio.Icon.new_for_string('folder')
image = Gtk.Image(gicon=icon, icon_size=Gtk.IconSize.DIALOG, pixel_size=48)
win.add(image)
win.show_all()
Gtk.main()
I found an answer in the GtkImage documentation:
If the file isn’t loaded successfully, the image will contain a “broken image” icon similar to that used in many web browsers. If you want to handle errors in loading the file yourself, for example by displaying an error message, then load the image with gdk_pixbuf_new_from_file(), then create the GtkImage with gtk_image_new_from_pixbuf().
Although, in my case I actually need to use a GtkIconTheme to get a PixBuf instead of gdk_pixbuf_new_from_file:
import gi
gi.require_version('Gtk', '3.0')
from gi.repository import Gtk, Gio
win = Gtk.Window()
win.connect('destroy', Gtk.main_quit)
def load_icon(icon):
info = Gtk.IconTheme.get_default().lookup_by_gicon(icon, 48, Gtk.IconLookupFlags.FORCE_SIZE)
if info:
return info.load_icon()
icon = Gio.Icon.new_for_string('gnome-garbage')
fallback_icon = Gio.Icon.new_for_string('folder')
pixbuf = load_icon(icon) or load_icon(fallback_icon)
image = Gtk.Image.new_from_pixbuf(pixbuf)
win.add(image)
win.show_all()
Gtk.main()
I have the following peace of code
from ipywidgets import widgets
from IPython.display import display
import numpy as np
class Test(object):
def __init__(self, arraylen):
self.a = np.random.randn(arraylen)
self.button = widgets.Button(description = 'Show')
self.button.on_click(self.show)
display(self.button)
self.button1 = widgets.Button(description = 'Show1')
self.button1.on_click(self.show)
display(self.button1)
def show(self, ev = None):
np.savetxt('test',self.a)
self.button.disabled = True
test = Test(10)
The output is two buttons in a column as shown here:
Would it also be possible, to embed the buttons in a HTML table (where I could choose them to be in a row), or any other organization scheme? Maybe it could look like this:
You could use (a very basic example):
from IPython.display import display
from ipywidgets import widgets
button1 = widgets.Button(description = 'Button1')
button2 = widgets.Button(description = 'Button2')
display(widgets.HBox((button1, button2)))
Here you can find basic and more complete examples about the use of the widgets. If you are using Jupyter you should adapt some info (from ipywidgets import widgets instead from IPython.html import widgets,...).