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How to use MapType in qml?

I am working on a gui project in python, where i want to show a map using pyqt.
I've stumbled upon a way of using qml to do just that, and I was able to show a simple map, but when I try customizing it's appearance using the activeMapType property, the program only show a blank white screen. (I dont have debug messages, cause I'm not using Qt creator)
I suspect a problem is in the declaration of "map_type", but i can't figure what it is.
The python code (simply loads the qml file):
import os
from PyQt5 import QtCore, QtWidgets, QtQuickWidgets, QtPositioning
from PyQt5.QtQuick import QQuickView
from PyQt5.QtWidgets import *
if __name__ == '__main__':
app = QApplication([])
w = QtQuickWidgets.QQuickWidget()
qml_path = os.path.join(os.path.dirname(__file__), "main.qml")
w.setSource(QtCore.QUrl.fromLocalFile(qml_path))
w.setResizeMode(QtQuickWidgets.QQuickWidget.SizeRootObjectToView)
w.show()
app.exec()
Main.qml:
import QtQuick 2.11
import QtPositioning 5.11
import QtLocation 5.11
Rectangle {
id:rectangle
width: 640
height: 480
Plugin {
id: osmPlugin
name: "osm"
}
MapType {
id: map_type
description: "type of the map"
mobile: false
name: "test"
night: true
}
property variant locationTC: QtPositioning.coordinate(44.951, -93.192)
Map {
id: map
activeMapType: map_type
anchors.fill: parent
plugin: osmPlugin
center: locationTC
zoomLevel: 10
copyrightsVisible: false
}
}

Testing QML based app with pytest in python

I would like to test my QML frontend code along with my Python backend code(using PySide2) with Pytest preferably, and be able to send keyClicks, MouseClicks and signals just like pytest-qt plugin does. I have already checked out pytest-qml, but the test code is written via QML, and then only ran via via pytest, but I would like to send events and such from python itself, not QML
Basically, having the python code as such:
"""
Slots, Signals, context class etc etc...
"""
app = QGuiApplication([])
engine = QQmlApplicationEngine()
engine.load(QUrl.fromLocalFile("main.qml"))
app.exec_()
and a simple main.qml file, as such,
import QtQuick 2.15
import QtQuick.Layouts 1.15
import QtQuick.Window 2.2
import QtQuick.Controls 2.15
ApplicationWindow {
id: mywin
width: Screen.desktopAvailableWidth
height: Screen.desktopAvailableHeight
visible: true
FileDialog {
id: openDialog
title: "mydialog"
onAccepted: {
}
}
Button {
objectName: "mybtn"
width: 200
height: 200
id: btn
text: "hello"
onClicked: {
openDialog.open()
}
}
}
I would like to do (pseudo-code)something like
def test_file_open():
#Grab QQuickItem(btn)
#Send mouse event to click btn
#Send string to file dialog
# assert string sent == string selected
The pytest-qt plugin would work, but functions take QWidget and QML deals with QQuickItems, which as far as I know doesnt deal with QWidgets.
Is it even possible, or my only option to test my app slots etc is via the pytest-qml ? Perhaps its the easiest way, but perhaps there are other options :)
Edit:
If you use import Qt.labs.platform 1.1 instead of the import QtQuick.Dialogs 1.3, and force QML to not use native dialog, then just change
# assert myfiledialog.property("fileUrl").toLocalFile() == filename # uses QDialog
assert myfiledialog.property("currentFile").toLocalFile() == filename # using QLabs Dialog
And then using the rest of the code from accepted answer it will work, so apparently its very important that it does not use a native dialog.
If anyone else in the future knows how to make it work with native dialog and using QtQuick.Dialogs 1.3 as the original question presented, it would be nice :). But this is still nice to test overall!

You can use the same API since pytest-qt is based on QtTest. Obviously you must understand the structure of the application, for example that the FileDialog is just a QObject that only manages a QWindow that has the dialog, in addition to managing the positions of the items with respect to the windows.
import os
from pathlib import Path
from PySide2.QtCore import QUrl
from PySide2.QtQml import QQmlApplicationEngine
CURRENT_DIR = Path(__file__).resolve().parent
def build_engine():
engine = QQmlApplicationEngine()
filename = os.fspath(CURRENT_DIR / "main.qml")
url = QUrl.fromLocalFile(filename)
engine.load(url)
return engine
def main():
app = QGuiApplication([])
engine = build_engine()
app.exec_()
if __name__ == "__main__":
main()
import QtQuick 2.15
import QtQuick.Controls 2.15
import QtQuick.Dialogs 1.3
import QtQuick.Layouts 1.15
import QtQuick.Window 2.2
ApplicationWindow {
id: mywin
width: Screen.desktopAvailableWidth
height: Screen.desktopAvailableHeight
visible: true
FileDialog {
id: openDialog
objectName: "myfiledialog"
title: "mydialog"
onAccepted: {
}
}
Button {
id: btn
objectName: "mybtn"
width: 200
height: 200
text: "hello"
onClicked: {
openDialog.open();
}
}
}
import os
from PySide2.QtCore import QCoreApplication, QObject, Qt, QPointF
from PySide2.QtGui import QGuiApplication
from PySide2.QtQuick import QQuickItem
from PySide2.QtWidgets import QApplication
import pytest
from app import build_engine
#pytest.fixture(scope="session")
def qapp():
QCoreApplication.setOrganizationName("qapp")
QCoreApplication.setOrganizationDomain("qapp.com")
QCoreApplication.setAttribute(Qt.AA_DontUseNativeDialogs)
yield QApplication([])
def test_app(tmp_path, qtbot):
engine = build_engine()
assert QCoreApplication.testAttribute(Qt.AA_DontUseNativeDialogs)
with qtbot.wait_signal(engine.objectCreated, raising=False):
assert len(engine.rootObjects()) == 1
root_object = engine.rootObjects()[0]
root_item = root_object.contentItem()
mybtn = root_object.findChild(QQuickItem, "mybtn")
assert mybtn is not None
center = QPointF(mybtn.width(), mybtn.height()) / 2
qtbot.mouseClick(
mybtn.window(),
Qt.LeftButton,
pos=root_item.mapFromItem(mybtn, center).toPoint(),
)
qtbot.wait(1000)
qfiledialog = None
for window in QGuiApplication.topLevelWindows():
if window is not root_object:
qfiledialog = window
assert qfiledialog is not None, QGuiApplication.topLevelWindows()
file = tmp_path / "foo.txt"
file.touch()
filename = os.fspath(file)
for letter in filename:
qtbot.keyClick(qfiledialog, letter, delay=100)
qtbot.wait(1000)
qtbot.keyClick(qfiledialog, Qt.Key_Return)
qtbot.wait(1000)
myfiledialog = root_object.findChild(QObject, "myfiledialog")
assert myfiledialog is not None
assert myfiledialog.property("fileUrl").toLocalFile() == filename
Note: The test may fail if the filedialog uses the native window, you could use tools like pyinput but a simpler option is to use virtualenv.

Using QtCharts in Qt Creator with python

I am using Qt Creator to create a QtQuick program using Python. I want to add the QtCharts module to my QML files, but I get the error message
QML module not found (QtCharts)
In a QtQuick project using C++, one would include QtCharts by adding QT += charts in the .pro file.
Is there a similar command to add in the main.pyproj file?
Note that the program runs correctly when built through the python script, but I want to access the features used by the designer in Qt Creator.
The main.pyproject is as follows:
{"files": ["main.py","frontend/main.qml"]}
The main.py file:
import os
import sys
import PyQt5.QtQml
import PyQt5.QtCore
import PyQt5.QtWidgets
if __name__ == '__main__':
os.environ['QT_QUICK_CONTROLS_STYLE'] = 'Default'
app = PyQt5.QtWidgets.QApplication(sys.argv)
engine = PyQt5.QtQml.QQmlApplicationEngine()
engine.load('frontend/main.qml')
if not engine.rootObjects():
sys.exit(-1)
sys.exit(app.exec_())
the frontend/main.qml file:
import QtQuick 2.12
import QtQuick.Controls 2.13
import QtQuick.Layouts 1.12
import QtCharts 2.10
ApplicationWindow {
id: window
visible: true
title: 'Neuron Network Sandbox'
ChartView {
width: 400
height: 300
antialiasing: true
PieSeries {
id: pieSeries
PieSlice { label: "eaten"; value: 94.9 }
PieSlice { label: "not yet eaten"; value: 5.1 }
}
}
}

QML does not play well with system theme [duplicate]

I have a problem with Toolbar when I use the qml file with PyQt5. The result is not the seem : no background image when mouse is over, image no resize automatically.
I want to know if it's normal.
How can I do for have the same result with PyQt5
The result with qmlscene:
The result with Python:
Thanks you for your help.
File : _test.py
from PyQt5.QtCore import (
pyqtProperty,
pyqtSignal,
pyqtSlot,
QAbstractListModel,
QModelIndex,
QObject,
Qt,
QTimer,
)
from PyQt5.QtGui import QGuiApplication
from PyQt5.QtQml import QQmlApplicationEngine
from PyQt5.QtQuick import QQuickView
class MainWindow(QObject):
def __init__(self, parent=None):
super().__init__(parent)
if __name__ == "__main__":
import sys
app = QGuiApplication(sys.argv)
engine = QQmlApplicationEngine()
engine.quit.connect(app.quit)
main_window = MainWindow()
engine.load("_test.qml")
if not engine.rootObjects():
sys.exit(app.exec_())
sys.exit(app.exec())
File : _test.qml
import QtQuick 2.4
import QtQuick.Layouts 1.1
import QtQuick.Controls 1.3
import QtQuick.Controls.Styles 1.3
ApplicationWindow {
width: 500
height: 200
visible: true
ToolBar {
Layout.fillWidth: true
RowLayout {
anchors.fill: parent
ToolButton {
//width: parent.height
anchors.margins: 4
iconSource: "ico/abacus.png"
}
ToolButton {
width: parent.height
Image {
source: "ico/quitter.png"
anchors.fill: parent
anchors.margins: 4
}
}
ToolButton {
width: parent.height
iconSource: "ico/start.png"
anchors.margins: 4
}
ToolButton {
width: parent.height
Image {
source: "ico/stop.png"
anchors.fill: parent
anchors.margins: 4
}
}
}
}
}

Analyzing the source code of qmlscene and testing with the --apptype option I get the following:
qmlscene _test.qml --apptype gui
qmlscene _test.qml --apptype widgets
So analyzing the fundamental difference is that QApplicacion is being used and not QGuiApplication, so internally it should activate some flag that scales the icons.
Considering the above, the solution is:
from PyQt5.QtCore import QUrl
from PyQt5.QtWidgets import QApplication
from PyQt5.QtQml import QQmlApplicationEngine
if __name__ == "__main__":
import os
import sys
app = QApplication(sys.argv)
engine = QQmlApplicationEngine()
current_dir = os.path.dirname(os.path.realpath(__file__))
file = os.path.join(current_dir, "_test.qml")
engine.load(QUrl.fromLocalFile(file))
if not engine.rootObjects():
sys.exit(-1)
sys.exit(app.exec_())
According to the docs of Qt Quick Controls 1:
Note: We are using QApplication and not QGuiApplication in this
example. Though you can use QGuiApplication instead, doing this will
eliminate platform-dependent styling. This is because it is relying on
the widget module to provide the native look and feel.
So it seems that the scaling of the icons is part of the style of the platform.
Each type of project requires a QXApplication:
Console application: You can use any of the 3 types of QXApplication, but using QCoreApplication is the most optimal since the other QXApplication require that they have a window system that in that case is an unnecessary requirement.
QML Application: It requires at least one QGuiApplication, but for certain ones such as the need to use the styles of each platform it is necessary to use QApplication.
Qt Widgets Application: A QApplication is necessary because QWidgets use the styles of each platform.
The fact that sizes change, is this a problem of QtQuick.Controls 1?
Yes, one of the main differences between QQC1 and QQC2 is that the first one is developed to support desktop platforms so you use the styles, unlike the second one that is designed for embedded systems where the main objective is performance. For more information read Differences with Qt Quick Controls 1
Conclusions:
If you want your GUI made with QML to respect the styles of your desktop platform then you must use QQC1 with QApplication.
If your goal is that the style of your application does not respect the style of the desktop in addition to wanting more performance you should use QQC2 with QGuiApplication.

How to connect Python and QML with PySide2?

I want to write a simple desktop application on Ubuntu and I thought that an easy way was to use Qt with QML as GUI and Python as the language for the logic, since I am somewhat familiar with Python.
Now I am trying for hours to somehow connect the GUI and the logic, but it is not working.
I managed the connection QML --> Python but not the other way around. I have Python classes which represent my data model and I added JSON encode and decode functions. So for now there is no SQL database involved. But maybe a direct connection between QML view and some database would make things easier?
So now some code.
QML --> Python
The QML file:
ApplicationWindow {
// main window
id: mainWindow
title: qsTr("Test")
width: 640
height: 480
signal tmsPrint(string text)
Page {
id: mainView
ColumnLayout {
id: mainLayout
Button {
text: qsTr("Say Hello!")
onClicked: tmsPrint("Hello!")
}
}
}
}
Then I have my slots.py:
from PySide2.QtCore import Slot
def connect_slots(win):
win.tmsPrint.connect(say_hello)
#Slot(str)
def say_hello(text):
print(text)
And finally my main.py:
import sys
from controller.slots import connect_slots
from PySide2.QtWidgets import QApplication
from PySide2.QtQml import QQmlApplicationEngine
if __name__ == '__main__':
app = QApplication(sys.argv)
engine = QQmlApplicationEngine()
engine.load('view/main.qml')
win = engine.rootObjects()[0]
connect_slots(win)
# show the window
win.show()
sys.exit(app.exec_())
This works fine and I can print "Hello!". But is this the best way to do it or is it better to create a class with slots and use setContextProperty to be able to call them directly without adding additional signals?
Python --> QML
I cannot get this done. I tried different approaches, but none worked and I also don't know which one is the best to use. What I want to do is for example show a list of objects and offer means to manipulate data in the application etc.
include Javascript:
I added an additional file application.js with a function just to print something, but it could probably be used to set the context of a text field etc.
Then I tried to use QMetaObject and invokeMethod, but just got errors with wrong arguments etc.
Does this approach make any sense? Actually I don't know any javascript, so if it is not necessary, I would rather not use it.
ViewModel approach
I created a file viewmodel.py
from PySide2.QtCore import QStringListModel
class ListModel(QStringListModel):
def __init__(self):
self.textlines = ['hi', 'ho']
super().__init__()
And in the main.py I added:
model = ListModel()
engine.rootContext().setContextProperty('myModel', model)
and the ListView looks like this:
ListView {
width: 180; height: 200
model: myModel
delegate: Text {
text: model.textlines
}
}
I get an error "myModel is not defined", but I guess that it can't work anyway, since delegates only take one element and not a list.
Is this approach a good one? and if yes, how do I make it work?
Is there a totally different approach to manipulate data in a QML view?
I appreciate your help!
I know the Qt documentation but I am not happy with it. So maybe I am missing something. But PyQt seems to be way more popular than PySide2 (at least google searches seem to indicate that) and PySide references often use PySide1 or not the QML QtQuick way of doing things...

Your question has many aspects so I will try to be detailed in my answer and also this answer will be continuously updated because this type of questions are often asked but they are solutions for a specific case so I am going to take the liberty of giving it a general approach and be specific in the possible scenarios.
QML to Python:
Your method works because the type conversion in python is dynamic, in C++ it does not happen. It works for small tasks but it is not maintainable, the logic must be separated from the view so it should not be dependent. To be concrete, let's say that the printed text will be taken by the logic to perform some processing, then if you modify the name of the signal, or if the data does not depend on ApplicationWindow but on another element, etc. then you will have to change a lot connection code.
The recommended as you indicate is to create a class that is responsible for mapping the data you need your logic and embed it in QML, so if you change something in the view you just change the connection:
Example:
main.py
import sys
from PySide2.QtCore import QObject, Signal, Property, QUrl
from PySide2.QtGui import QGuiApplication
from PySide2.QtQml import QQmlApplicationEngine
class Backend(QObject):
textChanged = Signal(str)
def __init__(self, parent=None):
QObject.__init__(self, parent)
self.m_text = ""
#Property(str, notify=textChanged)
def text(self):
return self.m_text
#text.setter
def setText(self, text):
if self.m_text == text:
return
self.m_text = text
self.textChanged.emit(self.m_text)
if __name__ == '__main__':
app = QGuiApplication(sys.argv)
backend = Backend()
backend.textChanged.connect(lambda text: print(text))
engine = QQmlApplicationEngine()
engine.rootContext().setContextProperty("backend", backend)
engine.load(QUrl.fromLocalFile('main.qml'))
if not engine.rootObjects():
sys.exit(-1)
sys.exit(app.exec_())
main.qml
import QtQuick 2.10
import QtQuick.Controls 2.1
import QtQuick.Window 2.2
ApplicationWindow {
title: qsTr("Test")
width: 640
height: 480
visible: true
Column{
TextField{
id: tf
text: "Hello"
}
Button {
text: qsTr("Click Me")
onClicked: backend.text = tf.text
}
}
}
Now if you want the text to be provided by another element you just have to change the line: onClicked: backend.text = tf.text.
Python to QML:
I can not tell you what you did wrong with this method because you do not show any code, but I do indicate the disadvantages. The main disadvantage is that to use this method you must have access to the method and for that there are 2 possibilities, the first one is that it is a rootObjects as it is shown in your first example or searching through the objectName, but it happens that you initially look for the object, you get it and this is removed from QML, for example the Pages of a StackView are created and deleted every time you change pages so this method would not be correct.
The second method for me is the correct one but you have not used it correctly, unlike the QtWidgets that focus on the row and the column in QML the roles are used. First let's implement your code correctly.
First textlines is not accessible from QML since it is not a qproperty. As I said you must access through the roles, to see the roles of a model you can print the result of roleNames():
model = QStringListModel()
model.setStringList(["hi", "ho"])
print(model.roleNames())
output:
{
0: PySide2.QtCore.QByteArray('display'),
1: PySide2.QtCore.QByteArray('decoration'),
2: PySide2.QtCore.QByteArray('edit'),
3: PySide2.QtCore.QByteArray('toolTip'),
4: PySide2.QtCore.QByteArray('statusTip'),
5: PySide2.QtCore.QByteArray('whatsThis')
}
In the case that you want to obtain the text you must use the role Qt::DisplayRole, whose numerical value according to the docs is:
Qt::DisplayRole 0 The key data to be rendered in the form of text. (QString)
so in QML you should use model.display(or only display). so the correct code is as follows:
main.py
import sys
from PySide2.QtCore import QUrl, QStringListModel
from PySide2.QtGui import QGuiApplication
from PySide2.QtQml import QQmlApplicationEngine
if __name__ == '__main__':
app = QGuiApplication(sys.argv)
model = QStringListModel()
model.setStringList(["hi", "ho"])
engine = QQmlApplicationEngine()
engine.rootContext().setContextProperty("myModel", model)
engine.load(QUrl.fromLocalFile('main.qml'))
if not engine.rootObjects():
sys.exit(-1)
sys.exit(app.exec_())
main.qml
import QtQuick 2.10
import QtQuick.Controls 2.1
import QtQuick.Window 2.2
ApplicationWindow {
title: qsTr("Test")
width: 640
height: 480
visible: true
ListView{
model: myModel
anchors.fill: parent
delegate: Text { text: model.display }
}
}
If you want it to be editable you must use the model.display = foo:
import QtQuick 2.10
import QtQuick.Controls 2.1
import QtQuick.Window 2.2
ApplicationWindow {
title: qsTr("Test")
width: 640
height: 480
visible: true
ListView{
model: myModel
anchors.fill: parent
delegate:
Column{
Text{
text: model.display
}
TextField{
onTextChanged: {
model.display = text
}
}
}
}
}
There are many other methods to interact with Python/C++ with QML but the best methods involve embedding the objects created in Python/C++ through setContextProperty.
As you indicate the docs of PySide2 is not much, it is being implemented and you can see it through the following link. What exists most are many examples of PyQt5 so I recommend you understand what are the equivalences between both and make a translation, this translation is not hard since they are minimal changes.