19
votes
Accepted
Make QGIS python plugin for both versions 2.x and 3.x?
Documentation
Here you can find what is new and what is break under the PyQGIS API.
To get details about how to port Python2 to Python3 go there
You can find some detail about testing from QGIS2 to ...
- 2,231
13
votes
Accepted
QComboBox multiple selection - PyQT5
For anyone interested, here is an implementation of a CheckableComboBox.
class CheckableComboBox(QComboBox):
# Subclass Delegate to increase item height
class Delegate(QStyledItemDelegate):
...
13
votes
Accepted
NameError: name 'QMessageBox' is not defined
This is a bug in NNJoin plugin.
Open NNJoin_gui.py file located in "/Users/joanlee/Library/Application Support/QGIS/QGIS3/profiles/default/python/plugins/NNJoin/" using an editor.
Add ...
- 3,439
10
votes
PyQt signal when layer name is changed in PyQGIS
Use the nameChanged signal of QgsLayerTreeNode class.
from qgis.core import QgsProject
def name_changed(node, name):
print(f"New Name: {name}")
QgsProject.instance().layerTreeRoot()...
- 77.8k
9
votes
Accepted
Using a custom UI for a QGIS processing algorithm script
I don't see the practical side of creating classes inside other classes. Just split it.
Below is how I will make your code work :
import os
from PyQt5 import uic
from PyQt5.QtWidgets import QWidget
...
- 15.9k
8
votes
Accepted
QGIS ImportError: No module named 'PyQt5.QtSvg'
You're missing the python3-pyqt5.qtsvg dependency. Install that and retry.
- 27.8k
8
votes
Accepted
Opening embedded canvas in new window with all layers
Review this script. It creates a new QMainWindow and moves the existing map canvas to that window. I've made some changes. Firstly, add a file path (to QgsVectorLayer) to be displayed in map canvas.
...
- 77.8k
8
votes
Accepted
Getting point geometry by clicking at the map within QGIS plugin
Change
super(self, QgsMapTool).__init__(self, canvas)
to
super(QgsMapTool, self).__init__(canvas)
- 77.8k
7
votes
Accepted
Emitting signal when project property is changed using PyQGIS
Yes, there is a way. It's the customVariablesChanged signal from QgsProject.
def my_slot():
print("A project variable was just changed!")
QgsProject.instance().customVariablesChanged....
- 36.7k
7
votes
Accepted
Counting seconds using QTimer in PyQGIS
For what you are trying to do, QTimer.singleShot() is not really what you want. I would suggest setting an interval, then connecting your slot function to the timeout signal of QTimer and calling ...
- 22.6k
6
votes
Accepted
Compatibility PyQt5 and PyQt4
I'm assuming when you say "PyQt5", you mean you are using QGIS 3.x. In which case:
layer.pendingFields()
becomes:
layer.fields()
And:
layer = QgsMapLayerRegistry.instance().mapLayersByName('...
- 76.1k
6
votes
Accepted
How to put QgsCheckableComboBox() into standby
You can add the combobox to a dialog window. After closing the dialog, print prints the selected items.
from qgis.PyQt import QtGui
from qgis.core import *
planet_list = ["Venus", "...
- 77.8k
6
votes
Developing QGIS plugin: AttributeError: object has no attribute
In new_mmqgis.py:
You set self.first_start = True in initGui, then, you set self.first_start = False in run method.
In geocode_web_service method, you are checking if self.first_start == True. That if ...
- 77.8k
5
votes
Accepted
No custom widgets in Qt Designer for QGIS 3
The environment and path needs to be set for Qt Designer to access the QGIS Custom widgets. These can be set by running the "qgis-designer.bat" file that comes with a QGIS installation. For a ...
- 997
5
votes
No custom widgets in Qt Designer for QGIS 3
In QGIS 3.2.0, custom widgets seem to be available:
Tested on Windows 7 64-bit.
Edit:
I used the QGIS Standalone Installer Version 3.2 (64 bit) and following the simple on-screen instructions. Once ...
- 76.1k
5
votes
How to get the selected value in a value map with Function Editor in QGIS 3.0.2?
You need to connect your LIVSMILJO comboBox to a signal and return the current text of LIVSMILJO comboBox every time selection of text changes in LIVSMILJO comboBox.This can be done as follows
def ...
- 1,634
5
votes
Accepted
QPSQL driver on kubuntu 18.04
Solved by installing the library libqt5sql5-psql
sudo apt install libqt5sql5-psql
- 1,357
5
votes
Accepted
Get xy coordinates of QgsMapCanvas in PyQGIS 3?
You don't need to define lambda function and to specify self.canvas.scale() and self.canvas.xyCoordinates(). Because scaleChanged event passes scale and xyCoordinates passes coordinates to the related ...
- 77.8k
5
votes
Accepted
QGIS2 to QGIS3 plugin migration issue AttributeError: type object 'QObject' has no attribute 'connect'
With this documentation about PyQt5 signals, try this :
self.buttonBox.accepted.connect(Configuration.accept)
self.buttonBox.rejected.connect(Configuration.reject)
- 15.9k
5
votes
Accepted
Displaying QgsMessageBar from plugin
I don't know how to do that in Qt Designer, but in PyQGIS directly, it is an easiest way :
my_dlg = QDialog()
my_dlg.resize(500, 300)
my_dlg_lyt = QVBoxLayout(my_dlg)
my_msg_bar = QgsMessageBar(my_dlg)...
- 15.9k
5
votes
PyQGIS: Querying PostGIS Table
As you have specified the geometry column (geom) in uri.setDataSource(), you need to select the geom column along with the id_ruas column.
nb = 1050130
fields = 'id_ruas, geom' -- include geom in ...
- 17.7k
4
votes
Accepted
Problem running PyQt code in Qgis3
In QGIS you can't use an application object, because qgis itself is a QtApplication. Try to execute lines 6-10 alone and you'll see a widget on the screen. To have a full functional dialog, you'll ...
- 2,632
4
votes
Accepted
How to open and add SQLite connection to browser with PyQgis
I have found an answer:
con = ['name_of_db','C:\\path_to_db\\andorra.sqlite']
QSettings().setValue("SpatiaLite/connections/%s/sqlitepath" %(con[0]), con[1])
iface.reloadConnections()
This code will ...
- 459
4
votes
Accepted
QGIS plugin mouseClickEvent
This is really more of a IT/ PyQt question, so I will provide an answer in the context of QGIS plugin development, to try to keep on topic.
The reason your mousePressEvent does nothing is that you ...
- 22.6k
4
votes
Accepted
Hook two horizontal slider each other - PyQt5
Test-it in another method like that :
def run (self):
self.dlg = Dialog()
self.dlg.horizontalSlider.sliderMoved.connect(lambda v: self.adjust_sliders(1, v))
self.dlg.horizontalSlider_2....
- 15.9k
4
votes
NameError: name 'QMessageBox' is not defined
You should import QMessageBox from PyQt
from qgis.PyQt.QtWidgets import QMessageBox
- 375
4
votes
Efficient filtering of many options in QGIS Plugin
Perhaps you could loop through the checkboxes, using the isChecked() method to ascertain whether they are checked and if so, set all combobox items to checked. Then eventually, get all the checked ...
- 17.7k
4
votes
Accepted
Using pyqtSignal in emitting signal for maptool in QGIS
You just forgot to add self as the first argument of your onMapClick() method. The class instance object needs to be the first argument of all class methods. The canvasClicked() signal also emits the ...
- 22.6k
4
votes
Accepted
"TypeError: disconnect failed beetween 'accepted' and 'save'" error when creating custom feature form with PyQGIS
I concur that there seems to be an issue with disconnecting the save() and resetValues() slots from the accepted and rejected signals of the QDialogButtonBox of QgsAttributeForm. Indeed, perusing the ...
- 22.6k
4
votes
QgsFileWidget mandatory field in QWizard issue
Try to pass the third parameter as string which refers property name, filePath here.
self.wizardPage.registerField('projPath*', self.projPath, 'filePath', self.projPath.fileChanged)
Here is a working ...
- 77.8k
Only top scored, non community-wiki answers of a minimum length are eligible