QGIS Python Console – How to Clear Using PyQGIS

pyqgisqgis-python-console

I'm developing a python script in which I use several "print" statements to view the intermediate results in python console of QGIS. Each time after executing the program, I have to manually clear the python console using "Clear Console" option.

Is there a way out to clear the printed statements in python console using a command?

I tried using the following command from this answer

qgis.console.clearConsole()

But I am getting this error message

AttributeError: 'module' object has no attribute 'console'

Best Answer

QGIS offers you several classes for logging messages into the Log Messages Panel (i.e., no need to print debug messages from your plugin into the QGIS Python console). You could even easily create a tab in such a panel exclusively for your plugin using QgsMessageLog class:

from qgis.core import Qgis
QgsMessageLog.logMessage( "Info message from plugin", "My Plugin", Qgis.Info )
QgsMessageLog.logMessage( "My warning message", "My Plugin", Qgis.Warning )
QgsMessageLog.logMessage( "My critical message!!!", "My Plugin", Qgis.Critical )
QgsMessageLog.logMessage( "My success message", "My Plugin", Qgis.Success )

Having said that, you can clear the QGIS Python console with these 3 lines:

from qgis.PyQt.QtWidgets import QDockWidget
consoleWidget = iface.mainWindow().findChild( QDockWidget, 'PythonConsole' )
consoleWidget.console.shellOut.clearConsole()

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You need to access the attributes of the features of the table.

lyr = iface.activeLayer()

features = lyr.getFeatures()

for ft in features:
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    print attrs

To access first column use

print attrs[0]

Column names can be add with:

lyr = iface.activeLayer()

features = lyr.getFeatures()
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[GIS] Set print composer to map canvas extent using python

Thanks Joseph, that worked perfectly. I've shown the completed code below for reference.

import os,sys
from qgis.core import*
from PyQt4.QtCore import*
from qgis.utils import*
from qgis.gui import *
import qgis
from PyQt4.QtXml import *

canvas = qgis.utils.iface.mapCanvas()
layers = canvas.layers()

myFile = os.path.join('P:\Office Admin\GIS\Templates\Plan templates\QGIS template plans\Title deed templates', 'A0_landscape_title deed.qpt')
myTemplateFile = file(myFile, 'rt')
myTemplateContent = myTemplateFile.read()
myTemplateFile.close()
myDocument = QDomDocument()
myDocument.setContent(myTemplateContent, False)
comp = iface.createNewComposer()
comp.composition().loadFromTemplate(myDocument)

map_item = comp.composition().getComposerItemById('Map 1')
map_item.setMapCanvas(canvas)
map_item.zoomToExtent(canvas.extent())

Note: If you do not set the Item ID in the "Item properties - Item ID" panel and save this as part of your template before running the code, the following error will occur:

Error: 'NoneType' object has no attribute 'setMapCanvas'

Your Item ID should correspond to that specified in the code - for this example the Item ID is Map 1.

Best Answer

Related Solutions

[GIS] Print values from Tables in QGIS Console

[GIS] Set print composer to map canvas extent using python

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