[GIS] How to use PyQGIS ( Python QGIS API ) to open/close Update Drawing Order checkbox in QGIS2’s Layers (Legend Interface)

legendpythonqgisqgis-2rendering

Thanks qgis 2, the Legend Interface (layers dockwidget) now has Update Drawing Order check box on right-click mouse context menu. I think this feature can let user temporally closes rendering, then changes order of layers without no-used rendering.
And how to use PyQGIS control this feature??

Btw, the PyQGIS API iface.legendInterface().moveLayer( layer, group_index )
in qgis, group_index include any layer and group (on top level?), but
in qgis2, group_index just include group

e.g. If the layer/group structure:

--layer1  
--group1  
  --layer2  
  --layer3

To move layer1 to group 1
in qgis, use qgis.utils.iface.legendInterface().moveLayer( layer1, 1 )
in qgis2, use iface.legendInterface().moveLayer( layer1, 0 )

Edit:
I use moveLayer, but mapCanvas doesn't refresh, even I use mapCanvas.refresh()

iface.legendInterface().moveLayer( iface.activeLayer(), 0) # activeLayer move to top of gruop in layer legend, but mapCanvas doesn't refresh
iface.mapCanvas().refresh() #nothing happened

But I uncheck and then check Update Drawing Order, it works.
How could I refresh mapCanvas after layer moved??
If I can use PyQGIS to uncheck and check Update Drawing Order, it will work.

Best Answer

To stop rendering you need to call:

canvas.freeze(True)

then to undo:

canvas.freeze(False)
canvas.refresh()

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[GIS] How to use raw_input() in QGIS python console

The alternative to raw_input is QInputDialog.getText as explained in Maximus' answer above. A quick and Dirty example would be:

##Import libraries
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from qgis.core import *
from qgis.gui import *
from qgis.utils import *

from PyQt4.QtGui import QInputDialog #this is for your dialogs

 tempTuple = QInputDialog.getText(None, "Your Name" ,"Enter your Full Name: ")
 userName = tempTuple[0]

[GIS] Print Composer Map with Table using PyQGIS

Which version of QGIS are you using? If it's 2.4, you can set the columns shown in a QgsComposerAttributeTable by using the setColumns method. This method takes a list of QgsComposerTableColumn. Here's an example

#create a composition and composer attribute table
composition = QgsComposition(iface.mapCanvas().mapSettings())
table = QgsComposerAttributeTable(composition)

#create columns for the table
col1 = QgsComposerTableColumn()
col1.setAttribute('feature_id')
col2 = QgsComposerTableColumn()
col2.setAttribute('feature_name')

#set table columns
table.setColumns([col1, col2])

There's a bunch of other things you can set for columns, such as the heading, alignment and sort order (see api docs here). You can even set an expression for a column in place of the attribute for added flexibility.

edit: To show only certain features you can set a filter on the table:

table.setFeatureFilter("id in (1,2,3)")
table.setFilterFeatures( True )

So, to filter a table to only selected features:

#get current layer
current_layer = qgis.utils.iface.mapCanvas().currentLayer()
#get list of selected feature ids
selected_ids = [f.id() for f in current_layer.selectedFeatures()]
#convert list to string
filter_id_string = ','.join([str(id) for id in selected_ids])
#filter table
table.setFeatureFilter("$id in (" + filter_id_string + ")")
table.setFilterFeatures( True )

update: I missed a character in the filter expression. It should have been "$id in (...". Here's a complete, working version of the code you posted. There was a few simple mistakes (the constructor for QgsLegendModel takes no arguments, there's no applyDefaultSize method for attribute tables, and I've also moved the attribute table setItemPosition line):

from PyQt4.QtCore import *
from PyQt4.QtGui import *

layer = qgis.utils.iface.activeLayer()

qgis.utils.iface.actionZoomToSelected().trigger()
qgis.utils.iface.mapCanvas().zoomScale(1000)

mapRenderer = iface.mapCanvas().mapRenderer()
c = QgsComposition(mapRenderer)
c.setPlotStyle(QgsComposition.Print)
x, y = 0, 0
w, h = c.paperWidth(), c.paperHeight()
composerMap = QgsComposerMap(c, x,y,w*.75,h)
c.addItem(composerMap)

legend = QgsComposerLegend(c)
c.addComposerLegend(legend)
legend.model().setLayerSet(mapRenderer.layerSet())
legend.setTitle('')

legendModel = QgsLegendModel()
legendModel.setLayerSet([layer.id()])

legend.updateLegend()

selected_ids = [f.id() for f in layer.selectedFeatures()]
filter_id_string = ','.join([str(id) for id in selected_ids])

table = QgsComposerAttributeTable(c)
table.setItemPosition(x+50, y+50)
table.setVectorLayer(layer)
table.setMaximumNumberOfFeatures(20)
table.setFeatureFilter("$id in (" + filter_id_string + ")")
table.setFilterFeatures(True)
col1 = QgsComposerTableColumn()
col1.setAttribute('Diametre')
col1.setHeading("Diametre")
col2 = QgsComposerTableColumn()
col2.setAttribute('Nature')
col2.setHeading("Nature")
table.setColumns([col1, col2])
c.addItem(table)

printer = QPrinter()
printer.setOutputFormat(QPrinter.PdfFormat)
printer.setOutputFileName('out.pdf')
printer.setPaperSize(QSizeF(c.paperWidth(), c.paperHeight()), QPrinter.Millimeter)
printer.setFullPage(True)
printer.setColorMode(QPrinter.Color)
printer.setResolution(c.printResolution())
pdfPainter = QPainter(printer)
paperRectMM = printer.pageRect(QPrinter.Millimeter)
paperRectPixel = printer.pageRect(QPrinter.DevicePixel)
c.render(pdfPainter, paperRectPixel, paperRectMM)
pdfPainter.end()

Best Answer

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