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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Courier New"">Here’s
an example of the code:</span></b></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Courier New""> </span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">def
searchAndSelect(self, searchString, column=0):</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
#If the user searches for nothing, then return and do nothing</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
if len(searchString)==0:</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
return</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New""> </span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
#get the selection model from the tree view</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
selectionModel=self.obsTreeView.selectionModel()</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
# Find the items in the model.</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
# obsTreeModel is a QStandardItemModel</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
# This part is very fast </span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
items=self.obsTreeModel.findItems(searchString, QtCore.Qt.MatchContains,
column)</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
#select each item</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
# This part is very slow.</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
for item in items:</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">
selectionModel.select(item.index(), selectionModel.Select|selectionModel.Rows)</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">#searchAndSelect</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New""> </span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">Does
anyone have any tips on speeding up the selection part? I’ve tried
blocking the signals of the selection model incase the selectionChanged signal
of QItemSelectionModel is causing a re-draw but it didn’t seem to help.</span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New""> </span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Courier New"">Thanks,<br>
Darryl</span></b></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D"> </span></p>
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<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal"><b><span lang="EN-US" style="font-size:10.0pt;font-family:
"Tahoma","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:10.0pt;
font-family:"Tahoma","sans-serif""> Darryl Wallace
[mailto:<a href="mailto:darryl.wallace@prosensus.ca">darryl.wallace@prosensus.ca</a>] <br>
<b>Sent:</b> April-08-10 2:23 PM<br>
<b>To:</b> '<a href="mailto:pyqt@riverbankcomputing.com">pyqt@riverbankcomputing.com</a>'<br>
<b>Subject:</b> Fast selection of non-contiguous items in QTreeview</span></p>
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<p class="MsoNormal"> </p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D">Hello,</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D"> </span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D">I’ve done some reading and can’t find anything on
non-contiguous selection of items in item views beyond : </span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D"> </span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D">“Selections are made up of <i>selection ranges</i>. These
efficiently maintain information about large selections of items by recording
only the starting and ending model indexes for each range of selected items.
Non-contiguous selections of items are constructed by using more than one
selection range to describe the selection.” - </span><a href="http://doc.trolltech.com/4.6/model-view-selection.html#concepts">http://doc.trolltech.com/4.6/model-view-selection.html#concepts</a><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D"> </span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D">Currently we have implemented a selection of items by scanning
each row in the model to see if it should be “selected” based on
certain criteria. Is there a faster way to do this as looping in Python
through a large (50,000 rows)? When selections can be specified with
selection ranges the selection is fast. However, our worst case scenario
is that every-other item need be selected: 25,000 selection ranges would be
created and then we would just be looping through everything again anyways.</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D"> </span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D">Any ideas?</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D"> </span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D">Thanks,</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D">Darryl</span></p>
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