[PyQt] Resize columns in QTreeView

[Gionata Boccalini]

Hi, I am doing a  small file browser with 2 QTreeView (treeView and 
fileView) linked with 2 different QFileSystemModel (dirModel and 
fileModel): when the user selects a folder on the left view I want the 
contents of that folder to be displayed in the right view, (only the 
files are shown in the right view while only folder are shown in the 
left view...).
This is the constructor method, in short:

class FileBrowser(QWidget):
     def __init__(self, parent = None):
         super(FileBrowser, self).__init__(parent)
         self.treeView = QtGui.QTreeView()
         self.treeView.setSortingEnabled (True)
         self.dirModel = QtGui.QFileSystemModel()
         self.dirModel.setFilter(QDir.AllDirs | QDir.NoDotAndDotDot)
         self.treeView.setModel(self.dirModel)

         # Path
         rootindex = self.dirModel.setRootPath(QDir.rootPath())
         homeindex = self.dirModel.index(QDir.homePath())

         self.treeView.setRootIndex(rootindex)
         self.treeView.scrollTo(homeindex,  
QtGui.QAbstractItemView.PositionAtTop)
         self.treeView.expand(homeindex)
         self.treeView.resizeColumnToContents(0)
         self.treeView.sortByColumn(0, Qt.AscendingOrder)

         sizePolicy = QSizePolicy(QSizePolicy.Expanding, 
QSizePolicy.Expanding)
         self.treeView.setSizePolicy(sizePolicy)
         self.treeView.setAlternatingRowColors(True)
         self.treeView.setAnimated(True)
         self.treeView.hideColumn(1)
         self.treeView.hideColumn(2)

         ....
         self.fileModel = QtGui.QFileSystemModel()
         #self.fileModel.setFilter(QDir.Files)
         self.fileView = QtGui.QTreeView()
         self.fileView.setModel(self.fileModel)
         self.fileModel.setRootPath(QDir.rootPath())
         homeindex = self.fileModel.index(QDir.homePath())

         .......
         ....

         self.fileView.setRootIndex(homeindex)
         self.fileView.setSizePolicy(sizePolicy)
         self.fileView.setSortingEnabled (True)
         self.fileView.sortByColumn(2, Qt.AscendingOrder)
         self.fileView.setAlternatingRowColors(True)
         self.fileView.setAnimated(True)

         # Signals
         self.treeView.clicked.connect(self.updateFiles)
         ...
         ...



The problem is the resizeColumnToContents(0) method of QtreeView, which 
is called in a slot on the "clicked" QTreeView signal: when I click on 
the folder in the left view the first column is resized, but the first 
column of the right view is resized only on the second click on the same 
folder (on the left view.... quite tricky to explain....)!!!
This is the code I am using in the slot for the clicked() signal:

  @QtCore.pyqtSlot('QModelIndex')
     def updateFiles(self,  index):
         path = self.dirModel.filePath(index)
         fileIndex = self.fileModel.index(path)
         self.fileView.setRootIndex(fileIndex)

         self.treeView.resizeColumnToContents(0)
         self.fileView.resizeColumnToContents(0)


The first column shrinks only on the second click, so on the second 
signal...
If I comment out the line  self.fileView.setRootIndex(fileIndex) the 
resize goes as it should, but the treeView is not updated with the new 
files..
Maybe there is a better way to do it all, but I haven't found a good 
example on the net, so I am trying to do that myself. Anyway I hope I've 
explained it well...
Thanks for your help, and you time!!!!

-- 
Gionata Boccalini