DIV tag equivalent in Qt Graphics Framework - qt

Question

I am working on a simple desktop application where I have to show a tree structure of folders and files along with other diagrams. For this I chose Qt and python (PySide). I need a structure like below (Forgive me for the bad drawing. But you get the idea):
The folders can be double clicked to expand/shrink. When a folder expands, new child elements need to take more space, and the folders below the current folder must move down. Similarly when the folder is shrunk, the folders below the current folder must come up; just like a standard folder system.
Hence I am in search of a <div> equivalent element in Qt where I can place each directory and all of its children inside that div and the div can expand and shrink. This way I don't have to write code for a re-draw every time the folder is opened/closed. Currently I have to calculate each item's position and place the child items respective to that position. That is a lot of calculation and no of items are > 1000. With a div, I will just re-calculate positions of child items and resize the div. Other divs can then automatically re-draw themselves.
I am not using QTreeView because as I said earlier, I have to draw other diagrams and connect these folders with them. QTreeView will live in its own space (with scroll bar and stuff), and I won't be able to draw lines to connect items in QTreeView and QGraphicsScene.
You can view my current work here in github. Here is the file that has my work.

Answer 1

I'm not sure what you're thinking of "<div>". It's just the most simple HTML container, and it seems to have nothing to do with your goal.
You can use graphics layouts to align items in the scene automatically. Here's how it can be implemented:
from PySide import QtGui, QtCore
class Leaf(QtGui.QGraphicsProxyWidget):
def __init__(self, path, folder = None):
QtGui.QGraphicsProxyWidget.__init__(self)
self.folder = folder
label = QtGui.QLabel()
label.setText(QtCore.QFileInfo(path).fileName())
self.setWidget(label)
self.setToolTip(path)
self.setAcceptedMouseButtons(QtCore.Qt.LeftButton)
def mousePressEvent(self, event):
if self.folder:
self.folder.toggleChildren()
class Folder(QtGui.QGraphicsWidget):
def __init__(self, path, isTopLevel = False):
QtGui.QGraphicsWidget.__init__(self)
self.offset = 32
childrenLayout = QtGui.QGraphicsLinearLayout(QtCore.Qt.Vertical)
childrenLayout.setContentsMargins(self.offset, 0, 0, 0)
flags = QtCore.QDir.AllEntries | QtCore.QDir.NoDotAndDotDot
for info in QtCore.QDir(path).entryInfoList(flags):
if info.isDir():
childrenLayout.addItem(Folder(info.filePath()))
else:
childrenLayout.addItem(Leaf(info.filePath()))
self.childrenWidget = QtGui.QGraphicsWidget()
self.childrenWidget.setLayout(childrenLayout)
mainLayout = QtGui.QGraphicsLinearLayout(QtCore.Qt.Vertical)
mainLayout.setContentsMargins(0, 0, 0, 0)
self.leaf = Leaf(path, self)
mainLayout.addItem(self.leaf)
mainLayout.addItem(self.childrenWidget)
if isTopLevel:
mainLayout.addStretch()
self.setLayout(mainLayout)
def paint(self, painter, option, widget):
QtGui.QGraphicsWidget.paint(self, painter, option, widget)
if self.childrenWidget.isVisible() and self.childrenWidget.layout().count() > 0:
lastChild = self.childrenWidget.layout().itemAt(self.childrenWidget.layout().count() - 1)
lastChildY = self.childrenWidget.geometry().top() + \
lastChild.geometry().top() + self.leaf.geometry().height() / 2;
painter.drawLine(self.offset / 2, self.leaf.geometry().bottom(), self.offset / 2, lastChildY)
for i in range(0, self.childrenWidget.layout().count()):
child = self.childrenWidget.layout().itemAt(i)
childY = self.childrenWidget.geometry().top() + \
child.geometry().top() + self.leaf.geometry().height() / 2
painter.drawLine(self.offset / 2, childY, self.offset, childY)
def toggleChildren(self):
if self.childrenWidget.isVisible():
self.layout().removeItem(self.childrenWidget)
self.childrenWidget.hide()
self.leaf.widget().setStyleSheet("QLabel { color : blue; }")
print "hide"
else:
self.childrenWidget.show()
self.layout().insertItem(1, self.childrenWidget)
self.leaf.widget().setStyleSheet("")
self.update()
if __name__ == "__main__":
import sys
app = QtGui.QApplication(sys.argv)
scene = QtGui.QGraphicsScene()
view = QtGui.QGraphicsView(scene)
# put your root path here
scene.addItem(Folder("/usr/share/alsa", True))
view.show()
view.resize(400, 400)
sys.exit(app.exec_())