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Problem with GridLayout widget stretching/sizing

I'm trying to make a simple image editor GUI using the GridLayout. However, I am coming across a problem where the ratios between the image and the side panels are not what I want them to be. Currently, my code is:
import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class Window(QMainWindow):
def __init__(self, parent = None):
super().__init__(parent)
self.setWindowTitle("PyEditor")
self.setGeometry(100, 100, 500, 300)
self.centralWidget = QLabel()
self.setCentralWidget(self.centralWidget)
self.gridLayout = QGridLayout(self.centralWidget)
self.createImagePanel()
self.createDrawPanel()
self.createLayerPanel()
def createImagePanel(self):
imageLabel = QLabel(self)
pixmap = QPixmap('amongus.png')
imageLabel.setPixmap(pixmap)
self.gridLayout.addWidget(imageLabel, 0, 0, 3, 4)
def createDrawPanel(self):
drawPanel = QLabel(self)
drawLayout = QVBoxLayout()
drawPanel.setLayout(drawLayout)
tabs = QTabWidget()
filterTab = QWidget()
drawTab = QWidget()
tabs.addTab(filterTab, "Filter")
tabs.addTab(drawTab, "Draw")
drawLayout.addWidget(tabs)
self.gridLayout.addWidget(drawPanel, 0, 4, 1, 1)
def createLayerPanel(self):
layerPanel = QLabel(self)
layerLayout = QVBoxLayout()
layerPanel.setLayout(layerLayout)
tab = QTabWidget()
layerTab = QWidget()
tab.addTab(layerTab, "Layers")
layerLayout.addWidget(tab)
self.gridLayout.addWidget(layerPanel, 1, 4, 1, 1)
if __name__ == "__main__":
app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())
This gives me the following window:
When I resize the window, only the filter/draw and layer panels are stretching, and not the image panel. I want to image panel to stretch as well and take up the majority of the window instead.

While theoretically every Qt widget could be used as a container, some widgets should not be used for such a purpose, as their size hints, size policies and resizing have different and specific behavior depending on their nature.
QLabel is intended as a display widget, not as a container. Everything related to its size is based on the content (text, image or animation), so the possible layout set for it will have no result in size related matters and will also create some inconsistencies in displaying the widgets added to that layout.
If a basic container is required, then basic QWidget is the most logical choice.
Then, if stretching is also a requirement, that should be applied using the widget or layout stretch factors. For QGridLayout, this is achieved by using setColumnStretch() or setRowStretch().
Trying to use the row or column span is not correct for this purpose, as the spanning only indicates how many grid "cells" a certain layout item will use, which only makes sense whenever there are widgets that should occupy more than one "cell", exactly like the spanning of a table.
So, the following changes are required to achieve the wanted behavior:
change all QLabel to QWidget (except for the label that shows the image, obviously);
use the proper row/column spans; the imageLabel should be added with only one column span (unless otherwise required):
self.gridLayout.addWidget(imageLabel, 0, 0, 3, 1, alignment=Qt.AlignCenter)
set a column stretch of (at least) 1 for the first column:
self.gridLayout.setColumnStretch(0, 1)
if you want the image to be center aligned in the available space, set the alignment on the widget (not when adding it to the layout):
imageLabel = QLabel(self, alignment=Qt.AlignCenter)
Note that all the above will not scale the image whenever the available size is greater than that of the image. While you can set the scaledContents to True, the result will be that the image will be stretched to fill the whole available space, and unfortunately QLabel doesn't provide the ability to keep the aspect ratio. If you need that, then it's usually easier to subclass QWidget and provide proper implementation for size hint and paint event.
class ImageViewer(QWidget):
_pixmap = None
def __init__(self, pixmap=None, parent=None):
super().__init__(parent)
self.setPixmap(pixmap)
def setPixmap(self, pixmap):
if self._pixmap != pixmap:
self._pixmap = pixmap
self.updateGeometry()
def sizeHint(self):
if self._pixmap and not self._pixmap.isNull():
return self._pixmap.size()
return super().sizeHint()
def paintEvent(self, event):
if self._pixmap and not self._pixmap.isNull():
qp = QPainter(self)
scaled = self._pixmap.scaled(self.width(), self.height(),
Qt.KeepAspectRatio, Qt.SmoothTransformation)
rect = scaled.rect()
rect.moveCenter(self.rect().center())
qp.drawPixmap(rect, scaled)

Initially moved scroll bar inside QGraphics

I am trying to set the vertical and horizontal scroll bars initially moved inside a QGraphicsScene widget. The following code should move the bars and set them in the middle, but they are not moved:
from PyQt5 import QtCore, QtGui, QtWidgets
import sys
class Diedrico(QtWidgets.QWidget):
def paintEvent(self, event):
qp = QtGui.QPainter(self)
pen = QtGui.QPen(QtGui.QColor(QtCore.Qt.black), 5)
qp.setPen(pen)
qp.drawRect(500, 500, 1000, 1000)
class UiVentana(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(UiVentana, self).__init__(parent)
self.resize(1000, 1000)
self.setFixedSize(1000, 1000)
self.scene = QtWidgets.QGraphicsScene(self)
self.view = QtWidgets.QGraphicsView(self.scene)
# This two lines should move the scroll bar
self.view.verticalScrollBar().setValue(500)
self.view.horizontalScrollBar().setValue(500)
self.diedrico = Diedrico()
self.diedrico.setFixedSize(2000, 2000)
self.scene.addWidget(self.diedrico)
self.setCentralWidget(self.view)
def keyPressEvent(self, event):
if event.key() == QtCore.Qt.Key_R:
self.view.setTransform(QtGui.QTransform())
elif event.key() == QtCore.Qt.Key_Plus:
scale_tr = QtGui.QTransform()
scale_tr.scale(1.5, 1.5)
tr = self.view.transform() * scale_tr
self.view.setTransform(tr)
elif event.key() == QtCore.Qt.Key_Minus:
scale_tr = QtGui.QTransform()
scale_tr.scale(1.5, 1.5)
scale_inverted, invertible = scale_tr.inverted()
if invertible:
tr = self.view.transform() * scale_inverted
self.view.setTransform(tr)
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
ui = UiVentana()
ui.show()
sys.exit(app.exec_())
I could move the bars when I used a scroll area such as in this question

The answer given by #S.Nick works fine, but I'd like to add some insight about why you are facing this issue and what's happening "under the hood".
First of all, in your code you try to set the values of the scroll bars before adding any object to the scene.
At that point, you just created the view and the scene. The view widget has not been shown (so it doesn't "know" its actual size yet), and the scene is empty, meaning that the sceneRect is null, as in 0 width and 0 height: in this scenario, the scroll bars have a maximum value of 0, and setting any value won't give any result.
NOTE: There is a very important aspect to keep in mind: unless
explicitly declared or requested, the sceneRect of a
QGraphicsScene is always null until a view shows it. And by
"requested" I mean that even just calling scene.sceneRect() is
enough to ensure that the scene actually and finally "knows" its
extent.
After trying to set the scroll bars (with no results), you added the widget to the scene. The problem is that a view (which is a QAbstractScrollArea descendant) only updates its scrollbars as soon as it's actually mapped on the screen.
This is a complex "path" that starts from showing the main parent window (if any), which, according to its contents resizes itself and, again, resizes its contents if they require it, eventually based on their [nested widget] size policies. Only then, the view "decides" if scrollbars are needed, and eventually sets their maximum. And, only then you can actuall set a value for those scroll bars, and that's because only then the view "asks" the scene about its sceneRect.
This also (partially) explains why the view behaves in different way than a standard scroll area: widgets have a sizeHint that is used by the QWidget that contains them inside the scroll area, and, theoretically, their size is mapped as soon as they're created. But. this depends on their size hints and policies, so you cannot guarantee the actual scroll area contents size until it's finally mapped/shown; long story short: it "works", but not perfectly - at least not until everything has finally been shown.
A test example
There are different ways to solve your problem, according to your needs and implementation.
Set the sceneRect independently, even before adding any object to the scene (but if those objects boundaries go outside the scene, you'll face some inconsistency)
Call scene.sceneRect() as explained above, after adding all objects
Set the scoll bars only after the view has been shown and resized
I've prepared an example that shows the three situations explained above. It will create a new view and update its scrollbars at different points according to the checkboxes, to show how differently they behave. Note that when setting the sceneRect I used a rectangle smaller than the widget size to better display its behavior: you can see that the visual result of "Set scene rect" and "Check scene rect" is similar, but the scroll bar positions are different.
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
class Diedrico(QtWidgets.QWidget):
def paintEvent(self, event):
qp = QtGui.QPainter(self)
pen = QtGui.QPen(QtGui.QColor(QtCore.Qt.black), 5)
qp.setPen(pen)
qp.drawRect(500, 500, 1000, 1000)
class TestView(QtWidgets.QGraphicsView):
def __init__(self, setRect=False, checkScene=False, showEventCheck=False):
super(TestView, self).__init__()
self.setFixedSize(800, 800)
scene = QtWidgets.QGraphicsScene()
self.setScene(scene)
self.diedrico = Diedrico()
self.diedrico.setFixedSize(2000, 2000)
scene.addWidget(self.diedrico)
if setRect:
scene.setSceneRect(0, 0, 1500, 1500)
elif checkScene:
scene.sceneRect()
self.showEventCheck = showEventCheck
if not showEventCheck:
self.scroll()
def scroll(self):
self.verticalScrollBar().setValue(500)
self.horizontalScrollBar().setValue(500)
def showEvent(self, event):
super(TestView, self).showEvent(event)
if not event.spontaneous() and self.showEventCheck:
self.scroll()
class ViewTester(QtWidgets.QWidget):
def __init__(self):
QtWidgets.QWidget.__init__(self)
layout = QtWidgets.QVBoxLayout()
self.setLayout(layout)
self.setRectCheck = QtWidgets.QCheckBox('Set scene rect')
layout.addWidget(self.setRectCheck)
self.checkSceneCheck = QtWidgets.QCheckBox('Check scene rect')
layout.addWidget(self.checkSceneCheck)
self.showEventCheck = QtWidgets.QCheckBox('Scroll when shown')
layout.addWidget(self.showEventCheck)
showViewButton = QtWidgets.QPushButton('Show view')
layout.addWidget(showViewButton)
showViewButton.clicked.connect(self.showView)
self.view = None
def showView(self):
if self.view:
self.view.close()
self.view.deleteLater()
self.view = TestView(
setRect = self.setRectCheck.isChecked(),
checkScene = self.checkSceneCheck.isChecked(),
showEventCheck = self.showEventCheck.isChecked()
)
self.view.show()
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
viewTester = ViewTester()
viewTester.show()
sys.exit(app.exec_())
Finally, remember that using absolute values for scrollbars is not a good idea. If you want to "center" the view, consider using centerOn (and its item based overload), or set values based on scrollBar.maximum()/2.

You want to set the value when the widget is not yet formed, make it a moment.
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
class Diedrico(QtWidgets.QWidget):
def paintEvent(self, event):
qp = QtGui.QPainter(self)
pen = QtGui.QPen(QtGui.QColor(QtCore.Qt.black), 5)
qp.setPen(pen)
qp.drawRect(500, 500, 1000, 1000)
class UiVentana(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(UiVentana, self).__init__(parent)
self.resize(1000, 1000)
self.setFixedSize(1000, 1000)
self.scene = QtWidgets.QGraphicsScene(self)
self.view = QtWidgets.QGraphicsView(self.scene)
# This two lines should move the scroll bar
QtCore.QTimer.singleShot(0, self.set_Value) # +++
self.diedrico = Diedrico()
self.diedrico.setFixedSize(2000, 2000)
self.scene.addWidget(self.diedrico)
self.setCentralWidget(self.view)
def set_Value(self): # +++
self.view.verticalScrollBar().setValue(500)
self.view.horizontalScrollBar().setValue(500)
def keyPressEvent(self, event):
if event.key() == QtCore.Qt.Key_R:
self.view.setTransform(QtGui.QTransform())
elif event.key() == QtCore.Qt.Key_Plus:
scale_tr = QtGui.QTransform()
scale_tr.scale(1.5, 1.5)
tr = self.view.transform() * scale_tr
self.view.setTransform(tr)
elif event.key() == QtCore.Qt.Key_Minus:
scale_tr = QtGui.QTransform()
scale_tr.scale(1.5, 1.5)
scale_inverted, invertible = scale_tr.inverted()
if invertible:
tr = self.view.transform() * scale_inverted
self.view.setTransform(tr)
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
ui = UiVentana()
ui.show()
sys.exit(app.exec_())

Set widget width based on its height

I am trying to find a way to have one of my widgets maintain a width based on its height. I have other widgets working fine reimplementing the heightForWidth method. That was easy because that method is standard. I know there is no included widthForHeight method so I have tried many options the internet has suggested but have not gotten anything to work all the way. What I currently have almost gets me there.
I first reimplement my widget's sizeHint to get its width to be a ratio of its parent's (QHBoxLayout) height.
The sizeHint makes MyCustomLabel show with the right size at first show but did not update during times the user resized the window. I don't know if this the best way but to fix that I am reimplementing resizeEvent and calling adjustSize to force the sizeHint recalculation.
With those two reimplemented methods MyCustomLabel shows with the right size. I placed this custom widget in a QHBoxLayout with a few other standard widgets. The problem is the other widgets in the layout don't respect the new size of my MyCustomLabel when the user resizes the window. What I end up with is the other widgets in the layout either overlapping or being placed too far from MyCustomLabel. I kind of get it, I am brute forcing my widget to a size and not letting the layout do the work. However I thought updating the sizeHint would inform the layout of MyCustomLabel's new size and adjust everything accordingly. How do I fix this layout problem or am I going about this widthForHeight problem all the wrong way?
Edit:
I tried #AlexanderVX suggestion of setting the SizePolicy to Minimum and while it does prevent the other widgets from overlapping it also locked MyCustomLabel to a fixed size. I need the widget to expand and shrink with the layout. I also tried Preferred, Expanding, MinimumExpanding policies just to see if they would do anything but with no luck.
from __future__ import division
from PySide import QtCore
from PySide import QtGui
import sys
class MyCustomLabel(QtGui.QLabel):
clicked = QtCore.Signal(int)
dblClicked = QtCore.Signal(int)
def __init__(self, leadSide='height', parent=None):
super(MyCustomLabel, self).__init__()
self.leadSide = leadSide
# sizePolicy = QtGui.QSizePolicy(QtGui.QSizePolicy.Preferred,
# QtGui.QSizePolicy.Preferred)
# sizePolicy = QtGui.QSizePolicy(QtGui.QSizePolicy.Expanding,
# QtGui.QSizePolicy.Expanding)
# sizePolicy = QtGui.QSizePolicy(QtGui.QSizePolicy.MinimumExpanding,
# QtGui.QSizePolicy.MinimumExpanding)
# sizePolicy = QtGui.QSizePolicy(QtGui.QSizePolicy.Minimum,
# QtGui.QSizePolicy.Minimum)
# self.setSizePolicy(sizePolicy)
def resizeEvent(self, event):
super(MyCustomLabel, self).resizeEvent(event)
self.adjustSize()
def sizeHint(self):
super(MyCustomLabel, self).sizeHint()
parentSize = self.parent().size().toTuple()
if self.leadSide.lower() == 'height':
new_size = QtCore.QSize(parentSize[1] * (16 / 9), parentSize[1]) * .9
if self.leadSide.lower() == 'width':
new_size = QtCore.QSize(parentSize[0], parentSize[0] / (16 / 9)) * .9
return new_size
class __Test__(QtGui.QWidget):
def __init__(self):
super(__Test__, self).__init__()
self.initUI()
def initUI(self):
customLabel = MyCustomLabel(leadSide='height')
# customLabel.setScaledContents(True)
customLabel.setStyleSheet('background-color: blue;'
'border:2px solid red;')
btn01 = QtGui.QPushButton('button')
btn01.setFixedHeight(80)
textEdit = QtGui.QTextEdit()
textEdit.setFixedSize(150, 150)
layout01 = QtGui.QHBoxLayout()
layout01.setContentsMargins(0,0,0,0)
layout01.setSpacing(0)
layout01.addWidget(customLabel)
layout01.addWidget(btn01)
layout01.addWidget(textEdit)
self.setLayout(layout01)
self.setGeometry(300, 300, 600, 300)
self.setWindowTitle('Testing')
self.show()
def main():
app = QtGui.QApplication(sys.argv)
ex = __Test__()
sys.exit(app.exec_())
if __name__ == '__main__':
main()

How to add a fixed header to a QScrollArea?

I currently have a QScrollArea defined by:
self.results_grid_scrollarea = QScrollArea()
self.results_grid_widget = QWidget()
self.results_grid_layout = QGridLayout()
self.results_grid_layout.setSizeConstraint(QLayout.SetMinAndMaxSize)
self.results_grid_widget.setLayout(self.results_grid_layout)
self.results_grid_scrollarea.setWidgetResizable(True)
self.results_grid_scrollarea.setWidget(self.results_grid_widget)
self.results_grid_scrollarea.setViewportMargins(0,20,0,0)
which sits quite happily nested within other layouts/widgets, resizes as expected, etc.
To provide headings for the grid columns, I'm using another QGridLayout positioned directly above the scroll area - this works... but looks a little odd, even when styled appropriately, especially when the on-demand (vertical) scrollbar appears or disappears as needed and the headers no longer line up correctly with the grid columns. It's an aesthetic thing I know... but I'm kinda picky ;)
Other widgets are added/removed to the self.results_grid_layout programatically elsewhere. The last line above I've just recently added as I thought it would be easy to use the created margin area, the docs for setViewportMargins state:
Sets margins around the scrolling area. This is useful for applications such as spreadsheets with "locked" rows and columns. The marginal space is is left blank; put widgets in the unused area.
But I cannot for the life of me work out how to actually achieve this, and either my GoogleFu has deserted me today, or there's little information/examples out there on how to actually achieve this.
My head is telling me I can assign just one widget, controlled by a layout (containing any number of other widgets) to the scrollarea - as I have done. If I add say a QHeaderview for example to row 0 of the gridlayout, it will just appear below the viewport's margin and scroll with the rest of the layout? Or am I missing something and just can't see the wood for the trees?
I'm just learning Python/Qt, so any help, pointers and/or examples (preferably with Python but not essential) would be appreciated!
Edit: Having followed the advice given so far (I think), I came up with the following little test program to try things out:
import sys
from PySide.QtCore import *
from PySide.QtGui import *
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.setMinimumSize(640, 480)
self.container_widget = QWidget()
self.container_layout = QVBoxLayout()
self.container_widget.setLayout(self.container_layout)
self.setCentralWidget(self.container_widget)
self.info_label = QLabel(
"Here you can see the problem.... I hope!\n"
"Once the window is resized everything behaves itself.")
self.info_label.setWordWrap(True)
self.headings_widget = QWidget()
self.headings_layout = QGridLayout()
self.headings_widget.setLayout(self.headings_layout)
self.headings_layout.setContentsMargins(1,1,0,0)
self.heading_label1 = QLabel("Column 1")
self.heading_label1.setContentsMargins(16,0,0,0)
self.heading_label2 = QLabel("Col 2")
self.heading_label2.setAlignment(Qt.AlignCenter)
self.heading_label2.setMaximumWidth(65)
self.heading_label3 = QLabel("Column 3")
self.heading_label3.setContentsMargins(8,0,0,0)
self.headings_layout.addWidget(self.heading_label1,0,0)
self.headings_layout.addWidget(self.heading_label2,0,1)
self.headings_layout.addWidget(self.heading_label3,0,2)
self.headings_widget.setStyleSheet(
"background: green; border-bottom: 1px solid black;" )
self.grid_scrollarea = QScrollArea()
self.grid_widget = QWidget()
self.grid_layout = QGridLayout()
self.grid_layout.setSizeConstraint(QLayout.SetMinAndMaxSize)
self.grid_widget.setLayout(self.grid_layout)
self.grid_scrollarea.setWidgetResizable(True)
self.grid_scrollarea.setWidget(self.grid_widget)
self.grid_scrollarea.setViewportMargins(0,30,0,0)
self.headings_widget.setParent(self.grid_scrollarea)
### Add some linedits to the scrollarea just to test
rows_to_add = 10
## Setting the above to a value greater than will fit in the initial
## window will cause the lineedits added below to display correctly,
## however - using the 10 above, the lineedits do not expand to fill
## the scrollarea's width until you resize the window horizontally.
## What's the best way to fix this odd initial behaviour?
for i in range(rows_to_add):
col1 = QLineEdit()
col2 = QLineEdit()
col2.setMaximumWidth(65)
col3 = QLineEdit()
row = self.grid_layout.rowCount()
self.grid_layout.addWidget(col1,row,0)
self.grid_layout.addWidget(col2,row,1)
self.grid_layout.addWidget(col3,row,2)
### Define Results group to hold the above sections
self.test_group = QGroupBox("Results")
self.test_layout = QVBoxLayout()
self.test_group.setLayout(self.test_layout)
self.test_layout.addWidget(self.info_label)
self.test_layout.addWidget(self.grid_scrollarea)
### Add everything to the main layout
self.container_layout.addWidget(self.test_group)
def resizeEvent(self, event):
scrollarea_vpsize = self.grid_scrollarea.viewport().size()
scrollarea_visible_size = self.grid_scrollarea.rect()
desired_width = scrollarea_vpsize.width()
desired_height = scrollarea_visible_size.height()
desired_height = desired_height - scrollarea_vpsize.height()
new_geom = QRect(0,0,desired_width+1,desired_height-1)
self.headings_widget.setGeometry(new_geom)
def main():
app = QApplication(sys.argv)
form = MainWindow()
form.show()
app.exec_()
if __name__ == '__main__':
main()
Is something along these lines the method to which you were pointing? Everything works as expected as is exactly what I was after, except for some odd initial behaviour before the window is resized by the user, once it is resized everything lines up and is fine.
I'm probably over-thinking again or at least overlooking something... any thoughts?

I had a similar problem and solved it a little differently. Instead of using one QScrollArea I use two and forward a movement of the lower scroll area to the top one. What the code below does is
It creates two QScrollArea widgets in a QVBoxLayout.
It disables the visibility of the scroll bars of the top QScrollArea and assigns it a fixed height.
Using the valueChanged signal of the horizontal scroll bar of the lower QScrollArea it is possible to "forward" the horizontal scroll bar value from the lower QScrollArea to the top one resulting a fixed header at the top of the window.
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
widget = QWidget()
self.setCentralWidget(widget)
vLayout = QVBoxLayout()
widget.setLayout(vLayout)
# TOP
scrollAreaTop = QScrollArea()
scrollAreaTop.setWidgetResizable(True)
scrollAreaTop.setFixedHeight(30)
scrollAreaTop.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
scrollAreaTop.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
scrollAreaTop.setWidget(QLabel(" ".join([str(i) for i in range(100)])))
# BOTTOM
scrollAreaBottom = QScrollArea()
scrollAreaBottom.setWidgetResizable(True)
scrollAreaBottom.setWidget(QLabel("\n".join([" ".join([str(i) for i in range(100)]) for _ in range(10)])))
scrollAreaBottom.horizontalScrollBar().valueChanged.connect(lambda value: scrollAreaTop.horizontalScrollBar().setValue(value))
vLayout.addWidget(scrollAreaTop)
vLayout.addWidget(scrollAreaBottom)

You may be over-thinking things slightly.
All you need to do is use the geometry of the scrollarea's viewport and the current margins to calculate the geometry of any widgets you want to place in the margins.
The geometry of these widgets would also need to be updated in the resizeEvent of the scrollarea.
If you look at the source code for QTableView, I think you'll find it uses this method to manage its header-views (or something very similar).
EDIT
To deal with the minor resizing problems in your test case, I would advise you to read the Coordinates section in the docs for QRect (in particular, the third paragraph onwards).
I was able to get more accurate resizing by rewriting your test case like this:
import sys
from PySide.QtCore import *
from PySide.QtGui import *
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.setMinimumSize(640, 480)
self.container_widget = QWidget()
self.container_layout = QVBoxLayout()
self.container_widget.setLayout(self.container_layout)
self.setCentralWidget(self.container_widget)
self.grid_scrollarea = ScrollArea(self)
self.test_group = QGroupBox("Results")
self.test_layout = QVBoxLayout()
self.test_group.setLayout(self.test_layout)
self.test_layout.addWidget(self.grid_scrollarea)
self.container_layout.addWidget(self.test_group)
class ScrollArea(QScrollArea):
def __init__(self, parent=None):
QScrollArea.__init__(self, parent)
self.grid_widget = QWidget()
self.grid_layout = QGridLayout()
self.grid_widget.setLayout(self.grid_layout)
self.setWidgetResizable(True)
self.setWidget(self.grid_widget)
# save the margin values
self.margins = QMargins(0, 30, 0, 0)
self.setViewportMargins(self.margins)
self.headings_widget = QWidget(self)
self.headings_layout = QGridLayout()
self.headings_widget.setLayout(self.headings_layout)
self.headings_layout.setContentsMargins(1,1,0,0)
self.heading_label1 = QLabel("Column 1")
self.heading_label1.setContentsMargins(16,0,0,0)
self.heading_label2 = QLabel("Col 2")
self.heading_label2.setAlignment(Qt.AlignCenter)
self.heading_label2.setMaximumWidth(65)
self.heading_label3 = QLabel("Column 3")
self.heading_label3.setContentsMargins(8,0,0,0)
self.headings_layout.addWidget(self.heading_label1,0,0)
self.headings_layout.addWidget(self.heading_label2,0,1)
self.headings_layout.addWidget(self.heading_label3,0,2)
self.headings_widget.setStyleSheet(
"background: green; border-bottom: 1px solid black;" )
rows_to_add = 10
for i in range(rows_to_add):
col1 = QLineEdit()
col2 = QLineEdit()
col2.setMaximumWidth(65)
col3 = QLineEdit()
row = self.grid_layout.rowCount()
self.grid_layout.addWidget(col1,row,0)
self.grid_layout.addWidget(col2,row,1)
self.grid_layout.addWidget(col3,row,2)
def resizeEvent(self, event):
rect = self.viewport().geometry()
self.headings_widget.setGeometry(
rect.x(), rect.y() - self.margins.top(),
rect.width() - 1, self.margins.top())
QScrollArea.resizeEvent(self, event)
if __name__ == '__main__':
app = QApplication(sys.argv)
form = MainWindow()
form.show()
sys.exit(app.exec_())

QGraphicsView not displaying QGraphicsItems

Using PyQt4.
My goal is to load in "parts" of a .png, assign them to QGraphicsItems, add them to the scene, and have the QGraphicsView display them. (Right now I don't care about their coordinates, all I care about is getting the darn thing to work).
Currently nothing is displayed. At first I thought it was a problem with items being added and QGraphicsView not updating, but after reading up a bit more on viewports, that didn't really make sense. So I tested adding the QGraphicsView items before even setting the view (so I know it wouldn't be an update problem) and it still displayed nothing. The path is definitely correct. Here is some code that shows what is going on...
Ignore spacing issues, layout got messed up when pasting
class MainWindow(QtGui.QMainWindow):
def __init__(self, parent = None):
QtGui.QMainWindow.__init__(self, parent)
self.setWindowTitle('NT State Editor')
winWidth = 1024
winHeight = 768
screen = QtGui.QDesktopWidget().availableGeometry()
screenCenterX = (screen.width() - winWidth) / 2
screenCenterY = (screen.height() - winHeight) / 2
self.setGeometry(screenCenterX, screenCenterY, winWidth, winHeight)
self.tileMap = tilemap.TileMap()
self.tileBar = tilebar.TileBar()
mapView = QtGui.QGraphicsView(self.tileMap)
tileBarView = QtGui.QGraphicsView(self.tileBar)
button = tilebar.LoadTilesButton()
QtCore.QObject.connect(button, QtCore.SIGNAL('selectedFile'),
self.tileBar.loadTiles)
hbox = QtGui.QHBoxLayout()
hbox.addWidget(mapView)
hbox.addWidget(self.tileBarView)
hbox.addWidget(button)
mainWidget = QtGui.QWidget()
mainWidget.setLayout(hbox)
self.setCentralWidget(mainWidget)
app = QtGui.QApplication(sys.argv)
mainWindow = MainWindow()
mainWindow.show()
sys.exit(app.exec_())
--
class Tile(QtGui.QGraphicsPixmapItem):
def __init__(self, parent = None):
QtGui.QGraphicsPixmapItem(self, parent)
self.idAttr = -1
class TileBar(QtGui.QGraphicsScene):
def __init__(self, parent = None):
QtGui.QGraphicsScene.__init__(self, parent)
def loadTiles(self, filename):
tree = ElementTree()
tree.parse(filename)
root = tree.getroot()
sheets = root.findall('sheet')
for sheet in sheets:
sheetPath = sheet.get('path')
sheetImg = QtGui.QImage(sheetPath)
strips = sheet.findall('strip')
for strip in strips:
tile = Tile()
tile.idAttr = strip.get('id')
clip = strip.find('clip')
x = clip.get('x')
y = clip.get('y')
width = clip.get('width')
height = clip.get('height')
subImg = sheetImg.copy(int(x), int(y), int(width), int(height))
pixmap = QtGui.QPixmap.fromImage(subImg)
tile.setPixmap(pixmap)
self.addItem(tile)
I tried some stuff with connecting the TileBar's 'changed()' signal with various 'view' functions, but none of them worked. I've had a bit of trouble finding good examples of ways to use the Graphics View Framework, (most are very very small scale) so let me know if I'm doing it completely wrong.
Any help is appreciated. Thanks.

It's quite hard to tell what's wrong with your code as it's not complete and missing some parts to get it compiled. Though there are couple of places which could potentially cause the problem:
Your Title class constructor; I believe you should be calling the base class constructor there by executing: QtGui.QGraphicsPixmapItem.__init__(self, parent).
Looks like your graphic scene objects are getting constructed in the button's onclick signal. There could be problems with your signal connecting to the proper slot, you should see warnings in the output if there are such problems in your widget.
It looks like you're loading images file names from the xml file, it's quite hard to check if the logic over there is straight but potentially you could have a problem over there too.
Below is simplified version of your code which loads ab image into the Title and adds it to the graphic scene:
import sys
from PyQt4 import QtGui, QtCore
class Tile(QtGui.QGraphicsPixmapItem):
def __init__(self, parent=None):
QtGui.QGraphicsPixmapItem.__init__(self, parent)
self.idAttr = -1
class TileBar(QtGui.QGraphicsScene):
def __init__(self, parent=None):
QtGui.QGraphicsScene.__init__(self, parent)
#def loadTiles(self, filename):
def loadTiles(self):
sheetImg = QtGui.QImage("put_your_file_name_here.png")
pixmap = QtGui.QPixmap.fromImage(sheetImg)
tile = Tile()
tile.setPixmap(pixmap)
self.addItem(tile)
# skipping your ElementTree parsing logic here
class MainWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QMainWindow.__init__(self, parent)
self.setWindowTitle('NT State Editor')
winWidth = 1024
winHeight = 768
screen = QtGui.QDesktopWidget().availableGeometry()
screenCenterX = (screen.width() - winWidth) / 2
screenCenterY = (screen.height() - winHeight) / 2
self.setGeometry(screenCenterX, screenCenterY, winWidth, winHeight)
#self.tileMap = Tiletilebar.Map()
self.tileBar = TileBar()
#mapView = QtGui.QGraphicsView(self.tileMap)
self.tileBarView = QtGui.QGraphicsView(self.tileBar)
#button = self.tilebar.LoadTilesButton()
button = QtGui.QPushButton()
QtCore.QObject.connect(button, QtCore.SIGNAL("clicked()"),
self.tileBar.loadTiles)
#self.tileBar.loadTiles('some_file_name')
hbox = QtGui.QHBoxLayout()
#hbox.addWidget(mapView)
hbox.addWidget(self.tileBarView)
hbox.addWidget(button)
mainWidget = QtGui.QWidget()
mainWidget.setLayout(hbox)
self.setCentralWidget(mainWidget)
app = QtGui.QApplication([])
exm = MainWindow()
exm.show()
app.exec_()
hope this helps, regards