Widget dragging not working when hovering over the widget itself - python

I'm having an issue where I have implemented a dragging feature for widgets using eventFilter(), but it seems when I drag towards the right and my cursor hovers over the widget which in my case is a QPushButton it seems to stop tracking until I hover out of the widget
How would I fix this?
class widget1(QWidget):
def __init__(self):
super().__init__()
self.widget = QPushButton("button0", self)
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.createbutton = QPushButton('+', self)
self.createbutton.setGeometry(5, 5, 15, 15)
self.createbutton.clicked.connect(self.createWidget)
self.show()
def createWidget(self):
self.new_widget = widget1()
self.new_widget.setParent(self)
self.new_widget.show()
self.new_widget.installEventFilter(self)
def eventFilter(self, source, event):
if event.type() == QEvent.MouseMove:
MousePos = QPoint(event.pos())
if event.buttons() == Qt.LeftButton:
source.move(source.x() + MousePos.x(), source.y() + MousePos.y())
return super(MainWindow, self).eventFilter(source, event)
Basically I have a class with a widget in it called widget1() (This will be my custom widget in the future) I am then adding it dynamically to the window every time I press self.createbutton using .show() instead of using a layout, then it installs the event filter to it so that it can allow for dragging.

The event filter is receiving events for the widget1 instance but not for its child widgets (i.e. the QPushButton). A quick fix is to invoke QMouseEvent.ignore for the QPushButton's mouseMoveEvent so the mouse event will be propagated up to the parent widget and received in the event filter.
class widget1(QWidget):
def __init__(self):
super().__init__()
self.widget = QPushButton("button0", self)
self.widget.mouseMoveEvent = lambda event: event.ignore()

Related

How to dim background when using qmessagebox?

I want to set the background in dim mode, when a QMessagebox is popped up.
Currently, I have tried to use a simple QMesssagebox, but the background shows as normal display, when it pops up.
The image for 1st page is as follow
When go to next slide is pushed, it goes to next index as follow
When going back to 1st index, the back button is pushed which pops up the messagebox as follow
However, the mainwindow seems to have no effect on its focus.
Therefore, what would I need to do to make it dimmer than the focused messagebox.
How can I do this? Any suggestions?
EDIT
import sys
from PyQt5 import uic
from PyQt5.QtWidgets import QApplication, QMainWindow, QMessageBox
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.ui = uic.loadUi("message.ui",self)
self.notification = QMessageBox()
self.ui.next_slide.clicked.connect(self.second_index)
self.ui.go_back.clicked.connect(self.alert_msg)
self.show()
def home(self):
self.ui.stackedWidget.setCurrentIndex(0)
def second_index(self):
self.ui.stackedWidget.setCurrentIndex(1)
def alert_msg(self):
self.notification.setWindowTitle("Exiting")
self.notification.setText("Are you sure, you want to exit")
self.notification.setIcon(QMessageBox.Critical)
self.notification.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
self.back = self.notification.exec_()
if self.back == QMessageBox.Yes:
self.home()
else:
pass
if __name__ == "__main__":
app=QApplication(sys.argv)
mainwindow=MainWindow()
app.exec_()
You can create a custom widget that is a direct child of the window that has to be "dimmed", ensure that it always has the same size as that window, and just paint it with the selected color:
class Dimmer(QWidget):
def __init__(self, parent):
parent = parent.window()
super().__init__(parent)
parent.installEventFilter(self)
self.setAttribute(Qt.WA_DeleteOnClose)
self.adaptToParent()
self.show()
def adaptToParent(self):
self.setGeometry(self.parent().rect())
def eventFilter(self, obj, event):
if event.type() == event.Resize:
self.adaptToParent()
return super().eventFilter(obj, event)
def paintEvent(self, event):
qp = QPainter(self)
qp.fillRect(self.rect(), QColor(127, 127, 127, 127))
class MainWindow(QMainWindow):
# ...
def alert_msg(self):
dimmer = Dimmer(self)
# ...
self.back = self.notification.exec_()
dimmer.close()
Note that, unless you plan to reuse the "dim widget", it must be destroyed either by calling close() as done above (see the WA_DeleteOnClose flag) or using deleteLater(). Hiding it will not be enough.

Drawing Line from QLabel to QLabel in PyQt

I'm fairly new to PyQt
I'm trying to drawing a line from 1 QLabel to another.
My 2 QLabel are located on another QLabel which acts as an image in my GUI.
I've managed to track the mouse event and move the label around, but I cannot draw the line between them using QPainter.
Thank you in advance :)
This is my MouseTracking class
class MouseTracker(QtCore.QObject):
positionChanged = QtCore.pyqtSignal(QtCore.QPoint)
def __init__(self, widget):
super().__init__(widget)
self._widget = widget
self.widget.setMouseTracking(True)
self.widget.installEventFilter(self)
#property
def widget(self):
return self._widget
def eventFilter(self, o, e):
if e.type() == QtCore.QEvent.MouseMove:
self.positionChanged.emit(e.pos())
return super().eventFilter(o, e)
This is my DraggableLabel class:
class DraggableLabel(QLabel):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.LabelIsMoving = False
self.setStyleSheet("border-color: rgb(238, 0, 0); border-width : 2.0px; border-style:inset; background: transparent;")
self.origin = None
# self.setDragEnabled(True)
def mousePressEvent(self, event):
if not self.origin:
# update the origin point, we'll need that later
self.origin = self.pos()
if event.button() == Qt.LeftButton:
self.LabelIsMoving = True
self.mousePos = event.pos()
# print(event.pos())
def mouseMoveEvent(self, event):
if event.buttons() == Qt.LeftButton:
# move the box
self.move(self.pos() + event.pos() - self.mousePos)
# print(event.pos())
def mouseReleaseEvent(self, event):
if event.button() == Qt.LeftButton:
print(event.pos())
def paintEvent(self, event):
painter = QPainter()
painter.setBrush(Qt.red)
# painter.setPen(qRgb(200,0,0))
painter.drawLine(10, 10, 200, 200)
This is my custom class for the QTabwigdet (since I need to control and track the position of 2 QLabels whenever the user add/insert a new Tab)
class DynamicTab(QWidget):
def __init__(self):
super(DynamicTab, self).__init__()
# self.count = 0
self.setMouseTracking(True)
self.setAcceptDrops(True)
self.bool = True
self.layout = QVBoxLayout(self)
self.label = QLabel()
self.layout.addChildWidget(self.label)
self.icon1 = DraggableLabel(parent=self)
#pixmap for icon 1
pixmap = QPixmap('icon1.png')
# currentTab.setLayout(QVBoxLayout())
# currentTab.layout.setWidget(QRadioButton())
self.icon1.setPixmap(pixmap)
self.icon1.setScaledContents(True)
self.icon1.setFixedSize(20, 20)
self.icon2 = DraggableLabel(parent=self)
pixmap = QPixmap('icon1.png')
# currentTab.setLayout(QVBoxLayout())
# currentTab.layout.setWidget(QRadioButton())
self.icon2.setPixmap(pixmap)
self.icon2.setScaledContents(True)
self.icon2.setFixedSize(20, 20)
#self.label.move(event.x() - self.label_pos.x(), event.y() - self.label_pos.y())
MainWindow and main method:
class UI_MainWindow(QMainWindow):
def __init__(self):
super(UI_MainWindow, self).__init__()
self.setWindowTitle("QHBoxLayout")
self.PictureTab = QTabWidget
def __setupUI__(self):
# super(UI_MainWindow, self).__init__()
self.setWindowTitle("QHBoxLayout")
loadUi("IIML_test2.ui", self)
self.tabChanged(self.PictureTab)
# self.tabChanged(self.tabWidget)
self.changeTabText(self.PictureTab, index=0, TabText="Patient1")
self.Button_ImportNew.clicked.connect(lambda: self.insertTab(self.PictureTab))
# self.PictureTab.currentChanged.connect(lambda: self.tabChanged(QtabWidget=self.PictureTab))
# self.tabWidget.currentChanged.connect(lambda: self.tabChanged(QtabWidget=self.tabWidget))
def tabChanged(self, QtabWidget):
QtabWidget.currentChanged.connect(lambda : print("Tab was changed to ", QtabWidget.currentIndex()))
def changeTabText(self, QTabWidget, index, TabText):
QTabWidget.setTabText(index, TabText)
def insertTab(self, QtabWidget):
# QFileDialog.getOpenFileNames(self, 'Open File', '.')
QtabWidget.addTab(DynamicTab(), "New Tab")
# get number of active tab
count = QtabWidget.count()
# change the view to the last added tab
currentTab = QtabWidget.widget(count-1)
QtabWidget.setCurrentWidget(currentTab)
pixmap = QPixmap('cat.jpg')
#currentTab.setLayout(QVBoxLayout())
#currentTab.layout.setWidget(QRadioButton())
# currentTab.setImage("cat.jpg")
currentTab.label.setPixmap(pixmap)
currentTab.label.setScaledContents(True)
currentTab.label.setFixedSize(self.label.width(), self.label.height())
tracker = MouseTracker(currentTab.label)
tracker.positionChanged.connect(self.on_positionChanged)
self.label_position = QtWidgets.QLabel(currentTab.label, alignment=QtCore.Qt.AlignCenter)
self.label_position.setStyleSheet('background-color: white; border: 1px solid black')
currentTab.label.show()
# print(currentTab.label)
#QtCore.pyqtSlot(QtCore.QPoint)
def on_positionChanged(self, pos):
delta = QtCore.QPoint(30, -15)
self.label_position.show()
self.label_position.move(pos + delta)
self.label_position.setText("(%d, %d)" % (pos.x(), pos.y()))
self.label_position.adjustSize()
# def SetupUI(self, MainWindow):
#
# self.setLayout(self.MainLayout)
if __name__ == '__main__':
app = QApplication(sys.argv)
UI_MainWindow = UI_MainWindow()
UI_MainWindow.__setupUI__()
widget = QtWidgets.QStackedWidget()
widget.addWidget(UI_MainWindow)
widget.setFixedHeight(900)
widget.setFixedWidth(1173)
widget.show()
try:
sys.exit(app.exec_())
except:
print("Exiting")
My concept: I have a DynamicTab (QTabWidget) which acts as a picture opener (whenever the user press Import Now). The child of this Widget are 3 Qlabels: self.label is the picture it self and two other Qlabels are the icon1 and icon2 which I'm trying to interact/drag with (Draggable Label)
My Problem: I'm trying to track my mouse movement and custom the painter to paint accordingly. I'm trying that out by telling the painter class to paint whenever I grab the label and move it with my mouse (Hence, draggable). However, I can only track the mouse position inside the main QLabel (the main picture) whenever I'm not holding or clicking my left mouse.
Any help will be appreciated here.
Thank you guys.
Painting can only happen within the widget rectangle, so you cannot draw outside the boundaries of DraggableLabel.
The solution is to create a further custom widget that shares the same parent, and then draw the line that connects the center of the other two.
In the following example I install an event filter on the two draggable labels which will update the size of the custom widget based on them (so that its geometry will always include those two geometries) and call self.update() which schedules a repainting. Note that since the widget is created above the other two, it might capture mouse events that are intended for the others; to prevent that, the Qt.WA_TransparentForMouseEvents attribute must be set.
class Line(QWidget):
def __init__(self, obj1, obj2, parent):
super().__init__(parent)
self.obj1 = obj1
self.obj2 = obj2
self.obj1.installEventFilter(self)
self.obj2.installEventFilter(self)
self.setAttribute(Qt.WA_TransparentForMouseEvents)
def eventFilter(self, obj, event):
if event.type() in (event.Move, event.Resize):
rect = self.obj1.geometry() | self.obj2.geometry()
corner = rect.bottomRight()
self.resize(corner.x(), corner.y())
self.update()
return super().eventFilter(obj, event)
def paintEvent(self, event):
painter = QPainter(self)
painter.setRenderHint(painter.Antialiasing)
painter.setPen(QColor(200, 0, 0))
painter.drawLine(
self.obj1.geometry().center(),
self.obj2.geometry().center()
)
class DynamicTab(QWidget):
def __init__(self):
# ...
self.line = Line(self.icon1, self.icon2, self)
Notes:
to simplify things, I only use resize() (not setGeometry()), in this way the widget will always be placed on the top left corner of the parent and we can directly get the other widget's coordinates without any conversion;
the custom widget is placed above the other two because it is added after them; if you want to place it under them, use self.line.lower();
the painter must always be initialized with the paint device argument, either by using QPainter(obj) or painter.begin(obj), otherwise no painting will happen (and you'll get lots of errors in the output);
do not use layout.addChildWidget() (which is used internally by the layout), but the proper addWidget() function of the layout;
the stylesheet border syntax can be shortened with border: 2px inset rgb(238, 0, 0);;
the first lines of insertTab could be simpler: currentTab = DynamicTab() QtabWidget.addTab(currentTab, "New Tab");
currentTab.label.setFixedSize(self.label.size());
QMainWindow is generally intended as a top level widget, it's normally discouraged to add it to a QStackedWidget; note that if you did that because of a Youtube tutorial, that tutorial is known for suggesting terrible practices (like the final try/except block) which should not be followed;
only classes and constants should have capitalized names, not variables and functions which should always start with a lowercase letter;

QMenu (contextMenuEvent) not closing on click on action nor parent QWidget

I am trying to create a context menu (QMenu) for a right-click inside of PatternWidget(QWidget) with PySide6.
For this purpose I have overwritten contextMenuEvent as seen below.
For whatever reason, the context menu will NOT exit, when any of the actions in it or any space around it within PatternWidget is clicked, whether by left nor by right click.
The only way I can make the QMenu close is to click inside another widget or outside of the whole Application window.
I spent a long time on Google already and it seems that people usually have the opposite problem (keeping it open when clicking somewhere). I therefore think that something must be wrong in my code that prevents the default behavior to close the QMenu rather than me having to connect to some Signal and close it manually
I was also wondering if the Mouse Click event is not bubbling up until the QMenu but,the signals of the actions in the QMenu (Copy Row Up and Down) are firing as expected when clicked.
EDIT:
Removed QScrollArea
Added Code for PatternOverlay
class MainWindow(QMainWindow):
...
def __init_layout(self):
self.layout = QHBoxLayout()
self.layout.setContentsMargins(10, 10, 10, 10)
self.layout.setSpacing(1)
self.mainWidget = QWidget()
self.mainWidget.setLayout(self.layout)
self._scene = QtWidgets.QGraphicsScene(self)
self._view = QtWidgets.QGraphicsView(self._scene)
self._view.setStyleSheet("border: 0px; background-color: Gainsboro")
self.pattern_widget = PatternWidget()
self._scene.addWidget(self.pattern_widget)
self.layout.addWidget(self._view)
self.setCentralWidget(self.mainWidget)
class PatternOverlay(QWidget):
def __init__(self, parent):
super().__init__(parent=parent)
self.setAttribute(Qt.WA_NoSystemBackground)
self.setAttribute(Qt.WA_TransparentForMouseEvents)
self.rects = []
def paintEvent(self, _):
painter = QPainter(self)
painter.setPen(QPen(Qt.blue, 2, Qt.SolidLine))
for rect in self.rects:
painter.drawRect(rect)
painter.end()
self.rects.clear()
def addRect(self, rect):
self.rects.append(rect)
class PatternWidget(QWidget):
def __init__(self, cell_width, cell_height, stitches, rows):
super().__init__()
self.setSizePolicy(QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Fixed)
self.setMouseTracking(True)
# initialize overlay
self.__overlay = PatternOverlay(self)
self.__overlay.resize(self.size())
self.__overlay.show()
...
def contextMenuEvent(self, e):
copy_row_up_action = QAction("Copy Row Up", self)
copy_row_up_action.setStatusTip("Copy Row Up")
copy_row_up_action.triggered.connect(self.__handle_copy_row_up)
copy_row_down_action = QAction("Copy Row Down", self)
copy_row_down_action.setStatusTip("Copy Row Down")
copy_row_down_action.triggered.connect(self.__handle_copy_row_down)
context = QMenu(self)
context.addActions([copy_row_up_action, copy_row_down_action])
context.exec_(e.globalPos())

copy/select text in WhatsThis

Example:
class tab_1(QWidget):
def __init__(self):
super(tab_1, self).__init__()
self.initUI()
def initUI(self):
self.btn = QPushButton(self)
self.btn.setText("tab1")
self.btn.setWhatsThis(
"""''(parameter) self: ~tab
Sourcery Code Metrics
Complexity 0 ⭐
Size 108 🙂
Working Memory 4 ⭐
Quality Score 82 % ⭐
⟠ self: [tab] Docc"""
""
)
I use the setWhatsThis and try to copy/select the text of it, but
when I click the mouse
In WhatsThis area is Disappear!
Example
In general, the what's this behavior is to only handles clicks on hyperlinks (which normally launch the application help dialog), so if the user clicks it, it will automatically close anyway.
The only solution is to override the default behavior by mimicking what Qt normally does: install an event filter on the application whenever a top level window receives a EnterWhatsThisMode event type, and create a custom widget that is shown whenever it's appropriate.
Since this will cause to override all what's this cases, I'd suggest to also set the WA_CustomWhatsThis attribute for the widgets that will have selectable text, so that you can use the standard behavior for any other case.
The custom widget is actually a QLabel with the Popup window flag set, which will make the widget a top level window that also captures mouse events, and with the TextSelectableByMouse and LinksAccessibleByMouse text interaction flags set.
class SelectableWhatsThis(QtWidgets.QLabel):
def __init__(self, parent, pos):
super().__init__(parent.whatsThis(), parent, flags=QtCore.Qt.Popup)
self.setTextInteractionFlags(
QtCore.Qt.TextSelectableByMouse | QtCore.Qt.LinksAccessibleByMouse)
self.setBackgroundRole(QtGui.QPalette.ToolTipBase)
self.setForegroundRole(QtGui.QPalette.ToolTipText)
self.setAutoFillBackground(True)
self.setContentsMargins(12, 8, 12, 8)
self.move(pos)
self.show()
def mousePressEvent(self, event):
if event.pos() not in self.rect():
self.close()
else:
super().mousePressEvent(event)
def keyPressEvent(self, event):
self.close()
class WhatsThisHelper(QtCore.QObject):
installed = active = False
whatsThis = None
def __init__(self, parent):
super().__init__(parent)
if not self.installed:
# ensure that only one instance of WhatsThisHelper is installed
self.__class__.installed = True
QtWidgets.QApplication.instance().installEventFilter(self)
self.active = True
def eventFilter(self, obj, event):
if not obj.isWidgetType():
return False
if (event.type() == event.MouseButtonPress
and event.button() == QtCore.Qt.LeftButton
and obj.whatsThis() and
obj.testAttribute(QtCore.Qt.WA_CustomWhatsThis)):
self.whatsThis = SelectableWhatsThis(obj, event.globalPos())
QtWidgets.QApplication.restoreOverrideCursor()
return True
elif event.type() in (event.MouseButtonRelease, event.MouseButtonDblClick):
if self.whatsThis:
QtWidgets.QWhatsThis.leaveWhatsThisMode()
return True
elif event.type() == event.LeaveWhatsThisMode:
QtWidgets.QApplication.instance().removeEventFilter(self)
self.deleteLater()
return super().eventFilter(obj, event)
def __del__(self):
if self.active:
self.__class__.installed = False
class MainWindow(QtWidgets.QMainWindow):
# ...
def event(self, event):
if event.type() == event.EnterWhatsThisMode:
WhatsThisHelper(self)
return super().event(event)
Note that you need to override the event of all widgets that are going to be top level widgets (all QMainWindows, QDialogs, etc) and need to support this.

Hover Event for a QGraphicsItem (PyQt4)

I want some small text to pop up when I have my curser over a QGraphicsItem in my QGraphicsScene. I have a class that inherits from QGraphicsItem, and this represents my graphical items in the scene.
I tried using the QGraphicsItem.hoverEnterEvent and I also set the setAcceptHoverEvents(True), but I still can't enable that hover event. I also came across an event filter method but I'm not sure where to implement it.
Should I install the event filter in the QGraphicsItem class, or the scene? I tried both and I'm still not getting the desired result. I want to be able to hover over all the items in the scene.
UPDATE:
So I tried doing this but the hover event still isn't being detected.
class graphics_Object(QtGui.QGraphicsPixmapItem):
def __init__(self, parent=None):
super(graphics_Object, self).__init__(parent)
pixmap = QtGui.QPixmap("item.png")
self.graphics_pixItem = QtGui.QGraphicsPixmapItem(pixmap.scaled(40, 40, QtCore.Qt.KeepAspectRatio))
self.graphics_pixItem.setFlag(QtGui.QGraphicsPixmapItem.ItemIsSelectable)
self.graphics_pixItem.setFlag(QtGui.QGraphicsPixmapItem.ItemIsMovable)
self.graphics_pixItem.setAcceptHoverEvents(True)
def hoverEnterEvent(self, event):
print 'hello'
class graphicsScene(QtGui.QGraphicsScene):
def __init__(self, parent=None):
super(graphicsScene, self).__init__(parent)
def mousePressEvent(self, event):
self.graphics_item = graphics_Object()
def mouseReleaseEvent(self, event)
self.addItem(self.graphics_item.graphics_pixItem)
self.graphics_item.graphics_pixItem.setPos(event.scenePos())
class Form(QtGui.QMainWindow):
def __init__(self):
super(Form, self).__init__()
self.ui = uic.loadUi('form.ui')
self.scene = graphicsScene()
self.ui.view.setScene(self.scene)
self.setMouseTracking(True)
You are making another pixmapItem inside you graphics_Object class, graphics_Object is already a subclass of graphicsPixmapItem so I don't see a purpose for this.
Then you only add that nested pixmapItem to the scene and your hoverEnterEvent is on the graphics_Object which is never added to the scene. That is why you are not receiving hover events.
One of many solutions would be to just add your graphics object to the scene instead of the nested graphicsPixmapItem and use setPixmap() in the init of graphics_Object
class graphics_Object(QtGui.QGraphicsPixmapItem):
def __init__(self, parent=None):
super(graphics_Object, self).__init__(parent)
pixmap = QtGui.QPixmap("item.png")
self.setPixmap(pixmap.scaled(40, 40, QtCore.Qt.KeepAspectRatio))
self.setFlag(QtGui.QGraphicsPixmapItem.ItemIsSelectable)
self.setFlag(QtGui.QGraphicsPixmapItem.ItemIsMovable)
self.setAcceptHoverEvents(True)
def hoverEnterEvent(self, event):
print('hello')
class graphicsScene(QtGui.QGraphicsScene):
def __init__(self, parent=None):
super(graphicsScene, self).__init__(parent)
def mousePressEvent(self, event):
self.graphics_item = graphics_Object()
def mouseReleaseEvent(self, event):
print('adding to scene')
self.addItem(self.graphics_item)
self.graphics_item.setPos(event.scenePos())
When you inherit (subclass) from a pyqt class or any class in python, think of the new class as a "copy" of the inherited class. It will behave the exact same way as the base class until you overwrite a method, in this case, we override the "init" and "hoverEnterEvent" methods to do our custom stuff. Everything else about a QGraphicsPixmapItem stays the same

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