Qt trigger resize event Mouse move events will occur only when a mouse button is pressed down, unless mouse tracking has been enabled with setMouseTracking(). Example 1: Handling Resize Event for a Custom Widget. I would like to generate the event by hand, or make it happen somehow so it positions the widgets correctly at the beginning. Qt docs suggests that every event posted with postEvent() that have accept() and ignore() methods can be propagated (meaning each QEvent subclass). For example, you might want to: Dec 17, 2012 · You can override the void QWidget::resizeEvent(QResizeEvent *event) and send a signal out of it: @ void MyMainWindow::resizeEvent (QResizeEvent *event) {// My signal emit mySizeChanged(event->size());} @ Each class subclasses QEvent and adds event-specific functions. See also addDockWidget(), splitDockWidget(), and Qt::DockWidgetArea. From the Jan 21, 2012 · This is a couple of years too late, but I was working on a transparent overlay widget that would completely cover the parent. But when you finish painting the Paint event of Qt happen so my drawings were obscured. In my case, I have a QFrame which is the parent of a QTextEdit. I have tried various events to try and trigger an adjustment to that TreeView but to no avail. The result is that, after that, all mouse move events are intercepted by the system until the button is released. Aug 14, 2018 · Is it by design that exiting the application with QApplication::quit() does not trigger closeEvent() of the main window? I was under the impression that qApp->quit() is the right way to exit the app, and the right slot to connect the "File -> Exit" menu action to. It seems that the QGraphicsView is getting events it shouldn't be, as a guess, try returning true just for QEvent::Resize and see if that makes a difference. If it does then I would put a breakpoint there to see where the resize events are coming from. resizeEvent(event) QtCore. Therefore you create 50 labels with the same image. Dec 31, 2015 · Thank all. If dockwidget has not been added to the main window, this function returns Qt::NoDockWidgetArea. Member Function . Such changes can be programmatic, user interaction or propagated from your operating system. In general, events come from the underlying window system ( spontaneous () returns true ), but it is also possible to manually send events using QCoreApplication Mar 6, 2021 · I would like to perform an action after I resize a QMainWindow (dragging the mouseafter cloicking the border or a cornerpoint. Nov 22, 2019 · After calling show(), a QEvent. [signal] void QMainWindow:: iconSizeChanged (const QSize &iconSize) May 2, 2013 · I am trying to propagate custom Qt event from child widgets to a top parent widget in order to trigger some action based on event type instead of linking signals. The widgets are in a vertical layout. Jul 16, 2022 · A resize event is posted whenever the size of a widget changes. You can override resizeEvent() in your own custom widgets to perform custom actions when the widget's size changes. It is not safe to modify or delete the event after it has been posted. h. But for some bizarre reason, when I apply this logic on a QToolButton (for showing some custom text popup on hovering over it), the button becomes invisible, although hovering over where it is supposed to be reveals the popup all right, and even the cursor becomes pointer as expected, given I set it like that for the button! Jun 19, 2019 · When undocking I resize the main window to be the size it would have been without the DockWindow but in doing so the right two columns disappear out of view. Jul 5, 2019 · void CurveDialog::resizeEvent(QResizeEvent *event) { mChartView->resize(ui->widget->size()); } This works, and the chart gets resizedbut the problem is it is terribly slow! because it will resize for all the steps that user drags the window corner to resize it! How can I do the resize only when there resize is done? May 15, 2011 · The next time Qt’s main event loop runs, it dispatches all posted events, with some optimization. Dec 17, 2012 · But the main window doesn´t emit the resize at the beginning of the app. Jan 14, 2012 · I've figured out how to trigger an event when the window changes, but this happens when I'm reading window information from the database, and I want to write to the database when the window is reduced, so, I would like to trigger my event based on clicking the reduce button as opposed to just any time the window changes. . onresize to control the time after Nov 12, 2024 · I don't think you can do this with standard Qt mechanics as what you describe differs from what is considered the default behaviour (resize any application - the font size usually stays the same). "During resize" I mean time when user has mouse pressed down on window border and moving the window. A way I have in mind is to remove (again) the windows control, substituting with a custom piece on the interface, or = probably most correct = manage the resize event in the c++ code and communicate this to the qml sources. So this is not really an option. By default, events are dispatched to event handlers like timerEvent() and QWidget::mouseMoveEvent(). I am trying resize it with resize Event but it exists (probably some errors). Lots of other posts are not explicit enough, e. necessary (and Qt takes good care to do so), so be sure that you are not implementing something in the wrong way. It will catch both kinds of resize event. g "use sizePolicy" or "use frameGeometry" or "use geometry" or "use sizeHint". May 2, 2025 · Only handlers registered on the window object will receive resize events. Resize events are sent to widgets that have been resized. If the resize event is triggered too many times for your application, see Optimizing window. This doesn't immediately trigger the paint event, but rather schedules it to be processed later. In the order, here is what is happening: Dec 4, 2009 · I have a QButton with an associated QMenu. I have a custumWidget which displays 3 QLineEdits. g. Aug 15, 2018 · If you want the image to have a maximum size but it should resize and get smaller if the window gets smaller you can use the following: pic. Create a new subclass of QGraphicsView, and handle the resize event there. Mar 22, 2011 · What I need is possible that is a way to intercept the window resize event. QMouseEvent supports mouse button presses, double-clicks, moves, and other related operations. Over 90 percent of questions asked here gets answered. 7k次，点赞18次，收藏15次。QResizeEvent是Qt提供的一个功能强大且灵活的窗口或控件大小变化事件处理类，通过本篇文章的学习，你应该对QResizeEvent有了全面的理解，能够在自己的项目中正确使用它。 Mar 24, 2022 · By default, QSizeGrip interfaces with the OS for the actual resizing as soon as it's activated (by pressing the left mouse button on it). QEvent *event: This parameter represents the event object that has occurred. installEventFilter() allows an object to intercept events destined for another object. do the font metrics for all the labels this leads to some oscillating of the widgets since they trigger each others resize events and keep going forever. Jan 23, 2020 · Probably I didn't explain myself enough clearly. Feb 21, 2007 · , we can handle the native Window events before they become QT- events. Qt Centre is a community site devoted to programming in C++ using the Qt framework. I want the frame to resize depending on this resolution, which also means that the buttons and window have to move/resize accordingly. When a resize event is created, it's done using this system anyway so it conforms to what's happening under the hood. The QGraphicsSceneResizeEvent class provides events for widget resizing in the graphics view framework. The event object (Event) encapsulates the state changes in the event source. The event target is the object that wants to be notified. Member Function Documentation QResizeEvent:: QResizeEvent (const QSize &size, const QSize &oldSize) Constructs a resize event with the new and old widget sizes, size and oldSize respectively. Apr 26, 2025 · Qt Widget Repainting with update() 2025-04-26. If you must When the Qt runtime is automatically called the resize function event or other window control size changes generates a Resize event. 使得Qt界面的控件随窗口的变化而变化 1. The same applies to paint events: update() calls postEvent(), which eliminates flickering and increases speed by avoiding multiple repaints. Jun 4, 2013 · Additionally you override QGraphicsView::drawBackground() which is virtual and gets called by Qt on resize of the viewport. size – PySide6. Some classes support more than one actual event type. Since I'm using an HID class device, there is no way to set an event to happen without a wait loop. the problem is not blocking/unblocking the signal - or when connecting the signal - but having an event which tells me WHEN doing it. I. Jun 22, 2008 · Welcome to Qt Centre. Dec 29, 2018 · When the QTableView is resized I want the entire table to resize its row heights, for each row. 1. h", you get the struct MSG wich gives you the information of the event. I want the video player to stop playing the video if I'm resizing the GUI. As far as what I know about layouts when the MainWindow is scaled down to say 1280x720 the child widget will not scale down proportionally because the MainWindow will still be large enough to accommodate it so it will only shift in position. Jan 28, 2018 · "propagate" I meant to trigger resize event in all the subwindows. One of the parts of my GUI is a video player. Maurizio Hello, When building PyQt application, sometimes I want to manually trigger the resize event, so as to fit the widgets, how can I do that? Jan 29, 2021 · Hi, When you hover the button, you are not inside QMainWindow anymore for that mouse related event. I Oct 28, 2018 · If I trigger the resize event again after initialization by dragging the screen around it gives me the correct width, but it shouldn't require that. ) Straightforward connecting a slot to a resizeEvent is not what I need, as while resizing the QMainWindow many of these events are emitted. Parameters. QtCore. Jan 23, 2020 · Thanks for the hint - I used the EventFilter. resize) but resized is not a builtin May 25, 2012 · If the widget has a one of Qt's layouts, this is already taken care of. Sep 27, 2023 · Hello, I ran into a problem that resizeEvent is triggered when I change the pixmap of QLabel in it (resizeEvent), which is a sub-widget of QWidget in my program. It contains information about the Aug 13, 2021 · 是一个Qt资源文件的路径。你需要将你的图片添加到Qt资源文件中，并在代码中通过资源路径来引用它。如果你不是使用Qt资源文件，你可以直接加载文件系统中的图片，比如使用。以下是一个简单的例子，展示如何在自定义的QWidget子类中重写。 Aug 26, 2020 · The problem in my case is, that if i e. See also QWidget::resize(), QWidget::setGeometry() Definition at line 546 of file qevent. The event handler QWidget::resizeEvent () receives resize events. Therefore, I have to handle all the move/resize events myself. The obvious approach would be to just emit a signal from the main window's resizeEvent and connect it to all the widgets which need it, but there will be lots of such widgets, so I would like to avoid this if possible. QTimer. QListWidgetItem* item = new QListWidgetItem(); ui->listWidget->insertItem(index, item); ui->listWidget->setItemWidget(item, customWidget); Apr 12, 2017 · This is a very good answer. For example, if there are several resize events, they are compressed into one. Scheduling the paint event The function marks the widget as needing a repaint. There are two kinds of show events: show events caused by the window system (spontaneous), and internal show events. You can use it for way more then just window resizing ;) for example to debounce a submit button by passing a higher timeout parameter. Apr 26, 2025 · It acts as a gateway for all events that occur within a widget, such as mouse clicks, key presses, paint events, resize events, and more. QResizeEvent. I am sure all of them may be right, but an example on how Oct 18, 2023 · In the event model, there are three participants: event source; event object; event target; The event source is the object whose state changes. QGraphicsSceneResizeEvent Class | Qt Widgets | Qt 6. setMaximumWidth(250) pic. How do i do it?. Jan 16, 2013 · Using Qt I create a QMainWindow and want to call a function AFTER the windows is shown. But in theory that should be much simpler than your mouse move approach, even if that is a little dirty too because it may use an "unnecessary" resize. The latter ones vary depending on your OS type. Internal show events are delivered just Dec 15, 2021 · Signals (and slots) allow you to connect disparate parts of your application together, making changes in one component trigger behavior in another. In general, events come from the underlying window system ( spontaneous() returns true), but it is also possible to manually send events using sendEvent() and postEvent() ( spontaneous() returns false). This resize triggers a child event within the layout (QHBoxLayout in this case). Processing the paint event At Jun 26, 2016 · This is okay. 9. QSize. Events are objects in your Qt C++ application, and they are indeed represented by the QEvent class. Apr 2, 2025 · Hi there. Aug 3, 2024 · 主要是窗口resize调用或者其他导致窗口事件大小发生变化产生。如果你想拖动主窗口的时候，能够让窗口中的组件随着窗口也能缩放的话，需要重写resizeEvent，原因在于，在构造之后，子窗口的大小就是固定的。 This is a reusable abstraction, so you don't have to handcode timeouts or keep track of global timeoutID's yourself. This virtual function receives events to an object and should return true if the event e was recognized and processed. with the way you already mentioned) Feb 10, 2009 · Hi, I have a Dialog that contain one Widget and the tipical OK_Cancel buttons. Thanks. Adding the QWidget to the QLayout does not change the size of W. Aug 28, 2012 · Inside this widget I have the QWebView, and when the parent QWidget on the QWebView resizes, I want to handle with the event "onResize", on any other similar event. Apr 12, 2018 · As you can see I create two widgets and when I resize widget1 or widget2 I send a message in stderr to see if the resize is detected and when a resize is done in widget1, I post the event in widget2 : void Widget1::resizeEvent(QResizeEvent *event) { qDebug() << "Widget 1 : resizeEvent"; QCoreApplication::postEvent(m_pOtherWidget, event); } Jun 14, 2013 · Or on the other hand I may want to draw something else on the screen during resize of window. This way I can modify the dimensions of the QDialog and correct the ratio before it goes to the Apr 6, 2021 · Here is a log of the event triggered to be a bit clearer. If you return false, this native event is passed back to Qt, which translates the event into a Qt event and sends it to the widget. Detailed Description. May 22, 2019 · I cannot create a functioning resize event for a custom QT class. While the resize event fires only for the window nowadays, you can get resize notifications for other elements using the ResizeObserver API. This object contains information about the old and new size of the widget, as well as the reason for the resize. Each subwindow is supposed to resize itself when it gets the event. Changed the example to always forward the event and in case the event is of type Resize, it emits a Signal, which is can be connected to a slot. If the widget does not have any child widgets, or uses manual layout, you can change the behavior of the widget using any or all of the following mechanisms: Oct 13, 2011 · "Installing an event filter on QCoreApplication::instance(). Oct 28, 2018 · Hi, I'd add an event filter for the QTableWidget's resize event and trigger that code there so you ensure that you are acting directly on the concerned widget. Reported Jun 5, 2019 · I used: setFixedSize(size()); to stop the window from resizing, but the resize arrows still appear when the mouse is over the border of the window. After include "windows. The QWidget::event() function is the central hub for handling events in Qt widgets. I don´t know the size of the window or anything else, so the Event i emit i don´t know what should be there. Resize events are sent to widgets that have been resized. there's nothing which assures me that from that moment no resize will be called again by the system, something that tells me "ok everything has been created, resized and showed. \inmodule QtGui. Constructs a resize event with the new and old Dec 25, 2024 · Moving a window between places on the desktop, whether on the same screen or not, does not change the size of the widget in pixels. If you to handle everything through your main window, you should check event filtering. Feb 11, 2007 · Welcome to Qt Centre. This is because SDL_PumpEvents (which is called directly or indirectly by sdl) will not return until resizing is done, effectively blocking your thread. When I run code it creates nice board but after resize it become looks ugly. The event contains a region() that needs to be updated, and a rect() that is the bounding rectangle of that region. setMaximumHeight(250) Share Jul 16, 2022 · A resize event is posted whenever the size of a widget changes. Layout Conflicts: Solution Use layouts whenever possible to manage the arrangement of child widgets. Dec 24, 2011 · Welcome to Qt Centre. I searched for any method to detect changing window size. The code above does not trigger it. However, there's one visual hint I don't know how to trigger, it's when the user drag the top of the window to the top of screen to maximize it. This is the generated code : from PyQt5 import QtCore, QtGui, QtWid Dec 17, 2012 · But the main window doesn´t emit the resize at the beginning of the app. As an experiment, you could replace your custom QLabel with a custom widget derived directly from QWidget and see what happens there. The thing is, as stated in the qt documentation, you cannot block the main thread, so, the best way I found to handle it was spinning a new daemon thread to run the event code without hanging the frontend. So far we've created a window and added a simple push button widget to it, but the button doesn't do anything. Now i can fix it by call function update draw before 50ms. 目的. oldSize ¶ Return type:. Although we don't see the internal logic of childEvent(), the layout automatically recalculates the positions and sizes of both buttons to accommodate the resized button1. Jul 18, 2022 · If you are using a single thread, setting up an event watcher using SDL_AddEventWatch is not enough. If you are looking for information about Qt related issue — register and post your question. You can not do what you want without subclassing, but you can restrict the subclassing to an instance as @reclosedev suggests, meaning that you don't have to actually create a subclass. I just want to trigger it when the MdiArea is resized – As I stated in my question, I didn't want to use events because it's a whole lot of unnecessary work to accomplish something extremely simply. I want the dialog to be resized automatically when I resize the Widget . This is ok IMHO since it's the desired behavior in most cases and can easily prevented for the special cases (e. size of the dialog is (which is taking some time as it's scaling, loading and setting the palette), then after a resize event occur for that said Dialog I execute the code snipped above. const QSize &QResizeEvent:: oldSize () const Returns the old size of the widget. Mar 13, 2018 · I use Qt/C++ and my main window is a frameless window. I also would need to know when resize is finished - mousebutton is released. You see this all the time. If you tell us what you're needing it for, we could help you with that. Also, the 'event' that needs to take place for the program to continue, is a USB event. Jul 25, 2017 · A recommendation before starting my answer, do not modify the class that generates Qt Designer, in your case by the name I think you used the template MainWindow, in the following code I added a bit of code that you have removed, what you must do is Create a new class that implements the generated view: Oct 15, 2009 · One approach you could take is to always paint the pixmap, but remember to recreate the pixmap "soon" if the window size has changed. The main point is this: I have an application that has a table which contains a lot of images (~a few hundereds) and when you perform a resizeEvent, the GUI lags a bit. resizeRowsToContents) and my override of resizeRowsToContents looked like this: Mar 29, 2017 · Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand I create a simple UI with Qt Designer and convert it to Python codes. Jan 6, 2016 · Googling the question found a lot of posts on how to use resize to an arbitrary size, and call to resize(int) works fine, but this is not quite what I am asking . Nov 1, 2019 · I want to do board with square widgets. PySide2. Is there a better way to disable window resizin Feb 3, 2023 · I am guessing that the layout is calling QWidget::resize() directly on your label, and that triggers a repaint of the widget. Cause If you modify the dialog's size within the resizeEvent() function, it can trigger another resize event, leading to an infinite loop. Apr 26, 2025 · When resizeEvent() is called, it is passed a QResizeEvent object as an argument. It's possible to make that?! 1 Reply Last reply The function can be reimplemented in subclasses to customize event handling and add additional event types; QWidget::event() is a notable example. Jul 3, 2011 · What is happening is that in the frame to the right, I am playing a video clip that can be of various resolutions. 要将Matlab Command Window嵌入到一个QDialog中，使得这个窗口控件随着窗口大小的改变而改变。这就要重写resizeEvent(QResizeEvent *event)函数。 Mar 16, 2025 · Instead, use timers or deferred calls to update the size after the current event has finished. When a toolbar button is clicked, a child widget (a game) is shown, overlayed on the main content area. I'm not sure if this cascades through the subwidgets Aug 23, 2020 · The problem was that I was handling the resize of the main window, and not the graphics view. QtGui. This way I can modify the dimensions of the QDialog and correct the ratio before it goes to the When the "Button 1" is clicked in the onButtonClicked slot, we resize button1. io Sep 5, 2021 · @eyllanesc said in Parent and Child Handling of Events: @D-Drum The documentation for that method says:. resized. Jul 7, 2024 · 文章浏览阅读2. arg__1 – PySide6. This happens event based, meaning if you do a fast resize you will get less paint events than doing it slow. Feb 1, 2020 · 視窗縮放時會觸發 resizeEvent ，而視窗關閉時會觸發 closeEvent 因此有物件要在視窗縮放或關閉時操作就寫入這些function裡. I wanted to check that I've correctly identified a dead end in my development. Log In. Code below is triggered in resizeEvent reimplemented in VideoTableView. Make sure undoView was initialized prior to this first resize event. Spontaneous (QEvent::spontaneous()) show events are sent just after the window system shows the window; they are also sent when a top-level window is redisplayed after being iconified. W owns a QLayout which owns QWidget. Such an event filter is able to process all events for all widgets, so it's just as powerful as reimplementing notify(); furthermore, it's possible to have more than one application-global event filter. Constructs a resize event with the new and old widget sizes, size and oldSize respectively. Feb 17, 2022 · @musicmante What about a situation where the child widget of a size for example 500x500 is within a MainWindow 1920x1080. Think, that will do the job :> Jul 14, 2014 · void MyView::resizeEvent(QResizeEvent *event) { fitInView(0, 0, 500, 500,Qt::KeepAspectRatio); QGraphicsView::resizeEvent(event); } This way the view will always display the whole scene. The event I want to handle is the 'on sizing' and the message is WM_SIZING. Apr 12, 2014 · Even if that function is called after the window has been resized you can set the size programatically and that will trigger another resize so you need to be careful and check the values. event() (which is a virtual itself); if event() is not overwritten, the base class implementation is called, which will look up for the class resizeEvent function and call it with the event as argument. Apr 6, 2021 · Here is a log of the event triggered to be a bit clearer. In the below example, we define a custom widget class that inherits from QWidget. Event source object delegates the task of May 3, 2020 · In my code I create a new QWidget: QWidget* pobjWin = new QWidget(); I get a pointer to a window: QWindow* pobjWindow = pobjWin = pobjWn->windowHand Qt’s main event loop ( exec()) fetches native window system events from the event queue, translates them into QEvents, and sends the translated events to QObject s. I found there is a slot QTableView::columnResized(), but I don't know, what event/signal triggers itd. Qt's main event loop (QCoreApplication::exec()) fetches native window system events from the event queue, translates them into QEvents, and sends the translated events to QObjects. [override virtual protected] bool QMainWindow:: event (QEvent *event) Reimplements: QWidget::event(QEvent *event). if the window size is changed and the graphicsView is resized, The scene gets scaled and you can see everything appropriately. Dec 3, 2013 · a resize event always also implies a trigger of a paint event thus you get it. The QMenu contains a single QWidgetAction with an associated widget. singleShot(0, self. 1. For example, QResizeEvent adds size () and oldSize () to enable widgets to discover how their dimensions have been changed. resizeEvent(QResizeEvent *event) is Called The Qt framework automatically calls the resizeEvent() function of your QComboBox object. Qt automatically grabs the mouse when a mouse button is pressed inside a widget; the widget will continue to receive mouse events until the last mouse button is released. connect(self. Apr 15, 2020 · In my QDialog constructor (which is triggered when a button is pressed) I set the backdrop image to what the . For example, if you place a child widget in a parent and the parent is too small, the child widget will be clipped. 1 Reply Last reply 0 Jan 8, 2019 · Qt窗口大小、位置及其大小改变引起的事件QResizeEvent. Currently QWidget::resize() event is fired wheneven mouse is moved even a Jan 24, 2018 · I'm using python3 and pyqt4 and I want some code to run every time my QMainWindow is resized. Feb 10, 2009 · Hi, I have a Dialog that contain one Widget and the tipical OK_Cancel buttons. In your reimplementation of this function, if you want to stop the event being handled by Qt, return true and set result. window. Nov 20, 2013 · It is like my event filter is filtering touch events out, or the TouchEvents can't go through layers, because if i remove all GUI(only have mainwindow left) i do receive the touch inputs i want, and when I change centralwidget, and add a new ui element / widget i can't receive the touch inputs. See also QWidget::resize () and QWidget::setGeometry (). If you want to drag the main window (or change the size), you can let the components in the window can be scared as the window, you need to rewrite the resizeEvent because the size of the sub-window is fixed after Qt; QTBUG-68500; maximized windows does not trigger resize event. I would like something like this self. Global event filters even see mouse events for disabled widgets. The Widget have to display an image and I want to resize it to a proportional size forcing the dialog to resize. Jan 18, 2011 · An event in Qt is an object which represents something interesting that happened; the main difference between an event and a signal is that events are targeted to a specific object in our application (which decides what to do with that event), while signals are emitted “in the wild”. Jan 19, 2016 · I would recommend that if you want to trigger a resize event, you do it using the postEvent mechanism. The QResizeEvent class contains event parameters for resize events. “Pyqt5 Parameters:. So, if you resize your window by 100 pixels, there is a good chance that the window receives 50 ( I'm just estimating here, could be less, could be more ) resize events. e. My override of resizeEvent is like this: def resizeEvent(self, event): super(). Detailed Description¶. 0 Back to Qt. Apr 12, 2019 · Different Methods to Handle Events in Qt; Reimplementing QObject::event() Event Filters on QObject; Installing Event Filter on QApplication; Subclassing QApplication and implementing notify() Sending your own events; Summary; What are Events. You can trigger behaviors in response to user input, such as button presses or text input, or events in your own code. It generates Events. Apr 16, 2015 · @Bremenpl Does it crash when you attempt to resize manually or as soon as you execute the application ? Because resize event will be fired at application startup too. resizeEvent（QResizeEvent *event）作为QT的事件函数在窗口控件大小获取方面具有借鉴作用。官方文档说明如下： void QWidget::resizeEvent(QResizeEvent *event) This event handler can be reimplemented in a subclass to receive widget resize events which are passed in the event parameter. This is why it works on resizing and not when calling your update() on the QGraphicsView widget. It overrides the resizeEvent() method to print the size of the widget whenever it's resized. Nov 26, 2019 · In my case, my application is running on python (PyQt5 + QML), the event comes from QML code, and is handled in a slot (nothing new here). Probably I didn't explain myself enough clearly. oldSize – PySide6. Apr 26, 2025 · Resize Occurs The QComboBox's size changes due to user interaction (dragging a window border) or programmatic changes (calling resize() or the layout manager adjusting it). When I call the function in the constructor the function (a dialog actually) get's called before the window is Sep 10, 2018 · I suspect a problem in the code, but I don't know where to start in this case. Sep 14, 2006 · The event must be allocated on the heap since the post event queue will take ownership of the event and delete it once it has been posted. That is where the window resize comes in. Now I want to change the content of the widget contained in the menu at some point, and have the QMenu resize itself when shown so that the QMenu is the appropriate size for the content in the widget. These customWidgets are stored inside a QListWidget like this:. I would not expect a resize event unless the widget is actually resized. May 15, 2011 · Paint events are sent to widgets that need to update themselves, for instance when part of a widget is exposed because a covering widget was moved. Oct 17, 2010 · What I need, is to somehow intercept event or signal, when columns (not whole widget) in VideoTableView get resized. Returns the old size of the widget. The event handler QWidget::resizeEvent() receives resize events. and QGraphicsWidget::resize(). I'm using an API to draw. So, when the paintEvent comes in, if the size is different to current pixmap size, then paint the stored pixmap anyway, but then set (or reset) a QTimer to trigger a signal to a slot which will refresh the pixmap. You could probably override QWidget::render() or similar and use scale on the supplied QPainter. May 27, 2007 · But the resize events are posted very quickly. It is not guaranteed that the construction of a widget triggers a resize event. May 11, 2017 · However, the resize events of the children seem to trigger sooner than the resize event of the parent. The result parameter has meaning only on Windows. Resize is received by QWidget. May 15, 2011 · Constructs a resize event with the new and old widget sizes, size and oldSize respectively. etrczq qjbg itpsr mmoa xayjwn ise xdcfd cndi igqxku lhr