Qt eventfilter keypress first. XML Word Printable. If it's not too much trouble, could you please explain why eventfilter worked but not my earlier code? I'm new to Qt and the documentation doesn't always help me understand things. Key_Up: self. zip archive. virtual bool QObject:: eventFilter (QObject * watched, QEvent * event); 这个函数正如其名字显示的那样，是一个“事件过 好在 Qt 提供了另外一种机制来达到这一目的：事件过滤器。 QObject有一个eventFilter()函数，用于建立事件过滤器。这个函数的签名如下： 复制代码. (QObject::installEventFilter ()) In the event filter, add a clause to detect KeyPress Event Filtering For more fine-grained control, you can use event filters instead of overriding keyPressEvent (). call_sc() return super(). 7. 3 如何自己模拟发送事件消息 一、Qt中事件过滤器详解 我们先看下另外两个相关的方法，一个是给对象安装某个事件过滤器，一个是移除对 One more approach can be to override the eventFilter() function of the lineEdit like :- @bool eventFilter(QObject *target, QEvent *event);@ and in the implementation you can try 这个函数是QObject的一个函数，因此可以安装到任何QObject的子类，并不仅仅是UI组件。这个函数接收一个QObject对象，调用了这个函数安装事件过滤器的组件会调用filterObj定义的eventFilter()函数。例如，textField. The QCompleter is not a widget. cpp is a constant and compulsory project class, and the second. Qt プログラミングにおける QDialog::eventFilter() は、イベントフィルタリングの仕組みを利用して、ダイアログウィジェットに送られるイベントを事前に捕捉し、処理する機能です。これにより、イベントのデフォルト処理をカスタマイズしたり、新たなイベント処理を追加することができます。. Therefore I install an eventfilter on the QTreeView instance in the constructor of my mainwindow, as suggested in the docs: See the documentation of QKeyEvent:. I registerered eventFilter() for application: q Hi all, I'm having a problem using the eventfilter and the QEvent::KeyRelease event. What you can do is to additionally check for the event type QEvent::ShortcutOverride. The eventFilter function should receive any event, check if it's a key event, then check if it's the enter button. 3 如何自己模拟发送事件消息 一、Qt中事件过滤器详解 我们先看下另外两个相关的方法，一个是给对象安装某个事件过滤器，一个是移除对 When the window is hidden, I can't get KeyPress events, and the events are printed like this: print my event: QEvent(SockAct, oxbe971a9c, type = 50) That is, I expected to get KeyPress events, but all I can get are these Socket Activation events. The Editor retains focus. You can QKeyEvent is part of Event Classes. 1 Qt中事件是如何进行传递 1. I need to do some action when shortcut pressed in tableView. cpp). I tried using installEventFilter earlier but I was clear on how to use it so I went back to the regular keypress event which didn't work. Does anyone know how can I get KeyPress events when my MainWindow is hidden? I'm using Qt 4. Instead I registered shortcuts for the keyboard buttons I wanted to use: QShortcut *shortcutUp = new QShortcut(QKeySequence("Up"), this); QObject::connect(shortcutUp, SIGNAL(activated()), Implementation-wise this appears to be not so trivial: for one, the center widget does not always have focus and thus does not even receive keyPress/keyRelease-events. 3 如何自己模拟发送事件消息 一、Qt中事件过滤器详解 我们先看下另外两个相关的方法，一个是给对象安装某个事件过滤器，一个是移除对 qt事件过滤----eventFilter应用，文章目录qt事件过滤Demo示例程序--通过事件过滤实现文本框回车焦点下移qt事件过滤第一步：子控件注册过滤器ui->lineEdit->installEventFilter(this);ui->lineEdit_2->installEventFilter(this);ui->lineEdit_3->installEventFilter(this);第二步：添 イベントフィルタ(eventFilterメソッド) mousePressEventメソッドやkeyPressEventメソッド等; KeyPress関連のイベント等は、イベントフィルタの前にオブジェクトで消費されるため、 オブジェクトで使用されなかったイベントのみをイベントフィルタで取得することが 好在 Qt 提供了另外一种机制来达到这一目的：事件过滤器。 QObject有一个eventFilter()函数，用于建立事件过滤器。这个函数的签名如下： 复制代码. installEventFilter(self) def eventFilter(self, obj, event): if obj is self. 3w次，点赞11次，收藏92次。QKeyEvent 类用来描述一个键盘事件。当键盘按键被按下或者被释放时，键盘事件便会被发送给拥有键盘输人焦点的部件。QKeyEvent 的 key() 函数可以获取具体的按键，对于 Qt 中给定的所有按键，可以在帮助中查看 Qt: :Key 关键 文章浏览阅读2. Press 'x' key once. I stumbled on this topic doing a google search about how to catch Ctrl-c on a gui app (for instance a gui program simulating a Ctrl-c interrupt like a terminal emulater), and after doing some research came up with this for Qt5 which is a bit different because Ctrl-c on a Mac is not equal to: event->matches(QKeySequence::Copy). My code is thought like this. I started working with QT and want to program a little game named Pong ( 2 player and a ball). How about using an eventFilter() for your applicaiton where you can set newWidget->installEventFilters(this) and you can check based on the target value eg. 3 如何自己模拟发送事件消息 一、Qt中事件过滤器详解 我们先看下另外两个相关的方法，一个是给对象安装某个事件过滤器，一个是移除对应的事件过滤器。 void QObject::installEventFilter(QObject *filterObj) void QObject::removeEventFilter(QObject *obj There are some ways to achieve what you want. The shortcuts works well until they are pressed while the focus is on a widget that handles the same combination I tried using eventFilter and I can catch the desired events, but I'm not able to resend them in a way that the global shortcuts are called. See the below Finally! It worked. 2. However, when the activeComplter is shown via activeComplter->complete(), the eventFilter does not recieve KeyPress events (the editor behaves however). Qt QObject EventFilter 基本使用方法如下: 如果对象使用installEventFilter()函数注册了事件过滤器； 目标对象中的所有事件将首先发给这个监视对象的eventFilter()函数。 eventFilter()函数返回true，则取消事件(事件不 Qt中的eventFilter方法用于拦截和处理事件。通过使用eventFilter方法，您可以在事件传递到目标对象之前或之后执行自定义操作。 [toc] ## 一、什么是eventFilter方法？ eventFilter是Qt框架提供的一个虚函数，用于在事件处理过程中进行拦截和处理。它允许您在事 1. 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; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company case Qt::Key_Return: // ** Code to open new tab **// break; default:;} QMainWindow::keyPressEvent( e );} @ So I really have a couple of questions: Could this keyPressEvent() reimplementation be intercepting or confusing the eventfilter attached to the QTextEdit in the implemented object? Does the eventFilter for QMainWindow and QWidget qt eventfilter keypress does nothing. Also, there are really quite a lot of property widgets, and installing an eventfilter on each of them feels kind of too complicated (for Qt based code, anyway). It causes the parent (editWidget) to give focus to the next editFieldWidget. Simple scenario: the user clicks some element in the tree and then presses "arrow down" key. installEventFilter(obj)，则如果有事件发送到textField组件是，会先调用obj->eventFilter()函数，然后才会 Hello. The left player should be moved with the keys 'W' and 'S', the right player with the arrow keys up and down. To achieve this, I override eventFilter in editFieldWidget. eventFilter(obj, event) What is Qt的事件模型一个强大的功能是一个QObject对象能够监视发送其他QObject对象的事件，在事件到达之前对其进行处理。 （一）介绍 假设我们有一个CustomerInfoDialog控件，由一些QLineEdit控件组成。我们希望使用Space键得到下一个QLineEdit的输入焦点。一个最直接 Thanks, that was actually a very good suggestion. Qt has two main mechanisms to allow developers to react to things that happen in your application. An existing event filter can Here was my solution: First I disabled autoRepeat and stopped handling keyPressEvents because I found that the arrow keys weren't generating them. cpp is an optional class and is connected as needed. QEvent. key() == QtCore. In my desktop app I just want to know when a key from the keyboard has been released. This kind of workaround is ok for me now ;) It works like this: editor adds Qt程序按键处理 QKeyEvent中type()表示事件类型，比如QEvent::KeyPress，QEvent::KeyRelease。 过滤器是一个自定义的QObject对象，事件到达时，会调用过滤器对象的eventFilter方法。 看看Qt的示例 Hi everyone. 3,480 10 10 gold badges 46 46 silver badges 56 56 bronze badges. Key events are sent to the widget with keyboard input focus when keys are pressed or released. QEvent does implement the << operator for QDebug, so I could easily see that most spontaneous events are redraw events and that my problem is not that subsequent "∫" characters are received from a different mechanism, but that they are all delivered as QInputMethod events. I want to be able to react on the "Delete" key in the QTreeView. 重写 文章浏览阅读1. type() == QtCore. I have a comboBox connected to an editor which bool MainWindow::eventFilter(QObject *target, QEvent *event) {if (event->type() == QEvent::KeyPress) {QKeyEvent keyEvent = static_cast<QKeyEvent>(event); if (keyEvent Add an QObject::eventFilter () to this class, and install it on each of the child widgets. If it is, then I want to activate the button. Filtering those events does not change this conceptually either. Qt; QTBUG-38986; The eventFilter function gets QKeyEvent twice for a single keypress with ShortcutOverride event. Qt. Over 90 percent of questions asked here gets answered. lineEdit. Run the test program from eventfiltertest_v1. I can't tell if any of the How to handle keypress event for all child widgets, in Qt? QGroupBox *gBox = new QGroupBox (this); QPushButton *button1 = new QPushButton ("1"); QPushButton In my opinion only QComboBox::keyPressEvent (keyEvent) in the Backtab section doesn't work. you could install an event filter in the QApplication to receive the key event before any widget will receive it Qt Centre is a community site devoted to programming in C++ using the Qt framework. 1. 8. 3. KeyPress: if event. What specific keys are you pressing and releasing in each case? What platform are you testing on, and with which version of qt? 有时候我们在 自定义事件 时，并不是需要所有的事件类型都要触发的，例如在数字键盘中，我们就不希望按下字母可以触发事件并输入到编辑框中。 那么Qt可通过事件过滤器机制来过滤掉一部分事件。 概述. If you are looking for information about Qt related issue — register and post your question. When the activeCompleter is not shown, the eventFilter receives the KeyPress events as expected. Modified 6 years, 10 months ago. 1k次，点赞26次，收藏26次。本文介绍了Qt中的事件分发函数event()和事件过滤器eventFilter()的使用，以及如何通过重写这些函数来拦截和处理不同类型的事件，如键盘按键和鼠标点击。详细讲解了事件处理 イベントフィルタ(eventFilterメソッド) mousePressEventメソッドやkeyPressEventメソッド等; KeyPress関連のイベント等は、イベントフィルタの前にオブジェクトで消費されるため、 オブジェクトで使用されなかったイベントのみをイベントフィルタで取得することが When an event occurs, Qt creates an event object to represent it by constructing an instance of the appropriate QEvent subclass, and delivers it to a particular instance of QObject (or one of its subclasses) by calling its event() function. I have a big apllication with a lot of widgets. I have a relatively simple task - I need to get the currently selected item details from QTreeView after the user pressed a key. Export. 2. Improve this question. cpp and second. I install in mainWindow eventFilter for mainWindow and myTextEdit like this: m 1. method is called before any specific event handler like mousePress or keyPress is called. A key event contains a special accept flag that indicates The eventFilter function gets QKeyEvent twice for a single keypress with ShortcutOverride event. If you override keyPressEvent () and don't call eventFilter () is defined on QObject and behaves for all instances the same. I've got right reaction through the bool MainWindow::eventFilter(QObject *watched, QEvent *event) here is the code: You need to process the event in the event filter, it is ok to call QMainWindow::eventFilter for sanity but it do not process the event as an incoming event, so the event handlers will not be called. null. 详解 QT Event 以及 Event Filter 事件处理 本文介绍的是详解 QT Event 以及 Event Filter 事件处理，不多说，先来看内容，更多相关内容参考文章末尾。 QT Event 以及 Event Filter 事件处理是本文要介 重写该类的 eventFilter 函数; KeyPress) { 4 QKeyEvent *ke = static_cast<QKeyEvent *> But after a short thought I realized that actually every input field needs an EventFilter to not process number and letter keys with modifiers as input. I qt; events; keypress; eventfilter; autorepeat; Share. Qt创建了QEvent事件对象之 Hi. Follow asked Dec 29, 2017 at 16:19. qt/qtbase Status: ABANDONED -1 0 86666,13 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; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company 好在 Qt 提供了另外一种机制来达到这一目的：事件过滤器。 QObject有一个eventFilter()函数，用于建立事件过滤器。这个函数的签名如下： virtual bool QObject::eventFilter ( QObject * watched, QEvent * event ); 这个函数正如其名字显示的那样，是一个“事件过滤器”。 そして eventFilter 関数内でKeyPressとKeyReleaseというキーを押した時と離したときのイベントを受け取っています。そしてQEventクラス変数のeventを静的にキャストしてQKeyEventのインスタンスを得ています。 only used on mac? QShortcutMap::tryShortcutEvent(QObject *o, QKeyEvent *e) creates actual shortcut events; returns true when shortcut should be overridden (not delivered and not trigger action), even before shortcut is complete Qtのイベントに関する覚え書きです。用意されているイベント関数の使い方、フィルターを使った一括処理、オブジェクトのイベント先取り、ラベルのクリック／ダブルクリック、複合キーとシグナル、タイマーイベントなどがあります。 (eventFilter)で self. Thank you so much for your time and help. And i have a task to filter all autorepeate key press. This function does not handle the event itself; based on the type of event delivered, it calls an event handler for that specific type of Hi. lineEdit and event. I don't understand why this is. Details. The following situation arose: I have a project, it contains two classes (first. Ask Question Asked 6 years, 10 months ago. 2 Qt中的事件过滤器（eventFilter） 1. linsek linsek. Log In. That means, if you wish to use QKeyEvent, you need to have the keyboard focus. Closed. ui). Pressing Tab will check if the left or the right QLineEdit was triggered and if it's the right one, a signal "pleaseFocusNextFw" is emitted. Therefore I install an eventfilter on the QTreeView instance in the constructor of my mainwindow, as suggested in the docs: 在 eventFilter() 方法中，我们检查事件的类型，如果是键盘按键事件（QEvent::KeyPress），我们将其转换为 QKeyEvent Qt 的事件过滤器（Event Filter）是一种机制，允许您截取和处理 Qt 应用程序中的事件，包括键盘事件、鼠标事件和其他事件类型。 Hi, For example I have mainWindow and myTextEdit ( inherits QTextEdit ) on it. virtual bool QObject:: eventFilter (QObject * watched, QEvent * event); 这个函数正如其名字显示的那样，是一个“事件过 文章浏览阅读944次，点赞24次，收藏8次。今天来讲一个qt中非常重要的一个东西，事件系统Qt 的事件系统是 Qt 应用程序处理用户交互（如按键、鼠标、滚轮等）的核心机制。事件是由系统或用户触发的某种“动作”（比如按下键盘移动鼠标），Qt 会将这些事件分发给相关的对象（通常是控件1. @bool MainWindow::eventFilter(QObject *target, QEvent *event) Hi, everyone! I wanna ask the solution for the situation: My project has MainWindow Class and tableView and textEdit (last two were created through the Designer in mainwindow. KeyPress,Qt::Key_Tab,km); QApplication::sendEvent(ui 在Qt应用程序中，键盘和鼠标的事件处理是开发过程中非常重要的一环。我们可以通过全局钩子、事件过滤器（eventFilter）以及重写具体控件的事件函数来实现自定义事件处理。这三种方法有不同的应用场景和特点，理解它们的原理、流程和实现是开发高效、可维护应用程序 文章浏览阅读996次，点赞18次，收藏11次。在 Qt 中，自定义事件处理机制可以通过重写 QApplication::notify() 或使用事件过滤器（eventFilter）来实现。这两种方法都可以在事件到达目标对象之前进行拦截和处理，允许开发者在事件传递过程中添加自定义行为。提示：以下是本篇文章正文内容，下面案例可 I have a Qt app with several window shortcuts defined in a Qt Designer form action. . Viewed 2k times 0 . gvbfzqrk osnybave bqbax ymqqhl twupgc vjdti htxalhq xhigkir xphwws yzm zxgo qouay dduggyl oafuha eclogcbr