removeItem method rather than providing the subsystem an address to connect the function. I shortened the code to be more precise but this has hidden the actual cause. Fix:All of the button's clicked signals will call the same function, passing to the function the associated QPushButton. By voting up you can indicate which examples are most useful and appropriate. Simple painter application based on Qt Widgets. I’ve since found another couple of places in my code that benefit from QSignalMapper since it handles more than QString. void Messenger::addToActivePanels(std::string& channel) { activePanelsContents = this->findChild<QWidget *>(QString("activePanelsContents")); pushButton = new. Im having troubles seeing the readyRead () signal from a bound UDP socket. QSignalMapper. Much thanks to you both. currentIndexChanged. QtCore. Please check the attached snapshot. The following example uses old-style signals and slots connections to explicitly specify the signals to be connected to slots in a Python subclass of QWidget. J 1 Reply Last reply 10 May 2018, 05:28 0. Qt does not do any conversion (cast) even if the sender is a QPushButton object that inherits from QWidget. removeItem, QtCore. QSignalMapper类内置了一个Map表，将Singnal和参数对应起来，然后多个信号关联到Mapper上，由mapper负责管理，并且mapper关联到槽函数中，将对应的参数传入槽函数1. connect(x_slider[0], SIGNAL(valueChanged(int)), this, SLOT(slider_x(int))); but as I don't want to create a slot to every slider in the x_slider array the int received in slider_x slot should be in this case a 0. Here is a simple example. 在. Widgets can be added to menus by using instances of the QWidgetAction class to hold them. QSignalMapper with signal argument and extra argument. I would like to select file via file dialog and upload board with selected file by upload button. The application name is fetched from the Info. By voting up you can indicate which examples are most useful and appropriate. removeItem () in the connect method will actually try to call the self. QObject::connect () works like this (in the general case, not using lambda): connect (obj1, obj1_signal, obj2, ob2_slot) Since there is no signal clicked (int, int) in the class QPushButton (which I assume you are using), it cannot be use for the connection. This is useful when multiple objects need to send a signal to the same slot, but with different parameters. c++; qt; signals; mapper; Share. This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. Python QSignalMapper - 59 примеров найдено. For any interested, I worked around the problem using a closure, which seems a bit cleaner from a coding point of view, although I don't have any idea if it is more efficient or not: I'm trying to use QSignalMapper with my buttons, but I can't seem to get it to work to trigger my slot. h" #endif // QT_H #ifndef QT_NO_SIGNALMAPPER class QSignalMapperData; struct QSignalMapperRec; class Q_EXPORT QSignalMapper : public QObject {. QtCore. because you wrote it in your first answer to this post. The only function that we need to implement is the constructor: A list of texts is passed to the constructor. 1 Answer. Note that in most cases you can use lambdas for passing custom parameters to slots. ) in a loop. It is provided to keep old source code working. The setMapping. This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters. Connect and share knowledge within a single location that is structured and easy to search. The class supports the mapping of particular strings or integers with particular objects using setMapping(). Provide details and share your research!I'm trying to connect a button click to a function, and pass an int value, but keep getting an error: no matching function for call to Main::connect. The. You do not need a QSignalMapper if I understand you correctly but its difficult to tell as you hardly posted any code. Looks like all good. The QSignalMapper class bundles signals from identifiable senders. . Follow asked Jan 31, 2015 at 18:07. If you want to do that, you need to either manually connect everything or otherwise do what this guy described: Can QSignalMapper be used to re-emit signals with multiple parameters? and reimplement QSignalMapper for your specific case. QSignalMapper Class The QSignalMapper class bundles signals from identifiable senders. . However, beside that id it is not possible to extract console pointer,. This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. QSignalMapper is the best solution to connect multiple signals to the same slot. Sorted by: 2. If you need to know both value and sender you either can use some internal class mapping, or use QObject * mapper and then cast QObject * to slider. You could do it with QShortcut fairly easily in code though. The Property System. More. QSignalMapper, полученные из open source проектов. 3. from PyQt5 import QtCore, QtWidgets class Widget (QtWidgets. QAbstractButton provides most of the states used for buttons: isDown () indicates whether the button is pressed down. Mac OS X also has a "Find" clipboard. 详细说明 QSignalMapper 类捆绑来自可识别发送者的信号。. main. QSignalMapper does not update parameter after choosing file. – SPlatten. I suggest that you try copy/paste the following line to replace yours:I know that i can use QSignalMapper to call a slot with different parameters based on connection. #include <QtGui> class W: public QWidget { Q_OBJECT public: W (QWidget *parent=0): QWidget (parent) { // Create. 3. It's actually a problem with QSignalMapper. The overloads are obsolete in Qt 5. It is provided to keep old source code working. You should use direct connection of console and this on readReady (of course with slot of this with void argument as readReady() ). clear () where LineEdits is your list of widgets. Detailed Description#. Once Qt is installed, you can use Maintenance Tool under <install_dir> to add components and to update or remove installed components. Use mapped (QWidget*) and change your slot to have the same signature: button_pushed (QWidget*). 实际上有一种其他技术可以用来获得包装函数和参数的效果。它使用QSignalMapper类，其使用的示例在第9章中显示。 在一些情况下，可以将槽称为信号的结果，并且在槽中直接或间接执行的处理导致最初称为槽的信号被再次调用，导致无限循环。*/ QObject * QSignalMapper:: mapping (QObject * object) const {Q_D (const QSignalMapper); return d-> objectHash. txt"));A. _mapper =. Hope you found it useful. map(sender) Parameters: sender – PySide6. The reason why your QSignalMapper code doesn't work is probably because you are connecting to the wrong overload of the mapped signal. self. I can use the encoded row/column to lookup the QComboBox in the table widget but that seems wrong. The solution is to connect the clicked signal of the different buttons to the mapper directly (rather than through your. plist file in the application’s bundle (See Qt for macOS - Deployment ). 1. @t-vanbesien said in no matching member function for call to 'connect':. QSignalMapper didn't help, because all the properties are in the same object. Note that in most cases you can use lambdas for passing custom parameters to slots. Normally it should not but anyway, nice you found out. If you can't afford to lose the original arguments, or if you don't know the source of the signals (as is the case with QDBusConnection::connect() signals), then it doesn't really make sense to use a. [signal] void QSignalMapper:: mapped (const QString &text) This function is obsolete. AboutRole. QSignalMapper with signal argument and extra argument. 3. This class collects a set of signals without parameter, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. This is less costly and will simplify the code. @Maaz-Momin said in QPushButton "pressed" signal emitting twice when moving mouse: Remember you need to press and move your mouse on a button ("F1" or. QSignalMapper is a class in Qt library that is used to map multiple signals to a single slot. 2. . Instead of accepting an int as an argument, use sender() to determine which button is the source. andrewhopps @hskoglund 2 Apr 2017, 16:14. trigger () behaves correctly, and not act_str. This class collects a set of parameterless signals, and re-emits them with integer or string parameters corresponding to the object that sent the signal. I think you can use this method: [protected] int QObject:: senderSignalIndex () const. mapped [int]. Im creating QSliders and QLabels in my Program and i want to connect them so when I'm changing the Slider the Value should be shown within the label. For a description of simple non-hierarchical list and table models, see the Model/View Programming overview. 15. This is because QML types are resolved at run-time, so they are not available to the C++ compiler. QSignalMapper *mapper = new QSignalMapper. I have a QSpinBox and I would like to connect it to a slot with 2 parameters when clicking on the arrows. I need to implement a simple message bus: One process only thus no need do D-Bus. Signals (and slots) allow you to connect disparate parts of your application together, making changes in one component trigger behavior in another. This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. So for example if you want to have a timer who. QListWidget uses an internal model to manage each QListWidgetItem in the list. Qt Library. The class supports the mapping of particular strings or integers with particular objects using setMapping(). 详细说明 QSignalMapper类捆绑来自可识别发送者的信号。此类收集一组无参数的信号，并使用与发送信号的对象相对应的整数，字符串或窗口小部件参数重新发出它们。该类使用setMapping（）支持特定字符串或整数与特定对象的映射。然后可以将对象的信号连接到map（）插槽，该插槽将发出与原始信令. Types used in signal/slot connections must be fully 'scoped' because the method call is converted into text, so your connection call should look like this: QObject::connect (&myClassA, SIGNAL (theSignal (namespace::myClassA::aStruct)), &myClassB, SLOT (theSlot (namespace::myClassA::aStruct))); You'll probably have to. 我无法将信号映射（QObject*）以触发. Orange widgets are building blocks of data analysis workflows that are assembled in Orange’s visual programming environment. keyboard. Using Maintenance Tool #. 15. A combobox may be editable, allowing the user to modify each item in the list. Salut, Si tu souhaites dépendre de la valeur "n", alors commence par l'ajouter en paramètre de cellActivationRegle. This is an overloaded function. This was particularly true in older versions of the software, that is, and relied on Qt 4. 使用QSignalMapper确定信号的发送者（针对多个发送者的情况） 如果有多个对象都可能发送信号，并且我们希望根据信号发送者来采取不同的操作，可以使用QSignalMapper类。该类可以将多个对象与相应的信号关联起来，并通过sender()方法确定信号的发送者。Many examples show how to do this with QSignalMapper, but it is not applicable when the signal carries a parameter, as with combobox. Finally, the mapped () signal of the QSignalMapper is connected to a slot, which handles the button press by passing the integer value as a parameter. I've written a function called addTab(. Ask Question Asked 8 years, 2 months ago. PyQt and QSignalMapper/lambdas - multiple signals, single slot. " The answer by @kuba, below, is now a better one. When value has hanged, QDialog could emit another signal with information of slider id and new value. currentIndexChanged Many people suggest it can be made with lambda. I can use the encoded row/column to lookup the QComboBox in the table widget but that seems wrong. Several years ago I wrote a short piece on QSignalMapper to give a quick example of how it can be used. This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. When you receive a signal, map (), look at QObject::sender () ( link) as the key in the map to make the emit in your turn. QSignalMapper offers int, QObject*, QWidget* and QString as mapping values. mapper. Eliminate QSignalMapper entirely and connect the button's clicked signal to mySlot. (Going forward the goal will be to have the VerticalLineSegment s in. Share. Remember that from Qt 5. # # Each signal is associated in the QSignalMapper with either an int, # QString, QObject or a QWidget which is passed as argument to the slot # connected to the QSignalMapper. I've recently encoutered a problem with QSignalMapper. Painter Example#. Every slot has an id. QT supports a collection of events through its object QSignalMapper as demonstrated below: signalMapper = new QSignalMapper(this); signalMapper->setMapping(taxFileButton, QString("taxfile. Create Button actually looked like this: void Widget::createButton (const QString &text, int x, int y, const char *member, QString &data) { QPushButton *button = new QPushButton (this); signalMapper = new QSignalMapper. Toggle line numbers. When creating a QSettings object, you must pass the name of your company or organization as well as the name of your application. This slot emits signals based on which object sends. In other words (from the documentation): This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to. You can trigger behaviors in response to user input, such as button presses or text input, or events in your own code. The object's mapped widget is passed in widget. QtConcurrent::map () modifies a sequence in-place, QtConcurrent::mapped () returns a new sequence containing the modified content, and QtConcurrent::mappedReduced () returns a single result. Solved QTimer::singleShot - forward parameter to SLOT called. private: QSignalMapper *signalMapper; private slots: void buttonGeneric (QPushButton &button); signals: void clicked. map ()This method is also a Qt slot with the C++ signature void map(). QSignalMapper is the best solution to connect multiple signals to the same slot. ** **/ #ifndef QSIGNALMAPPER_H #define QSIGNALMAPPER_H #ifndef QT_H #include "qobject. Here's a dummy widget to illustrate that. I've taken the liberty to add example code to your answer. Then, create a standalone. The signal used is valueChanged () from the spinbox The first parameter for the slot would be the spinbox value (imageindex in the slot) and the second one is also an integer (number in the slot). fix deprecated warning int QWheelEvent::delta() break macOS build (Page 1) — Code — QElectroTech —The QSignalMapper class bundles signals from identifiable senders. There is no such signal mapped (const QPushButton&). As such, QSignalMapper is not deisgned to transfer parameters into other slots for you. Just right-click any dock title-bar, or any tool-bar or menu-bar. QSignalMapper 是一个将已知发射对象和信号绑定在一起的类。. to get the ID (can be 1 to 16) and know which ID did kick off the singleShot. Since then, Qt5 has been released and C++11 is now A Thing. QtCore. I'm guessing that I'm not initializing somet. Python QSignalMapper - 59 examples found. The class supports the mapping of particular strings or integers with particular objects using setMapping(). The QSignalMapper class bundles signals from identifiable senders. If you want to have the signal clicked (int, int) in a button, you can subclass. We strongly advise against using it in new code. I am using buttons to switch between states. Instead of connecting and disconnecting the slot one simple solution is to block the emission of the signal using the blockSignals () method. A command button is rectangular and typically displays a text label. ** ** ** ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). QtCore. On the #pyqt channel on Freenode, lauri asked about connecting identically-named signals with different parameters from QSignalMapper to slots. The use of QSignalMapper is not necessary in Qt 5, and is optional in Qt 4. You can rate examples to help us improve the quality of examples. 2. C++ compilation compression computer vision css drag selection example game engine games Guild Wars 2 GW2 html image processing images Info. This is a large example covering many basic uses of maps, positioning, and navigation services in Qt Location. This class collects a set of parameterless signals, and re-emits them with integer, string. A PySide6/QML application consists, at least, of two different files - a file with the QML description of the user interface, and a python file that loads the QML file. ** ** Contact info@trolltech. Also, make sure to register your struct to the Qt metatype system by using Q_DECLARE_METATYPE. Update. When value has hanged, QDialog could emit another signal with information of slider id and new value. In keyboard. ViewObject. QObject. QSignalMapper; QSize; QSizeF; QSocketDescriptor; QSocketNotifier; QSortFilterProxyModel; QStandardPaths; QStorageInfo; QStringConverter;. The signals and slots mechanism is a central feature of Qt and probably the part that differs most from the features provided by other frameworks. The class supports the mapping of particular strings or integers with particular objects using setMapping(). I did not see any problem of your usage of QSignalMapper. What i want to achieve is a little different. Is there a way to clear QSignalMapper, or is QSignalMapper automatically cleared when an object is removed from UI? Now inside of readCombo i want to read a string and pass it to change picture: QString imageFileName = xmlreader->attributes (). It allows you to add add a parameter (in this case, probably an integer index to your vec) to signal, based on which object emitted it. There is no such signal mapped (const QPushButton&). Press Ctrl+a / Ctrl+b to switch between tabs. We would like to show you a description here but the site won’t allow us. void myclass::deleteButton (int i) { delete (Buttons. So I'm dynamically creating QPushButton objects and then mapping them to emit a signal. With setMapping the connection between the sender and the value is set up. This is what I have so far: chess. QWidget): def __init__ (self, parent=None): super (Widget, self). dheerendra Qt Champions 2022 14 Jan 2019, 22:11. @. According to the QT documentation QWorkspace should be replaced with QMdiArea. To avoid such things - use the new signal slot syntax properly described in the documentation. We strongly advise against using it in new code. The problem is when I modify the image inside the Qlabel the update of image works bad. This signal is emitted when map() is signalled from an object that has a widget mapping set. In your Messenger class, you would add a QSignalMapper mapper object, and your function would look like:. The input fields in the main window have no function other than to accept input. I don't know of a way to do this via the Designer, not familiar with that. toString() # store as string inp = coin. I want to use a QObject as a carrier by setting the various information I want to transmit as attributes of the QObject. 2. private: QSignalMapper *mapper; In my cpp: //Constructor: mapper = new QSignalMapper (this); //Init function, called by the constructor connect (mapper, SIGNAL (mapped (int)), this, SLOT. Algunos amigos pueden preguntar, ¿por qué es tan problemático y. Map Viewer Example#. 当然 widget 对应的数据也可以用 property 设置，QSignalMapper 只是一种方式而. All the buttons provided by Qt ( QPushButton , QToolButton , QCheckBox , and QRadioButton ) can display both text and icons . Since a slot has to have the same signature than the connected signal, on_steps_returnPressed becomes on_steps_returnPressed(QWidget*) (cast the parameter to a QLineEdit):The QSignalMapper class bundles signals from identifiable senders. If I click onto a QPushButton, I want to set some text inside the corresponding QLineEdit. The QSignalMapper class bundles signals from identifiable senders. The class supports the mapping of particular strings or integers with particular objects using setMapping (). hIf your pointer is an actual pointer to a QPolygonF that cannot be copied (because it's the pointer to the actual item being held in the QGraphicsScene and you therefore need the original pointer to remove it), I think you should just be able to pass that pointer as-is, assuming mapToScene() is returning a reference to it rather than a copy:. PyQt provides access to all the available. QSignalMapper* signalMapper = new. The main focus is on how the extra input panel can be used to input text without the need for a real keyboard or keypad. So you can have one like: QSignalMapper * mapper = new QSignalMapper(this); QObject::connect(mapper,SIGNAL(mapped(QWidget *)),this,SLOT(mySlot(QWidget *))); The QSignalMapper class bundles signals from identifiable senders. QSignalMapper can not be used for that, but the class is quite simple to re-implement and specialize for your needs. A collection of tutorials with walkthrough guides are provided with Qt for Python to help new users get started. 2 [Русский] Qt Core ; QSignalMapper Class8. This is an overloaded function. Here my QToolButtons are in contained in QList. The Simple Tree Model example shows how to create a basic, read-only hierarchical model to use with Qt’s standard view classes. ote This does not disconnect any signals. Detailed Description. You could simply assign a value to the button with a map ( QMap, std::map) or through a. [slot] void QSignalMapper:: map (QObject *sender) This slot emits signals based on the sender object. Returns true if convert can convert from fromType to toType. This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. This is because QML types are resolved at run-time, so they are not available to the C++ compiler. map) Tonight's PyQt snapshot will be smarter about finding a usable Qt slot before deciding that it needs to. The syntax of a lambda expression is the following: [captured variables] (arguments) {. In this example, the QSignalMapper object is created and connected to the clicked () signal of two buttons. 2 [Русский] Qt Core ; QSignalMapper Class 8. cpp file. It also lets you associate ints, QWidgets, and QObjects to a QAction. There are actually two ways to implement a virtual keyboard with Qt: in-process and out-of-process. QSignalMapper * mapper = new QSignalMapper (this. signal keyboardOpening signal keyboardOpened signal keyboardClosing signal. It behaves essentially like the above function. com if any conditions of this licensing are ** not clear to you. Signals and slots are made possible by Qt’s meta-object. ). and I assume you initialized the "signalMapper = new QSignalMapper (this)" in the MyApp constructor. It does not provide a visual representation of this container (see QGroupBox for a container widget), but instead manages the states of each of the buttons in the group. Use mapped (QWidget*) and change your slot to have the same signature: button_pushed (QWidget*). activeDocument(). . 3 Qt: the signal handler is not called when the signal is emitted. J. I have simple application, a calculator. you might use QButtonsGroup or write your own wrapper over group of buttons, so you initialize this wrapper with them providing mapping between button and some value describing which of them is checked, you can connect each button to slot of this wrapper to update value and you might signal this change from a wrapper using signal-slot. An exclusive button group switches off all checkable (toggle) buttons except the one that. . How to map to overload Qt slot. ) Share. clicked. I have had a look to the logfile of our application, started/cleared yesterday morning. This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. QSignalMapper class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. QSignalMapper is not about sending arguments from signals to slots but to let signal receiver know "who" was that or what data use. 10 QSignalMapper is deprecated: This class is obsolete. I have a QTreeWidget in which each of its items has a QComboBox in a column. SoInput() inp. Detailed Description. QSignalMapper Example Revisited. The slot contains 2 arguments. QImage is designed and optimized for I/O, and for direct pixel access and manipulation, while QPixmap is designed and optimized for showing images on screen. Expecially it is difficult because we have no idea what this is. Detailed Description. 画像のような複数のUIの操作に応じて一つのUIを更新する処理は QSignalMapper が担ってきました。 しかし Qt5 では QSignalMapper は非推奨とされ、 ラムダ式 への置き換えが推奨されます。 Using a signal mapper. QT之QSignalMapper（可以理解为转发器，多个按钮绑定到一个Edit上，且能分辨。每个单独连接的话，反而麻烦） 简述 QSignalMapper我们可以理解为转发器，此话怎讲呢？比如，按钮点击的响应槽，绑定到QSignalMapper上，QSignalMapper收到按钮的点击后，又通知到另外的控件. Tutorials. This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. The class supports the mapping of particular strings or integers with particular objects using setMapping(). Cards are drawn from a deck and displayed on screen. See: QMainWindow::createPopupMenu. Typical buttons are OK, Apply, Cancel, Close, Yes, No and Help. The text of the menu item will be set to “About <application name>”. 3 Answers. MainWindow::MainWindow (QWidget *parent) : QMainWindow (parent) , ui (new. When the content is changed using any of these functions, any previous content is cleared. Maintenance Tool is included in each Qt installation. – jonspaceharperBut this removes all knowledge of the original sender widget. Qt Library. QSignalMapper. void QSignalMapper::setMapping ( const QObject * sender, const QString & identifier ) [virtual] This is an overloaded member function, provided for convenience. It is provided to keep old source code working. How to say QSignalMapper in French? Pronunciation of QSignalMapper with 1 audio pronunciation and more for QSignalMapper. 467. The class supports the mapping of particular strings or integers with particular objects using setMapping(). You shouldn't need to use QSignalMapper with QDialogButtonBox. Download this example17. mapper = new QSignalMapper( this ); connect( mapper, SIGNAL(mapped(QWidget*)), workspace, SLOT(setActiveWindow(QWidget*)) ); I read QSignalMapper can be replaced with lamdas but how in this case? If i understand right mapper forwards all the signals from this to workspaces active window?I think in this case QSignalMapper is the way to go. The QSignalMapper class bundles signals from identifiable senders. Then I discovered QSignalMapper which let me tie a QString to a given action. 该类使用setMapping（）支持特定字符串或整数与特定对象的映射。. 简介. 1. snap1. QSignalMapper. Qt provides four classes for handling image data: QImage, QPixmap, QBitmap and QPicture. For example, if your product is called Star Runner and your company is called MySoft, you would construct the QSettings object as follows: settings = QSettings("MySoft", "Star Runner")I use a QWidget in a Qthread and I had to modify the image in a Qlabel of multiple object. The QSignalMapper class is provided for situations where many signals are connected to the same slot and the slot needs to handle each signal differently. QSignalMapper is not about sending arguments from signals to slots but to let signal receiver know "who" was that or what data use. connect (signalMapper. Qt’s model/view architecture provides a standard way for views to manipulate information in a data source. Who invokes UpdateTempValues? the mapped signal from QSignalMapper, and then who is the sender? it is the object that emits the signal that invokes the slot, in this case QSignalMapper, QSignalMapper can be converted to QSlider? No, does the above explain the problem? – David, thanks for your help. @hskoglund said in Dynamically add buttons to ScrollArea: QHBoxLayout *hlayout = new QHBoxLayout; Edited: That stopped the crashing and the order of code was off, and after rearranging to the following, everything works as originally intended. Theoretically, you could keep a pointer to the signal mapper around, and remap the indexes after deletion. 1 Answer. QSignalMapper类可以看成是信号的翻译和转发器。. . private: QSignalMapper *mapper; In my cpp: //Constructor: mapper = new QSignalMapper (this); //Init function, called by the constructor connect (mapper, SIGNAL (mapped (int)), this,. The code below returns no error, but just the act_int. takeAt (i)); for (int i = 0; i < Buttons. 0. Looks like all good. 15. } Ignoring the “captured variables” part for now, here is a simple lambda which increments. You can connect a signal to a slot with connect (). The QSignalMapper class bundles signals from identifiable senders. 这个思想是：希望能够在信号关联中直接传递一个参数！直接用信号槽无法实现. From the link: "This class is obsolete. Add a comment | Your Answer Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. Viewed 82 times 0 I'm making an application which will be able to program my board. QSignalMapper 主要使用的场景是多个 widget 触发同一个 slot，每个 widget 都对应一个数据(mapper->setMapping() 中设置)，在 slot 中只关心数据，并不关心 widget 是谁，例如计算器。 .