event – PySide6. Also, to use type T with the QObject::property() API, qRegisterMetaType() must be called before it is used, typically in the constructor of the. It associates a type name to a type so that it can be created and destructed dynamically at. qRegisterMetaType 将某类型注册中 MetaType 系统中. Call this function if you need QLocalSocket to start sending buffered data immediately. @pyqtSlot, in turn, is a decorator which converts simple python method to Qt slot. If that is. Appears to the right of the line. You can use Qt's typedef for unsigned char: quint8 and you don't need to register it. By convention, these files are given a . 150%) wider. The following code allocates and destructs an instance of MyClass:The Q_DECLARE_METATYPE() macro and qRegisterMetaType() function documentation contain more detailed information about their uses and limitations. Otherwise, returns QPartialOrdering::Less, QPartialOrdering::Equivalent or QPartialOrdering::Greater if lhs is less than, equivalent to or. Use Q_DECLARE_OPAQUE_POINTER () to be able to register pointers to forward. Returns the internal ID used by QMetaType. )" caused by working in threads. Qt5でシグナルの引数としてユーザー定義型を指定する場合は、 Q_DECLARE_METATYPE と qRegisterMetaType () を使って方の登録を行う必要が. The Qt Meta-Object System in Qt is responsible for the signals and slots inter-object communication mechanism, runtime type information, and the Qt property system. Learn more about TeamsAh I found the problem, which was a logic problem. Re: How to use Q_DECLARE_METATYPE. ) QObject::connect: Cannot queue arguments of type 'QVector<int>'. Re: Q_DECLARE_METATYPE vs qRegisterMetaType for non global namespace classes (QTest) The reason for this behavior might be caused by the fact that runtime signal/slot connections are checked by string manipulation - both Q_DECLARE_METATYPE, SIGNAL, SLOT macros and 'moc' are (among other things) converting type-names to text and pass it along. ) but I do not think that relates with the phenomena. If you wanted to user the new-style signals, then it would look more like: class TwitterThread (QThread): newStatuses = pyqtSignal (object). 16. I pass the MyClass pointer to the streaming operator and only stream things like QString, QPointF, etc. Note that if you intend to use the type in queued. Replacing it with "%matplotlib qt5" (or deleting it entirely) worked for me. qmlRegisterType makes the QObject (MyClass) class accessible in QML (Q_PROPERTY, Q_ENUM, Q_SIGNAL, Q_SLOT, Q_INVOKABLE, etc. Usually one puts this (note that the typedefed name is used as string argument): qRegisterMetaType < QSharedPointer < TestClass > > ( "SharedTestClass" );To use the type T in queued signal and slot connections, qRegisterMetaType() must be called before the first connection is established. Handler. qRegisterMetaType 将某类型注册中 MetaType 系统中. struct StandardData { int EmpId; QString Name; }; Q_DECLARE_METATYPE (StandardData) Additionally, you might need to call qRegisterMetaType. Call qRegisterMetaType() to make types available to non-template based functions, such as the queued signal and slot connections. Use wakeOne() to wake one randomly selected thread or wakeAll() to wake them all. See QMetaType docs for more information. しかし、Qtを使っている場合は、わざわざ自分でMutexの管理をしなくても、スレッドとのデータのやり取りを全て signal/slotでやってしまい、共有データを. As you have already found out, you must use Q_DECLARE_METATYPE to make the type known to Qt. e. The entries are addressed via startAddress () and the valueCount () number of contiguous entries. The QML engine provides built-in support for a large number. If you are using queued connections, you need to register std::string as meta type. QObject::connect: Cannot queue arguments of type 'QVector<QVector<int> >'. The registrations must have happened after doing a foo::FooUsingClass *f = new foo::FooUsingClass();. 2 @Alfredocubitos would it be possible to share an example of the threaded websocket. qRegisterMetaTypeしているにもかかわらずQObject::connectでランタイムエラーが出る場合の回避策. Be very careful as cv::Mat is not implicitly shared, it is just shared (i. emit() create new model elements that have QPersistentModelIndex associated that are not thread-safe and that Qt monitors its creation to warn its misuse as in this case since modifying that element is unsafe since it implies. This implies that you can create bindings that use this property as a dependency or install QPropertyObserver objects on this property. ) # 切换rviz配置文件 terminate called after throwing an instan. I had to uninstall it first, then reinstall it: # upgrade pip python3 -m pip install --upgrade pip # uninstall python3 -m pip uninstall PyQt5 python3 -m pip uninstall PyQt5-sip python3 -m pip uninstall PyQtWebEngine # reinstall python3 -m pip install PyQt5 python3. #include<QMetaType> typedef QList<int> IntList; qRegisterMetaType<IntList> ("IntList"); error C2909: 'qRegisterMetaType': explicit. And once all of them are updated I'd like the Context object to inform QML to update the view. 1、自定MyDataType 类型，在这个类型的顶部包含：#include <QMetaType>. )@. You need to create your own factory that will register functors that will call qRegisterMetaType in runtime. 独自の QTcpServer を構築する. king_nak king_nak. QtCore import * from PyQt5. Note: If you want to use your custom metatypes also in queued slot connections or with QMetaMethod, you have to call qRegisterMetaType<QPushButton*>() Share. 2 Answers Sorted by: 3 You do not need to call qRegisterMetaType () to use a type with QVariant. QPainter supports drawing lines, polygons, vector paths, images, and text. QObject::connect: Cannot queue arguments of type 'uint32_t' (Make sure 'uint32_t' is registered using qRegisterMetaType(). 我们知道类中的成员函数并不一定会被调用(即，该宏并不确保类型被注册到MetaType)。 通过qRegisterMetaType可以确保类型被注册 ; 两个qRegisterMetaType 的联系QObject::connect: Cannot queue arguments of type 'QHostAddress' (Make sure 'QHostAddress' is registered using qRegisterMetaType(). 0’ of a module called ‘com. The ones I am registering for are mostly structs for storing data and just a few simple classes. How to properly use qRegisterMetaType on a class derived from QObject? I couldn't understand from the answer to where I have to define the specialization of qMetaTypeConstructHelper. 0. Here my test code and example: #include <QCoreApplication> #include <QDebug> #include <QMetaType> #include <QRect> #include <QMetaObject> class. The physical memory sizes returned include the memory from all nodes. 它的作用是将自定义的数据类型转换为Qt元对象系统中的类型，使得这些类型可以在不同线程之间进行信号槽的传递。. adam-iris added a commit that referenced this issue Oct 10, 2017. Using the macro directly turned out to be impossible. Not sure yet. Hello! connect( threadEstudo, SIGNAL( sinalResultados ( QList<analysis_results>)), this, SLOT( slotAvaliaResultadosEstudo ( QList<analysis_results>))); You may notice that I put the qDebug () so I can check if all metatypes were correctly registered, and the result was. If I register QVector I can't dissconnect this signal and the signal is emited. QMetaMethod::Access QMetaMethod:: access const. 默认会发送给主线程即默认的连接Qt::AutoConnection ，如果是多线程的话就是Qt::QueuedConnection了，所以要明确指定。. Undeclared QMetaObject::SuperData. Doc states:. ) It still works but point to the fact that I am doing something wrong, and I am not sure that I will keep working when more threads are active. In QML, the meta-type system is the only way that QML engine can access C++ structures from a QML environment. 1 Reply Last reply . childKeys();@J. #include <QObject> #include <QVariant> class Record : public QPair<qreal, qreal> {. Registers the type name typeName for the type T. Returns the access specification of this method (private, protected, or public). As the docs state: Declare new types with Q_DECLARE_METATYPE () to make them available to QVariant and other template-based functions. That always worked in Qt4, but in Qt5 I get the following error: @error: specializing member ‘::qRegisterMetaType’ requires ‘template<>’ syntax@ qRegisterMetaType("Subclass") also doesn't workI am using ubuntu 16. Bachir. 因为没有指定 connect的链接方向 Qt::DirectConnection. I'm running the livox horizon lidar on one PC and running the loam on a different PC. qRegisterMetaType<MyStruct>("MyStruct"); 若已经使用 Q_DECLARE_METATYPEQ 标记过该类型，可以使用其不带参数的版本： qRegisterMetaType<MyStruct>(); 同样的，若对象包含在自定义的命名空间中时，注册时要带上完整的命令空间，如： qRegisterMetaType<NSP::MyStruct>("NSP::MyStruct"); Note that for enum types, you no not even need to call qRegisterMetaType () in these cases. If you need a socket, you have two options: Instantiate QTcpSocket or QUdpSocket. I am trying to learn Qt and I am attempting to do so by making a little titres game. ) @. It works only in this case int qmlTypeId = qRegisterMetaType<namespace::MenuModel*> ("MenuModel*"); You return a pointer in the property, so Qt Meta Object system needs to know about it. 4 and it seems to work. Following this logic, the following code may not work: connect (senderObject. (Make sure 'QVector<int>' is registered using qRegisterMetaType (). ) When I do . 1 Answer. It will look for the signature of methods using string matching. You can try it:This function registers the Python type in the QML system with the name qmlName, in the library imported from uri having the version number composed from versionMajor and versionMinor. QDBusArgument is the central class in the Qt D-Bus type system, providing functions to marshall and demarshall the primitive types. Instead, the enum should be registered as soon as the shared library is loaded. This requires the exchanged data to be of a type that is recognizable by the engine. The central feature in this model is a very powerful mechanism for seamless object communication called signals and slots . Normally you would do this in main () or. QBluetoothDeviceInfo which provides similar information for remote devices. One of these objects is a Connection. Share. This is the same as indexOfMethod (), except that it will return -1 if the method exists but isn't a signal. @reddy9pp said in QObject::connect: Cannot queue arguments of type 'std::string' (Make sure 'std::string' is registered using qRegisterMetaType(). hskoglund last edited by . launch" and then "roslaunch velo2cam_calibration laser_pattern. Thanks for replying! I'm using Qt 5. iii. emit (statuses) Share. . Share. ) I got the hint "expected a declaration" when I tried to use qRegisterMetaType from the global scope in my cpp file. Otherwise you might be adding duplicate entries to the metatype database each time. rows += self. If I save it just at the beginning of. Where: before using any of the above. • Posting events with QApplication::postEvent(), or using queued signal/slot connections, are both safe mechanisms for communicating across threads but require the receiving thread. ) changing rowCount in the main thread or commenting out setRowCount call in change_row_count() makes those errors. Follow. qRe gisterMetaType 的函数原型为： ```c++ template < type name T> int. The operating system can enlarge the paging file up to the maximum size set by the administrator. If I save the image to disk in the DB thread just after emitting the signal, it is good. Since you're passing the parameter via a pointer you don't need to register the type AFAIK. Note: Signals are always public, but you should regard that as an implementation detail. Foo and Foo* are different types and need to be registered separately. Debugging signals and slots connections. 1,609 4 22 34. setContextProperty qmlRegisterType qRegisterMetaType等区别. ) Is this a reminder t. if the permission was not granted or has been changed to NOT granted, the user is asked to grant permission. Nov 30, 2012 at 8:31. ; Create a native socket descriptor, instantiate QAbstractSocket, and call setSocketDescriptor() to wrap the native socket. Now the above code compiles and runs just fine. ) I read about qRegisterMetaType() and try to implement it in the constructor of both classes, like this:. Can you show the code that's actually causing the error? The. MainWindow win; win. However, as you need the type to be. What worries me is that. 0. ) You can read about how to call qml functions from c++. QVariants are important in QML because they used to store the arguments from signals and slots, and also get values from the QMetaProperty system. tag(); // prints MY_CUSTOM_TAG. 2. From the docs: int qRegisterMetaType ( const char * typeName ) Registers the type name typeName to the type T. QAbstractSocket is the base class for QTcpSocket and QUdpSocket and contains all common functionality of these two classes. QSignalSpy can connect to any signal of any object and records its emission. newStatuses. In my module tests, I turn the card up and down, and can verify that the number of signals are increasing using QSignalSpy. Nejat Nejat. Use it if you want to use it as a global enumerator and then you need to call the meta-type runtime registration from the library, not from the application. Section and Key Syntax# Setting keys can contain any Unicode characters. That's probably there, as qRegisterMetaType () wouldn't compile otherwise. Here how connect looks in main constructor: connect (w1, SIGNAL (sentInt (int)), this, SLOT (receiveInt (int))); Such simple app works, but if i change parameters from int to "signed long long" it will give message during runtime and signal won't be emitted: QObject::connect: Cannot queue arguments of type 'signed long long'. So, what is the right way to get rid from: QObject::connect: Cannot queue arguments of type 'QTextCursor' (Make sure 'QTextCursor' is registered using qRegisterMetaType (). (Make sure 'QTextCursor' is registered using qRegisterMetaType (). rep file extension, short for Replica. Instead, we should pass weak_ptr to a shared_ptr. This function was introduced in Qt 6. I understand that it has to do with Qt library but in which cpp file i have to put the argument ? The argument is this right ? qRegisterMetaType<QVector<int> >. Note that this only works for QObject subclasses which use the Q_OBJECT macro. no unexpected garbage. 用qRegisterMetaType对自定义的类型进行注册，就是为了告诉Qt如何去做这些事情。. ) On any update in C++ side list, modify the qml data as well. The Rep lica C ompiler (repc) generates QObject header files based on an API definition file. 2 Answers. A common way to register the type is in main or with a static function register. QObject::connect: Cannot queue arguments of type 'MyStruct'. For pointer types, it also requires that the pointed to type is fully defined. {. If you are using those metatypes during. The stretch factor changes the width of all characters in the font by factor percent. Asking for help, clarification, or responding to other answers. . I also have to implement for cv::Mat type data. You can create Q_GADGETS in QML using a C++ factory object registered to be accessible in QML, and a Q_INVOKABLE function in this factory which returns an instance of the Q_GADGET object. The Windows registry and INI files use case-insensitive keys, whereas the CFPreferences API on macOS and iOS uses case. You can define one with the enum keyword. QTextCursor contains information about both the cursor's position within a QTextDocument and any selection that it has made. All the resources I found online point to a C++ syntax/documentation. qRegisterMetaType() since the names are resolved at runtime. As far as I found before, Qt objects should not be accessed directly. template <typename T> int qRegisterMetaType (const char *typeName) This function is deprecated. Jun 13, 2021 at 19:37. call qRegisterMetaType with the name specified, else reading properties. QT 如果直接传递自定义的对象会报错导致信号和槽无法连接成功，这里提供两种方法解决 1、传递对象指针：信号和槽在传递自定义对象时，改为传对象指针。. It provides a safer and easier way to manage dynamic memory allocation and deallocation by automatically managing the reference counting of a shared object. I am also using some in queued signal and slot connections. When a new folder is selected I load the thumbnails and. e. Variant 2: use std::invoke inside a lambda, which is passed to QMetaObject::invoke. qRegisterMetaType<QVector<int> > ("QVector<int>"); Once you make this call, you should be able to emit the QVector type over queued connections. Reproducible Example Of The. text_changed. QObject is the heart of the Qt Object Model . Any class or struct that has a public default. Inheritance diagram of PySide6. Adding a Q_DECLARE_METATYPE() makes the type known to all template based functions, including QVariant. std::shared_ptr does not let you assign a plain pointer to it directly. If a field is empty, keep it in the result. Hm. It's a bit tricky thing. I'll take your word on that, because on my rig fixing the return type of area() and providing the empty template parameter list for the specialization leaves only get() failing to compile, and as near as I can tell it may be because of the order this was pasted into the question. QObject. If it is a partial specialization it might be template<class X> instead. 如果要使自定义类型或其他非QMetaType内置类型在QVaiant中使用，必须使用该宏Q_DECLARE_METATYPE。该类型必须有公有的 构造、析构、复制构造 函数 qRegisterMetaType 必须使用该函数的两种情况：1、如果非QMetaType内置类型要在 Qt 的属性系统中使用2、如果非QMetaType内置类型要在 queued 信号与槽 中使用。错误原因：. qRegisterMetaType<geometry_msg::msg::Pose>(); // In MainWindow's constructor. 步骤： (以自定义MyDataType类型为例）. 5. Currently, on Linux and Android it is used for specifying connection to a server listening to a socket bound to an abstract address. 1 Answer. Custom types registered using qRegisterMetaType() that have operators for streaming to and from a QDataStream can be stored using QSettings. ) The image I am trying to pass is a cv::Mat which I converted to a QImage which I afterwards converted to a QString. Any class or struct that has a public default constructor, a public copy constructor, and a public destructor can be registered. ) I read on some forum, that this may be caused by calling qt-functions from another Thread, and that using signals & slots instead of plain function calling may fix the issue, but i have tried signals aswell, and i. Qt also has a macro Q_DECLARE_METATYPE, which is expanded and specialized in the class QMetaTypeId. Add a comment | 5 I believe the following is state is not defined in your MyThread class. FollowThis can be made to work but it turns out there's a bit of manual labour to be done. Got a similar example working without explicitly calling qRegisterMetaType() just by removing the semicolon from the line Q_DECLARE_METATYPE(StateMachine::state) – user666412. The file (called a "rep" file) uses a specific (text) syntax to describe the API. When: when you need to pass arguments to a queued connection or to enable creation of objects at run-time. Haven't tried it yet but it appears to check the permissions established in the manifest(?). This results in access violations. One of these plugins uses Q_DECLARE_METATYPE on some types that need to be stored in a QVariant. clicked. Although you can just create QBluetoothDeviceInfo objects on your own and fill them with data, the easier way is to use the QBluetoothDeviceDiscoveryAgent to start an automated search for visible Bluetooth devices within the connectable range. QObject::connect: Cannot queue arguments of type 'QVector<int>' (Make sure 'QVector<int>' is registered using qRegisterMetaType(). QtCore. Use Q_DECLARE_METATYPE (std::string) in one of your headers. The following example illustrates how a structure containing an integer and a string. void QVariant:: clear (). It enables storing your types in QVariant, queued connections in. emit (foo_text) def settext ( self, text ): print (text) Im sure you guys get this alot but im trying to thread and im getting this error: (Parent is QTextDocument (0x1243bfd4290), parent's thread is QThread (0x12437dd1260), current thread is. 1 Reply Last reply 0. qRegisterMetaType usage. call qRegisterMetaType() to register the data type before you establish the connection. Data Type Conversion Between QML and C++. ) QObject: Cannot create children for a parent that is in a different thread. The QAbstractSocket class provides the base functionality common to all socket types. ) What I have done is, declare in the main the qRegisterMetatype but it still complaining. 我们知道类中的成员函数并不一定会被调用 (即，该宏并不确保类型被注册到MetaType)。. The QItemSelection class is one of the Model/View Classes and is part of Qt's model/view framework. " and: "Warning: This function is useful only for registering an alias (typedef) for every other use case Q_DECLARE_METATYPE and qMetaTypeId() should be used instead. Detailed Description. You can connect a signal to a slot with connect () and destroy the connection with disconnect () . 2、使用 qRegisterMetaType，将对象注册为元类型 使用qRegisterMetaType对自. So you can call it from your constructor. 2D Graphics #. Yes, all communication between C++ and QML is based on. int QMetaObject:: indexOfSignal (const char * signal) const. 12. Before emitting a signal across a thread boundary with a non-trivial argument type (like QModelIndex ), you must first call this: qRegisterMetaType<QModelIndex> ("QModelIndex"); That prepares Qt to be able to emit the signal across a thread boundary. tab) self. ) What I'm trying to do is send a signal containing two cv::Mat images from a QThread to the main thread, so that I can display the output. The following example records all signal emissions for the clicked () signal of a QCheckBox:Step 1 (mark for MOC), build some QObjects That pattern uses Q_PROPERTY and Q_OBJECT and the MoC tool. (Make sure 'QTextBlock' is registered using qRegisterMetaType (). show(); int functionIndex = win. Where are you getting this from? qRegisterMetaType is not a member function of QSettings or any other class. So the image buffer is maintained internally and thus implicitely shared. Thus the following will fail. bool QMetaProperty:: writeOnGadget ( void * gadget, const QVariant & value) const. October 21, 2020 by Fabian Kosmale | Comments As you might know, Qt has a metatype system which provides run-time dynamic information about types. OTOH, passing it by value in lambdas too is dangerous and can cause memory leaks. akshatrai91 7 Jan 2021, 06:21. Consider for example the following (hypothetical) code:The Listmodel should be modified by an AMQP-Eventqueue. What is(are) the good place(s) to put the qRegisterMetaType call? I obviously don't want any expllicit initialization call from application code. . The constructor does a number of sanity checks, such as verifying that the signal to be spied upon actually exists. the type name must be specified without the class, as in. You can call this function in a subclass of QAbstractSocket to change the return value of the localPort () function after a connection has been established. Thanks for the code snippet. Any class or struct that has a public default constructor, a public copy constructor and a public destructor can be registered in QMetaType. QMetaType:: Q_DECLARE_OPAQUE_POINTER (PointerType) This macro enables pointers to forward-declared types (PointerType) to be registered with QMetaType using either Q_DECLARE_METATYPE() or qRegisterMetaType(). You should use Q_DECLARE_METATYPE macro for this. QObject::connect: Cannot queue arguments of type 'SomeUserDefinedType' (Make sure 'SomeUserDefinedType' is registered using qRegisterMetaType(). And this should be used for each exe/dll instance. How to register custom type with QML if it is passed as const from C++. In this __init__ we create the QPlainTextEdit that will contain the logs. This event handler can be reimplemented in a subclass to receive child events. Toggle Light / Dark / Auto color theme. (Make sure 'QVector<int>' is. Detailed Description. runBtn = QtWidgets. This also makes the type available for queued signal-slot communication as long as you call it before you make the first connection that uses the type. After about 20 seconds of running LOAM, the laserOdometry module crashes with [laserOdometry-2] process has died [pid 6983, exit code -11, cmd /home/ab. There's no compile time error, but when I run. an int and a std::string. You only. Here’s the list of what changed: QVariant used to forward isNull () calls to its contained type – but only for a limited set of Qt’s own types. Hi, you can try using a more robust flavor of connect() by adding an argument after the lambda, like this:We will still need to register it with the meta-object system at run-time by calling the qRegisterMetaType() template function before we make any signal-slot connections that use this type. Qt 避免使用qRegisterMetaType（指针与引用），关注常量,qt,Qt,发出信号： void dbConnected(const QSqlDatabase &db); 我从中学到了如何避免使用 qRegisterMetaType<QSqlDatabase>("QSqlDatabase"); 在吃角子老虎的那一边，我会用这样的东西： void onDBConnected(QSqlDatabase * const db); 我关心的是db的使用（正. You only need to call qRegisterMetaType () if the type will be used in queued signal/slots connections, or with the QObject::property API. 1 Answer. This function requires that T is a fully defined type at the point where the function is called. You always need to inform the compiler that you are specializing a template by placing template<> in front of it. Note: This function is thread-safe. 3. otherwise. The connection in question is queued. Readers will master both the C++ language and Qt libraries,. uint8_t is the typedef for unsigned char . Someone may be able to correct me here, but I don't think you should be needing to register the type int&. This site will remain online in read-only mode during the transition and into the foreseeable future. You can use the tags to annotate your methods. new children are appended at. See also disconnect(), sender(), qRegisterMetaType(), Q_DECLARE_METATYPE(), and Differences between String-Based and Functor-Based Connections. Detailed Description#. 14. 4. The Windows registry and INI files use case-insensitive keys, whereas the CFPreferences API on macOS and iOS uses case. Sorted by: 5. Type names can be registered with QMetaType by using either qRegisterMetaType () or registerType (). However, you shouldn't rely on Qt::QueuedConnection without registering the arguments types using qRegisterMetaType. ) It's a bit tricky thing. ) which are updated by simulation code. ) QObject: Cannot create children for a parent that is in a different thread. ) ^C[rviz-2] killing on exit [laserMapping-1] killing on exit Hello guys, i have the following message when i run the launch file. It contains a bin folder with the exe file and batch launchers, an include folder with the headers, a source folder with the source files and the moc file (cpp). qRegisterMetaType<QSqlDatabase>("QSqlDatabase"); Just changing the signal to this form: void dbConnected(QSqlDatabase *db); And, in the slot side I'll use something like this: void onDBConnected(QSqlDatabase * const db); I'm concerned with the usage of db (as in the beginning I've made the reference const), so I make it const here. tag(); // prints MY_CUSTOM_TAG. Solution 1: somewhere. By implementing a factory it is possible to create custom QNetworkAccessManager with specialized caching, proxy and cookie support. launch, the quads in rviz cannot detect the enviroment and it shows QObject::connect: Cannot queue arguments of type 'QVector' (Make sure 'QVector' is registered using qRegisterMetaType(). And it doesn't make a lot of sense that this particular API will have a. You have to register your custom type for queued signals because by registering it, Qt can make a copy of it in its event loop (which certainly uses QVariant) and pass it as argument later (when the original passed value is long since out. Originally I was passing a pointer to a type to signals which worked, the slots obviously had to returned the same pointer, again this worked. when i use real velodyne VLP16, i got some problem! when i use velodyne VLP16 package,"roslaunch velodyne_pointcloud VLP16_points. 1. mycompany. Adding a Q_DECLARE_METATYPE() makes the type known to all template based functions, including QVariant. runBtn. To not see the message. Any ideas? Nope, registering with qRegisterMetaType<std::vector<int>>() has same effect as not registering at all (using QVector<int> works without registration, but does not expose length, either). A QItemSelection is basically a list of selection ranges, see QItemSelectionRange. Here's the twist: this class is contained in a shared library, and therefore I want to avoid instructing anyone using my library to call qRegisterMetaType. In addition to the limitations of the variadic invoke() overload, the arguments must have the same type as the ones expected by the method, else, the behavior is. – Kamil Klimek. QWaitCondition allows a thread to tell other threads that some sort of condition has been met. 1、自定MyDataType 类型，在这个类型的顶部包含：#include <QMetaType>. But the thing is, I have. This maybe is not the nicest solution, but it works just fine: Add a property to the wizardpage which contains the QListView and let it return the pointer to the selectionmodel. Without this binding click will result in no action. 31. That's not. This enum was introduced or modified in Qt 5. adam-iris added a commit that referenced this issue Oct 11, 2017.