Qt Reference Documentation

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QWSEvent Class Reference

The QWSEvent class encapsulates an event in Qt for Embedded Linux. More...

 #include <QWSEvent>

Public Types

enum Type { NoEvent, Connected, Mouse, Focus, ..., ScreenTransformation }

Detailed Description

The QWSEvent class encapsulates an event in Qt for Embedded Linux.

When running a Qt for Embedded Linux application, it either runs as a server or connects to an existing server. All system generated events are passed to the server application which then propagates the event to the appropriate client.

Whenever the server receives an event, it queries its stack of top-level windows to find the window containing the event's position. Each window can identify the client application that created it, and returns its ID to the server upon request. Finally, the server forwards the event, encapsulated by an instance of the QWSEvent class, to the appropriate client.

The server communicates with the client applications over the UNIX domain socket. You can retrieve direct access to all the events a client receives from the server, by reimplementing QApplication's qwsEventFilter() function.

QWSEvent provides the Type enum specifying the origin of the event. Internally, each type is represented by a QWSEvent subclass, e.g., QWSKeyEvent.

See also QWSServer, QWSClient, and Qt for Embedded Linux Architecture.

Member Type Documentation

enum QWSEvent::Type

This enum describes the origin of the event.

ConstantValueDescription
QWSEvent::NoEvent0No event has occurred.
QWSEvent::Connected1An application has connected to the server.
QWSEvent::Mouse2A mouse button is pressed or released, or the mouse cursor is moved. See also Qt for Embedded Linux Pointer Handling.
QWSEvent::Focus3A window has lost or received focus.
QWSEvent::Key4A key is pressed or released. See also Qt for Embedded Linux Character Input.
QWSEvent::Region5A region has changed.
QWSEvent::Creation6The server has created an ID, typically for a window.
QWSEvent::PropertyNotify7A property has changed.
QWSEvent::PropertyReply8The server is responding to a request for a property's value.
QWSEvent::SelectionClear9A selection is deleted.
QWSEvent::SelectionRequest10The server has queried for a selection.
QWSEvent::SelectionNotify11A new selection has been created.
QWSEvent::MaxWindowRect12The server has changed the maximum window for an application.
QWSEvent::QCopMessage13A new Qt Cop message has appeared. See also QCopChannel
QWSEvent::WindowOperation14A window operation, e.g. resizing, has occurred.
QWSEvent::IMEvent15An input method has been used to enter text for languages with non-Latin alphabets. See also QWSInputMethod.
QWSEvent::IMQuery16An input method query for a specified property has occurred. See also QWSInputMethod.
QWSEvent::NEvent21The number of events has changed.
QWSEvent::Embed18An event used internally to implement embedded windows. See also QWSEmbedWidget.
QWSEvent::ScreenTransformation20An event used internally to notify the client processes that the screen has changed for example, rotation, etc.