Qt 4.8: QWSEvent Class Reference

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# QWSEvent Class Reference

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

     #include <QWSEvent>

- List of all members, including inherited members

## 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.

Constant | Value | Description
--- | --- | ---
`QWSEvent::NoEvent` | `0` | No event has occurred.
`QWSEvent::Connected` | `1` | An application has connected to the server.
`QWSEvent::Mouse` | `2` | A mouse button is pressed or released, or the mouse cursor is moved. See also Qt for Embedded Linux Pointer Handling.
`QWSEvent::Focus` | `3` | A window has lost or received focus.
`QWSEvent::Key` | `4` | A key is pressed or released. See also Qt for Embedded Linux Character Input.
`QWSEvent::Region` | `5` | A region has changed.
`QWSEvent::Creation` | `6` | The server has created an ID, typically for a window.
`QWSEvent::PropertyNotify` | `7` | A property has changed.
`QWSEvent::PropertyReply` | `8` | The server is responding to a request for a property's value.
`QWSEvent::SelectionClear` | `9` | A selection is deleted.
`QWSEvent::SelectionRequest` | `10` | The server has queried for a selection.
`QWSEvent::SelectionNotify` | `11` | A new selection has been created.
`QWSEvent::MaxWindowRect` | `12` | The server has changed the maximum window for an application.
`QWSEvent::QCopMessage` | `13` | A new Qt Cop message has appeared. See also QCopChannel
`QWSEvent::WindowOperation` | `14` | A window operation, e.g. resizing, has occurred.
`QWSEvent::IMEvent` | `15` | An input method has been used to enter text for languages with non-Latin alphabets. See also QWSInputMethod.
`QWSEvent::IMQuery` | `16` | An input method query for a specified property has occurred. See also QWSInputMethod.
`QWSEvent::NEvent` | `21` | The number of events has changed.
`QWSEvent::Embed` | `18` | An event used internally to implement embedded windows. See also QWSEmbedWidget.
`QWSEvent::ScreenTransformation` | `20` | An event used internally to notify the client processes that the screen has changed for example, rotation, etc.