QWSServer Class Reference
[QtGui module]

Input Method Handling

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). Then the server forwards the event to the appropriate client. If an input method is installed, it is used as a filter between the server and the client application.

Derive from the QWSInputMethod class to create custom input methods, and use the server's setCurrentInputMethod() function to install it. Use the sendIMEvent() and sendIMQuery() functions to send input method events and queries.

QWSServer provides the IMMouse enum describing the various mouse events recognized by the QWSInputMethod::mouseHandler() function. The latter function allows subclasses of QWSInputMethod to handle mouse events within the preedit text.

See also QWSInputMethod.

Member Type Documentation

enum QWSServer::IMMouse

This enum describes the various types of mouse events recognized by the QWSInputMethod::mouseHandler() function.

See also QWSInputMethod and setCurrentInputMethod().

enum QWSServer::WindowEvent

This enum specifies the various events that can occur in a top-level window.

See also windowEvent().

Member Function Documentation

void QWSServer::addKeyboardFilter ( KeyboardFilter * filter )   [static]

Activates the given keyboard filter all key events generated by physical keyboard drivers (i.e., events sent using the processKeyEvent() function).

Note that the filter is not invoked for keys generated by virtual keyboard drivers (i.e., events sent using the sendKeyEvent() function).

Note that this function can only be used in the server process.

See also removeKeyboardFilter().

const QBrush & QWSServer::backgroundBrush () const

Returns the brush used as background in the absence of obscuring windows.

See also setBackground().

const QList<QWSWindow *> & QWSServer::clientWindows ()

Returns the list of current top-level windows.

Note that the collection of top-level windows changes as applications add and remove widgets so it should not be stored for future use. The windows are sorted in stacking order from top-most to bottom-most.

Use the QWSWindow::client() function to retrieve the client application that owns a given window.

See also windowAt() and instance().

void QWSServer::closeKeyboard ()

Closes all the keyboard devices (specified by the QWS_KEYBOARD environment variable) by deleting the associated keyboard drivers.

See also openKeyboard() and keyboardHandler().

void QWSServer::closeMouse ()

Closes all pointer devices (specified by the QWS_MOUSE_PROTO environment variable) by deleting the associated mouse drivers.

See also openMouse() and mouseHandler().

void QWSServer::enablePainting ( bool enable )

Enables painting onto the screen if enable is true; otherwise painting is disabled.

See also Qt for Embedded Linux Architecture.

QWSServer * QWSServer::instance ()   [static]

Returns a pointer to the server instance.

Note that the pointer will be 0 if the application is not the server, i.e., if the QApplication::type() function doesn't return QApplication::GuiServer.

This function was introduced in Qt 4.2.

See also clientWindows() and windowAt().

bool QWSServer::isCursorVisible ()   [static]

Returns true if the cursor is visible; otherwise returns false.

Note that this function can only be used in the server process.

See also setCursorVisible().

QWSKeyboardHandler * QWSServer::keyboardHandler ()   [static]

Returns the primary keyboard driver.

Note that this function can only be used in the server process.

See also setKeyboardHandler(), openKeyboard(), and closeKeyboard().

void QWSServer::markedText ( const QString & selection )   [signal]

This signal is emitted whenever some text is selected in any of the running applications, passing the selected text in the selection parameter.

See also windowEvent().

QWSMouseHandler * QWSServer::mouseHandler ()   [static]

Returns the primary mouse driver.

Note that this function can only be used in the server process.

See also setMouseHandler(), openMouse(), and closeMouse().

void QWSServer::newChannel ( const QString & channel )   [signal]

This signal is emitted whenever a new QCopChannel object is created, passing the channel's name in the channel parameter.

See also removedChannel().

void QWSServer::openKeyboard ()

Opens the keyboard devices specified by the QWS_KEYBOARD environment variable.

See also closeKeyboard() and keyboardHandler().

void QWSServer::openMouse ()

Opens the mouse devices specified by the QWS_MOUSE_PROTO environment variable. Be advised that closeMouse() is called first to delete all the existing mouse handlers. This behaviour could be the cause of problems if you were not expecting it.

See also closeMouse() and mouseHandler().

void QWSServer::processKeyEvent ( int unicode, int keycode, Qt::KeyboardModifiers modifiers, bool isPress, bool autoRepeat )   [static]

Processes the given key event. The key is identified by its unicode value and the given keycode, modifiers, isPress and autoRepeat parameters.

The keycode parameter is the Qt keycode value as defined by the Qt::Key enum. The modifiers is an OR combination of Qt::KeyboardModifier values, indicating whether Shift/Alt/Ctrl keys are pressed. The isPress parameter is true if the event is a key press event and autoRepeat is true if the event is caused by an auto-repeat mechanism and not an actual key press.

This function is typically called internally by keyboard drivers. Note that this function can only be used in the server process.

See also sendKeyEvent() and Qt for Embedded Linux Character Input.

void QWSServer::refresh ()

Refreshes the display by making the screen driver update the entire display.

See also QScreen::exposeRegion().

void QWSServer::refresh ( QRegion & region )

This is an overloaded member function, provided for convenience.

Refreshes the given region of the display.

void QWSServer::removeKeyboardFilter ()   [static]

Removes and deletes the most recently added filter.

Note that the programmer is responsible for removing each added keyboard filter.

Note that this function can only be used in the server process.

See also addKeyboardFilter().

void QWSServer::removedChannel ( const QString & channel )   [signal]

This signal is emitted immediately after the given the QCopChannel object specified by channel, is destroyed.

Note that a channel is not destroyed until all its listeners have been unregistered.

See also newChannel().

void QWSServer::resumeMouse ()

Resumes pointer handling by reactivating all the mouse drivers registered by the QWS_MOUSE_PROTO environment variable.

See also suspendMouse() and QWSMouseHandler::resume().

void QWSServer::screenSaverActivate ( bool activate )   [static]

Activates the screen saver if activate is true; otherwise it is deactivated.

Note that this function can only be used in the server process.

See also screenSaverActive() and setScreenSaver().

bool QWSServer::screenSaverActive ()   [static]

Returns true if the screen saver is active; otherwise returns false.

Note that this function can only be used in the server process.

See also screenSaverActivate().

void QWSServer::sendIMEvent ( const QInputMethodEvent * event )

Sends the given input method event.

The QInputMethodEvent class is derived from QWSEvent, i.e., it is a QWSEvent object of the QWSEvent::IMEvent type.

If there is a window actively composing the preedit string, the event is sent to that window. Otherwise, the event is sent to the window currently in focus.

See also sendIMQuery() and QWSInputMethod::sendEvent().

void QWSServer::sendIMQuery ( int property )

Sends an input method query for the given property.

To receive responses to input method queries, the virtual QWSInputMethod::queryResponse() function must be reimplemented in a QWSInputMethod subclass that is activated using the setCurrentInputMethod() function.

See also sendIMEvent() and setCurrentInputMethod().

void QWSServer::sendKeyEvent ( int unicode, int keycode, Qt::KeyboardModifiers modifiers, bool isPress, bool autoRepeat )   [static]

Sends the given key event. The key is identified by its unicode value and the given keycode, modifiers, isPress and autoRepeat parameters.

Use this function to send key events generated by "virtual keyboards" (note that the processKeyEvent() function is impelemented using this function).

The keycode parameter is the Qt keycode value as defined by the Qt::Key enum. The modifiers is an OR combination of Qt::KeyboardModifier values, indicating whether Shift/Alt/Ctrl keys are pressed. The isPress parameter is true if the event is a key press event and autoRepeat is true if the event is caused by an auto-repeat mechanism and not an actual key press.

Note that this function can only be used in the server process.

See also processKeyEvent() and Qt for Embedded Linux Character Input.

void QWSServer::setBackground ( const QBrush & brush )   [static]

Sets the brush used as background in the absence of obscuring windows, to be the given brush.

Note that this function can only be used in the server process.

See also backgroundBrush().

void QWSServer::setCurrentInputMethod ( QWSInputMethod * method )   [static]

Sets the current input method to be the given method.

Note that this function can only be used in the server process.

See also sendIMQuery() and sendIMEvent().

void QWSServer::setCursorVisible ( bool visible )   [static]

Shows the cursor if visible is true: otherwise the cursor is hidden.

Note that this function can only be used in the server process.

See also isCursorVisible().

void QWSServer::setDefaultKeyboard ( const char * keyboardDriver )   [static]

Sets the keyboard driver that will be used if the QWS_KEYBOARD environment variable is not defined, to be the given keyboardDriver.

Note that the default is platform-dependent. This function can only be used in the server process.

See also setKeyboardHandler() and Qt for Embedded Linux Character Input.

void QWSServer::setDefaultMouse ( const char * mouseDriver )   [static]

Sets the mouse driver that will be used if the QWS_MOUSE_PROTO environment variable is not defined, to be the given mouseDriver.

Note that the default is platform-dependent. This function can only be used in the server process.

See also setMouseHandler() and Qt for Embedded Linux Pointer Handling.

void QWSServer::setKeyboardHandler ( QWSKeyboardHandler * driver )   [static]

Sets the primary keyboard driver to be the given driver.

Qt for Embedded Linux provides several ready-made keyboard drivers, and custom drivers are typically added using Qt's plugin mechanism. See the Qt for Embedded Linux Character Input documentation for details.

Note that this function can only be used in the server process.

See also keyboardHandler() and setDefaultKeyboard().

void QWSServer::setMaxWindowRect ( const QRect & rectangle )   [static]

Sets the maximum area of the screen that Qt for Embedded Linux applications can use, to be the given rectangle.

Note that this function can only be used in the server process.

See also QWidget::showMaximized().

void QWSServer::setMouseHandler ( QWSMouseHandler * driver )   [static]

Sets the primary mouse driver to be the given driver.

Qt for Embedded Linux provides several ready-made mouse drivers, and custom drivers are typically added using Qt's plugin mechanism. See the Qt for Embedded Linux Pointer Handling documentation for details.

Note that this function can only be used in the server process.

See also mouseHandler() and setDefaultMouse().

void QWSServer::setScreenSaver ( QWSScreenSaver * screenSaver )   [static]

Installs the given screenSaver, deleting the current screen saver.

Note that this function can only be used in the server process.

See also screenSaverActivate(), setScreenSaverInterval(), setScreenSaverIntervals(), and setScreenSaverBlockLevel().

void QWSServer::setScreenSaverBlockLevel ( int eventBlockLevel )   [static]

Block the key or mouse event that wakes the system from level eventBlockLevel or higher. To completely disable event blocking (the default behavior), set eventBlockLevel to -1.

The algorithm blocks the "down", "up" as well as any "repeat" events for the same key but will not block other key events after the initial "down" event. For mouse events, the algorithm blocks all mouse events until an event with no buttons pressed is received.

There are 2 keys that are never blocked, Qt::Key_F34 (POWER) and Qt::Key_F35 (LIGHT).

Example usage:

 bool MyScreenSaver::save( int level )
 {
     switch ( level ) {
         case 0:
             if ( dim_enabled ) {
                 // dim the screen
             }
             return true;
         case 1:
             if ( screenoff_enabled ) {
                 // turn off the screen
             }
             return true;
         case 2:
             if ( suspend_enabled ) {
                 // suspend
             }
             return true;
         default:
             return false;
     }
 }

 ...

 int timings[4];
 timings[0] = 5000;  // dim after 5 seconds
 timings[1] = 10000; // light off after 15 seconds
 timings[2] = 45000; // suspend after 60 seconds
 timings[3] = 0;
 QWSServer::setScreenSaverIntervals( timings );

 // ignore the key/mouse event that turns on the screen
 int blocklevel = 1;
 if ( !screenoff_enabled ) {
     // screenoff is disabled, ignore the key/mouse event that wakes from suspend
     blocklevel = 2;
     if ( !suspend_enabled ) {
         // suspend is disabled, never ignore events
         blocklevel = -1;
     }
 }
 QWSServer::setScreenSaverBlockLevel( blocklevel );

Note that this function can only be used in the server process.

See also setScreenSaverIntervals() and setScreenSaverInterval().

void QWSServer::setScreenSaverInterval ( int milliseconds )   [static]

Sets the timeout interval for the screensaver to the specified milliseconds. To turn off the screensaver, set the timout interval to 0.

Note that this function can only be used in the server process.

See also setScreenSaverIntervals() and setScreenSaverBlockLevel().

void QWSServer::setScreenSaverIntervals ( int * intervals )   [static]

Specifies the time intervals (in milliseconds) between the different levels of screen responsiveness.

Qt for Embedded Linux supports multilevel screen saving, i.e., it is possible to specify several different levels of screen responsiveness by implementing the QWSScreenSaver::save() function. For example, you can choose to first turn off the light before you fully activate the screensaver. See the QWSScreenSaver documentation for details.

Note that an interval of 0 milliseconds will turn off the screensaver, and that the intervals array must be 0-terminated. This function can only be used in the server process.

See also setScreenSaverInterval() and setScreenSaverBlockLevel().

void QWSServer::suspendMouse ()

Suspends pointer handling by deactivating all the mouse drivers registered by the QWS_MOUSE_PROTO environment variable.

See also resumeMouse() and QWSMouseHandler::suspend().

QWSWindow * QWSServer::windowAt ( const QPoint & position )

Returns the window containing the given position.

Note that if there is no window under the specified point this function returns 0.

See also clientWindows() and instance().

void QWSServer::windowEvent ( QWSWindow * window, QWSServer::WindowEvent eventType )   [signal]

This signal is emitted whenever something happens to a top-level window (e.g., it's created or destroyed), passing a pointer to the window and the event's type in the window and eventType parameters, respectively.

See also markedText().