Foundations of Qt Development\Chapter06\eventfilter\main.cpp
/*
* Copyright (c) 2006-2007, Johan Thelin
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of APress nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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*/
#include <QApplication>
#include <QLineEdit>
#include <QKeyEvent>
class KeyboardFilter : public QObject
{
public:
KeyboardFilter( QObject *parent = 0 ) : QObject( parent ) {}
protected:
bool eventFilter( QObject *dist, QEvent *event )
{
if( event->type() == QEvent::KeyPress )
{
QKeyEvent *keyEvent = static_cast<QKeyEvent*>( event );
if( QString("1234567890").indexOf( keyEvent->text() ) != -1 )
return true;
}
return false;
}
};
int main( int argc, char **argv )
{
QApplication app( argc, argv );
QLineEdit lineEdit;
KeyboardFilter filter;
lineEdit.installEventFilter( &filter );
lineEdit.show();
return app.exec();
}
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