Qt/Utilities/EventFilter

main.cpp

#include <QProgressDialog>
#include <QApplication>
 
#include "form.h"
 
int main( int argc, char **argv )
{
  QApplication app(argc, argv);
  MainWindow window;
 
  window.show();
 
  return app.exec();
}

form.h

#ifndef FORM_H
#define FORM_H
 
#include "ui_main.h"
 
#include <QTime>
 
class MainWindow : public QMainWindow, public Ui::MainWindow
{
Q_OBJECT
 
public:
  MainWindow();
  bool eventFilter(QObject *object, QEvent *event);
};
 
#endif

form.cpp

#include "form.h"
 
// Qt
#include <QtGui>
#include <QEvent>
 
// STL
#include <iostream>
 
MainWindow::MainWindow()
{
  setupUi(this);
  lineEdit->installEventFilter(this);
}
 
 bool MainWindow::eventFilter(QObject *object, QEvent *event)
 {
  if (object == lineEdit && event->type() == QEvent::FocusOut)
  {
    std::cout << "eventFilter" << std::endl;
  }
  return false; // Pass the event along (don't consume it)
 }

form.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>571</width>
    <height>500</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralwidget">
   <layout class="QVBoxLayout" name="verticalLayout">
    <item>
     <widget class="QLineEdit" name="lineEdit"/>
    </item>
    <item>
     <widget class="QLabel" name="label">
      <property name="text">
       <string>TextLabel</string>
      </property>
     </widget>
    </item>
   </layout>
  </widget>
 </widget>
 <resources/>
 <connections/>
</ui>

CMakeLists.txt

cmake_minimum_required(VERSION 2.6)
 
PROJECT(EventFilter)
 
FIND_PACKAGE(Qt4 REQUIRED)
INCLUDE(${QT_USE_FILE})
 
QT4_WRAP_UI(UISrcs main.ui)
QT4_WRAP_CPP(MOCSrcs form.h)
 
include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR})
 
ADD_EXECUTABLE(EventFilter main.cpp form.cpp ${UISrcs} ${MOCSrcs})
TARGET_LINK_LIBRARIES(EventFilter ${QT_LIBRARIES})