# EventQtSlotConnect

VTKExamples/Cxx/Qt/EventQtSlotConnect

### Code

EventQtSlotConnect.cxx

    #include "EventQtSlotConnect.h"

    #include "vtkGenericOpenGLRenderWindow.h"
    #include <vtkNew.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkRenderer.h>
    #include <vtkRenderWindow.h>
    #include <vtkSphereSource.h>
    #include <vtkEventQtSlotConnect.h>
    #include <vtkInteractorStyleTrackballActor.h>

    // Constructor
    EventQtSlotConnect::EventQtSlotConnect()
    {
      this->setupUi(this);
      vtkNew<vtkGenericOpenGLRenderWindow> renderWindow;
      this->qvtkWidget->SetRenderWindow(renderWindow);

      vtkNew<vtkEventQtSlotConnect> slotConnector;
      this->Connections = slotConnector;

      // Sphere
      vtkNew<vtkSphereSource> sphereSource;
      sphereSource->Update();
      vtkNew<vtkPolyDataMapper> sphereMapper;
      sphereMapper->SetInputConnection(sphereSource->GetOutputPort());

      vtkNew<vtkActor> sphereActor;
      sphereActor->SetMapper(sphereMapper);

      // VTK Renderer
      vtkNew<vtkRenderer> renderer;
      renderer->AddActor(sphereActor);

      this->qvtkWidget->GetRenderWindow()->AddRenderer(renderer);

      this->Connections->Connect(this->qvtkWidget->GetRenderWindow()->GetInteractor(),
      vtkCommand::LeftButtonPressEvent,
      this,
      SLOT(slot_clicked(vtkObject*, unsigned long, void*, void*)));

    };

    void EventQtSlotConnect::slot_clicked(vtkObject*, unsigned long, void*, void*)
    {
      std::cout << "Clicked." << std::endl;
    }

EventQtSlotConnectDriver.cxx

    #include <QApplication>
    #include <QSurfaceFormat>
    #include "EventQtSlotConnect.h"

    int main(int argc, char** argv)
    {
      // needed to ensure appropriate OpenGL context is created for VTK rendering.
      QSurfaceFormat::setDefaultFormat(QVTKOpenGLWidget::defaultFormat());

      QApplication app(argc, argv);

      EventQtSlotConnect eventQtSlotConnect;
      eventQtSlotConnect.show();

      return app.exec();
    }

EventQtSlotConnect.h

    #ifndef EventQtSlotConnect_H
    #define EventQtSlotConnect_H

    #include "ui_EventQtSlotConnect.h"

    #include <QMainWindow>

    #include <vtkSmartPointer.h>
    class vtkEventQtSlotConnect;

    class EventQtSlotConnect : public QMainWindow, private Ui::EventQtSlotConnect
    {
      Q_OBJECT
    public:

      EventQtSlotConnect();

    public slots:

      void slot_clicked(vtkObject*, unsigned long, void*, void*);

    private:

      vtkSmartPointer<vtkEventQtSlotConnect> Connections;
    };

    #endif

EventQtSlotConnect.ui

    <?xml version="1.0" encoding="UTF-8"?>
    <ui version="4.0">
     <class>EventQtSlotConnect</class>
     <widget class="QMainWindow" name="EventQtSlotConnect">
      <property name="geometry">
       <rect>
        <x>0</x>
        <y>0</y>
        <width>561</width>
        <height>575</height>
       </rect>
      </property>
      <property name="windowTitle">
       <string>EventQtSlotConnect</string>
      </property>
      <widget class="QWidget" name="centralwidget">
       <layout class="QHBoxLayout" name="horizontalLayout">
        <item>
         <widget class="QVTKOpenGLWidget" name="qvtkWidget">
          <property name="sizePolicy">
           <sizepolicy hsizetype="Expanding" vsizetype="MinimumExpanding">
            <horstretch>0</horstretch>
            <verstretch>0</verstretch>
           </sizepolicy>
          </property>
         </widget>
        </item>
       </layout>
      </widget>
      <action name="actionOpenFile">
       <property name="enabled">
        <bool>true</bool>
       </property>
       <property name="text">
        <string>Open File...</string>
       </property>
      </action>
      <action name="actionExit">
       <property name="text">
        <string>Exit</string>
       </property>
      </action>
      <action name="actionPrint">
       <property name="text">
        <string>Print</string>
       </property>
      </action>
      <action name="actionHelp">
       <property name="text">
        <string>Help</string>
       </property>
      </action>
      <action name="actionSave">
       <property name="text">
        <string>Save</string>
       </property>
      </action>
     </widget>
     <customwidgets>
      <customwidget>
       <class>QVTKOpenGLWidget</class>
       <extends>QWidget</extends>
       <header>QVTKOpenGLWidget.h</header>
      </customwidget>
     </customwidgets>
     <resources/>
     <connections/>
    </ui>

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    if(POLICY CMP0020)
      cmake_policy(SET CMP0020 NEW)
    endif()

    PROJECT(EventQtSlotConnect)

    find_package(VTK REQUIRED)
    include(${VTK_USE_FILE})

    if(${VTK_VERSION} VERSION_GREATER "6" AND VTK_QT_VERSION VERSION_GREATER "4")
      # Instruct CMake to run moc automatically when needed.
      set(CMAKE_AUTOMOC ON)
      find_package(Qt5Widgets REQUIRED QUIET)
    else()
      find_package(Qt4 REQUIRED)
      include(${QT_USE_FILE})
    endif()

    include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR})

    file(GLOB UI_FILES *.ui)
    file(GLOB QT_WRAP *.h)
    file(GLOB CXX_FILES *.cxx)

    if(${VTK_VERSION} VERSION_GREATER "6" AND VTK_QT_VERSION VERSION_GREATER "4")
      qt5_wrap_ui(UISrcs ${UI_FILES} )
      # CMAKE_AUTOMOC in ON so the MOC headers will be automatically wrapped.
      add_executable(EventQtSlotConnect MACOSX_BUNDLE
        ${CXX_FILES} ${UISrcs} ${QT_WRAP})
      qt5_use_modules(EventQtSlotConnect Core Gui)
      target_link_libraries(EventQtSlotConnect ${VTK_LIBRARIES})
    else()
      QT4_WRAP_UI(UISrcs ${UI_FILES})
      QT4_WRAP_CPP(MOCSrcs ${QT_WRAP})
      add_executable(EventQtSlotConnect MACOSX_BUNDLE ${CXX_FILES} ${UISrcs} ${MOCSrcs})
      target_link_libraries(EventQtSlotConnect ${VTK_LIBRARIES})
    endif()

### Download and Build EventQtSlotConnect

Click here to download EventQtSlotConnect and its CMakeLists.txt file. Once the tarball EventQtSlotConnect.tar has been downloaded and extracted,

     cd EventQtSlotConnect/build

This example requires Qt and VTK.

If VTK and Qt are installed:

     cmake ..

If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:

     cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

If Qt is not found on your system, you will need to tell CMake where to find qmake:

    cmake -DQT_QMAKE_EXECUTABLE:FILEPATH=/usr/something/qmake  ..

Build the project:

    make

and run it:

    ./EventQtSlotConnect

WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time. You may also need to add a Qt related path.