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EventQtSlotConnect

vtk-examples/Cxx/Qt/EventQtSlotConnect


Question

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Code

EventQtSlotConnect.cxx

#include "EventQtSlotConnect.h"
#include "ui_EventQtSlotConnect.h"

#include <vtkEventQtSlotConnect.h>
#include <vtkGenericOpenGLRenderWindow.h>
#include <vtkInteractorStyleTrackballActor.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSphereSource.h>
#include <vtkVersion.h>

#if VTK_VERSION_NUMBER >= 89000000000ULL
#define VTK890 1
#endif

// Constructor
EventQtSlotConnect::EventQtSlotConnect(QWidget* parent)
  : QMainWindow(parent), ui(new Ui::EventQtSlotConnect)
{
  this->ui->setupUi(this);

  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkGenericOpenGLRenderWindow> renderWindow;
#if VTK890
  this->ui->qvtkWidget->setRenderWindow(renderWindow);
#else
  this->ui->qvtkWidget->SetRenderWindow(renderWindow);
#endif

  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);
  sphereActor->GetProperty()->SetColor(colors->GetColor4d("Tomato").GetData());

  // VTK Renderer
  vtkNew<vtkRenderer> renderer;
  renderer->AddActor(sphereActor);
  renderer->SetBackground(colors->GetColor3d("SteelBlue").GetData());

#if VTK890
  this->ui->qvtkWidget->renderWindow()->AddRenderer(renderer);
#else
  this->ui->qvtkWidget->GetRenderWindow()->AddRenderer(renderer);
#endif

#if VTK890
  this->Connections->Connect(
      this->ui->qvtkWidget->renderWindow()->GetInteractor(),
      vtkCommand::LeftButtonPressEvent, this,
      SLOT(slot_clicked(vtkObject*, unsigned long, void*, void*)));
#else
  this->Connections->Connect(
      this->qvtkWidget->GetRenderWindow()->GetInteractor(),
      vtkCommand::LeftButtonPressEvent, this,
      SLOT(slot_clicked(vtkObject*, unsigned long, void*, void*)));
#endif
};

EventQtSlotConnect::~EventQtSlotConnect()
{
  delete this->ui;
}

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

EventQtSlotConnectDriver.cxx

#include <QApplication>
#include <QSurfaceFormat>

#include <QVTKOpenGLNativeWidget.h>

#include "EventQtSlotConnect.h"

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

  QApplication app(argc, argv);

  EventQtSlotConnect eventQtSlotConnect;
  eventQtSlotConnect.show();

  return app.exec();
}

EventQtSlotConnect.h

#ifndef EventQtSlotConnect_H
#define EventQtSlotConnect_H

#include <QMainWindow>

#include <vtkObject.h>
#include <vtkSmartPointer.h>

// Forward class declarations
class vtkEventQtSlotConnect;

/*
 * See "The Single Inheritance Approach" in this link:
 * [Using a Designer UI File in Your C++
 * Application](https://doc.qt.io/qt-5/designer-using-a-ui-file.html)
 */
namespace Ui {
class EventQtSlotConnect;
}

class EventQtSlotConnect : public QMainWindow
{
  Q_OBJECT
public:
  explicit EventQtSlotConnect(QWidget* parent = nullptr);
  virtual ~EventQtSlotConnect();

public slots:

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

private:
  vtkSmartPointer<vtkEventQtSlotConnect> Connections;
  // Designer form
  Ui::EventQtSlotConnect* ui;
};

#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="QVTKOpenGLNativeWidget" 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>QVTKOpenGLNativeWidget</class>
   <extends>QWidget</extends>
   <header>QVTKOpenGLNativeWidget.h</header>
  </customwidget>
 </customwidgets>
 <resources/>
 <connections/>
</ui>

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

if(POLICY CMP0020)
  cmake_policy(SET CMP0020 NEW)
  cmake_policy(SET CMP0071 NEW)
endif()

PROJECT(EventQtSlotConnect)

find_package(VTK COMPONENTS 
  vtkCommonColor
  vtkCommonCore
  vtkFiltersSources
  vtkGUISupportQt
  vtkInteractionStyle
  vtkRenderingContextOpenGL2
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingGL2PSOpenGL2
  vtkRenderingOpenGL2
  vtkGUISupportQt
  vtkRenderingQt
  QUIET
)

if(NOT VTK_FOUND)
  message(FATAL_ERROR "EventQtSlotConnect: ${VTK_NOT_FOUND_MESSAGE}")
endif()

if(NOT(vtkGUISupportQt_LOADED OR TARGET VTK::GUISupportQt))
  message(FATAL_ERROR "EventQtSlotConnect: VTK not built with Qt support.")
endif()

if(NOT DEFINED VTK_QT_VERSION)
  set(VTK_QT_VERSION 5)
endif()

set(qt_components Core Gui Widgets)
if(${VTK_QT_VERSION} VERSION_GREATER_EQUAL 6)
  list(APPEND qt_components OpenGLWidgets)
endif()
list(SORT qt_components)
# We have ui files, so this will also bring in the macro:
#   qt5_wrap_ui or qt_wrap_ui from Widgets.
find_package(Qt${VTK_QT_VERSION} QUIET
  REQUIRED COMPONENTS ${qt_components}
)

foreach(_qt_comp IN LISTS qt_components)
  list(APPEND qt_modules "Qt${VTK_QT_VERSION}::${_qt_comp}")
endforeach()

message (STATUS "VTK_VERSION: ${VTK_VERSION}, Qt Version: ${Qt${VTK_QT_VERSION}Widgets_VERSION}")

if (VTK_VERSION VERSION_LESS "8.90.0")
# Instruct CMake to run moc automatically when needed.
  set(CMAKE_AUTOMOC ON)
else()
# Instruct CMake to run moc and uic automatically when needed.
  set(CMAKE_AUTOMOC ON)
  set(CMAKE_AUTOUIC ON)
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)

# For VTK versions greater than or equal to 8.90.0:
#  CMAKE_AUTOUIC is ON so we handle uic automatically for Qt targets.
#  CMAKE_AUTOMOC is ON so we handle moc automatically for Qt targets.
# However we have to do the following for VTK versions less than 8.90.0,
#  and we also assume, in this case, that Qt5 is being used.
if (VTK_VERSION VERSION_LESS "8.90.0")
  qt5_wrap_ui(UISrcs ${EXAMPLE}.ui)
endif()

if (VTK_VERSION VERSION_LESS "8.90.0")
  # old system
  include(${VTK_USE_FILE})
  # CMAKE_AUTOMOC in ON so the MOC headers will be automatically wrapped.
  add_executable(EventQtSlotConnect MACOSX_BUNDLE
    ${CXX_FILES} ${UISrcs} ${QT_WRAP})
  if (Qt${VTK_QT_VERSION}Widgets_VERSION VERSION_LESS "5.11.0")
    qt5_use_modules(EventQtSlotConnect ${qt_components})
  else()
    target_link_libraries(EventQtSlotConnect ${qt_modules})
  endif()
  target_link_libraries(EventQtSlotConnect ${VTK_LIBRARIES})
else()
  # CMAKE_AUTOMOC in ON so the MOC headers will be automatically wrapped.
  add_executable(EventQtSlotConnect MACOSX_BUNDLE
    ${CXX_FILES} ${UISrcs} ${QT_WRAP})
  if (Qt${VTK_QT_VERSION}Widgets_VERSION VERSION_LESS "5.11.0")
    qt5_use_modules(EventQtSlotConnect ${qt_components})
  else()
    target_link_libraries(EventQtSlotConnect ${qt_modules})
  endif()
  target_link_libraries(EventQtSlotConnect ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS EventQtSlotConnect
    MODULES ${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.