QMainPanel.cpp

#include <windows.h>

#include <QApplication>
#include <QGridLayout>
#include <QLabel>
#include <QPushButton>
#include <QScrollArea>
#include <QSpacerItem>

#include "QMainPanel.h"

#include <windowsx.h>

QMainPanel::QMainPanel( HWND hWnd ) : QWinWidget( hWnd ) {

  windowHandle = hWnd;

  setObjectName( "mainPanel" );

  // Horizontal layout
  QHBoxLayout *horizontalLayout = new QHBoxLayout;
  horizontalLayout->setSpacing( 0 );
  horizontalLayout->setMargin( 0 );

  // Window title
  QLabel *windowTitle = new QLabel( this );
  windowTitle->setObjectName( "windowTitle" );
  windowTitle->setText( "Borderless window" );
  windowTitle->setStyleSheet( "font-size: 16px; color: #444444;" );
  windowTitle->setAttribute( Qt::WA_TransparentForMouseEvents );
  horizontalLayout->addWidget( windowTitle );
  horizontalLayout->addStretch();

  // System buttons
  // Minimize
  QPushButton *pushButtonMinimize = new QPushButton( "", this );
  pushButtonMinimize->setObjectName( "pushButtonMinimize" );
  horizontalLayout->addWidget( pushButtonMinimize );
  QObject::connect( pushButtonMinimize, SIGNAL( clicked() ), this, SLOT( pushButtonMinimizeClicked() ) );

  // Maximize
  QPushButton *pushButtonMaximize = new QPushButton( "", this );
  pushButtonMaximize->setObjectName( "pushButtonMaximize" );
  horizontalLayout->addWidget( pushButtonMaximize );
  QObject::connect( pushButtonMaximize, SIGNAL( clicked() ), this, SLOT( pushButtonMaximizeClicked() ) );

  // Close
  QPushButton *pushButtonClose = new QPushButton( "", this );
  pushButtonClose->setObjectName( "pushButtonClose" );
  horizontalLayout->addWidget( pushButtonClose );
  QObject::connect( pushButtonClose, SIGNAL( clicked() ), this, SLOT( pushButtonCloseClicked() ) );

  // Main panel layout
  QGridLayout *mainGridLayout = new QGridLayout();
  mainGridLayout->setSpacing( 0 );
  mainGridLayout->setMargin( 0 );
  setLayout( mainGridLayout );

  // Central widget
  QWidget *centralWidget = new QWidget( this );
  centralWidget->setObjectName( "centralWidget" );
  centralWidget->setSizePolicy( QSizePolicy::Expanding, QSizePolicy::Expanding );

  // Main panel scroll area
  QScrollArea *scrollArea = new QScrollArea( this );
  scrollArea->setWidgetResizable( true );
  scrollArea->setObjectName( "mainPanelScrollArea" );
  scrollArea->setSizePolicy( QSizePolicy::Expanding, QSizePolicy::Expanding );
  scrollArea->setHorizontalScrollBarPolicy( Qt::ScrollBarAlwaysOff );
  scrollArea->setVerticalScrollBarPolicy( Qt::ScrollBarAsNeeded );

  // Vertical layout example
  QVBoxLayout *verticalLayout = new QVBoxLayout();
  verticalLayout->setSpacing( 0 );
  verticalLayout->setMargin( 0 );
  verticalLayout->setAlignment( Qt::AlignHCenter );
  verticalLayout->addLayout( horizontalLayout );

  // Label example
  QLabel *label = new QLabel( centralWidget );
  label->setObjectName( "Label" );
  label->setText( "Hello World! This is QLabel." );
  label->setStyleSheet( "font-size: 48px" );
  verticalLayout->addWidget( label );

  // Show
  centralWidget->setLayout( verticalLayout );
  scrollArea->setWidget( centralWidget );
  mainGridLayout->addWidget( scrollArea );

  show();
}

// Button events
void QMainPanel::pushButtonMinimizeClicked() {
  ShowWindow( parentWindow(), SW_MINIMIZE );
}

void QMainPanel::pushButtonMaximizeClicked() {
  WINDOWPLACEMENT wp;
  wp.length = sizeof( WINDOWPLACEMENT );
  GetWindowPlacement( parentWindow(), &wp );
  if ( wp.showCmd == SW_MAXIMIZE ) {
    ShowWindow( parentWindow(), SW_RESTORE );
  } else {
    ShowWindow( parentWindow(), SW_MAXIMIZE );
  }
}

void QMainPanel::pushButtonCloseClicked() {
  PostQuitMessage( 0 );
}

#if QT_VERSION >= 0x050000
  bool QMainPanel::nativeEvent( const QByteArray &, void *msg, long * ) {
#else
  bool QMainPanel::winEvent( MSG *message, long * ) {
#endif
#if QT_VERSION >= 0x050000
  MSG *message = ( MSG * )msg;
#endif
  switch( message->message ) {
    case WM_SYSKEYDOWN: {
      if ( message->wParam == VK_SPACE ) {
        SendMessage( windowHandle, WM_SYSKEYDOWN, VK_SPACE, message->lParam );
        return true;
      }
      return DefWindowProc( message->hwnd, message->message, message->wParam, message->lParam );
    }

    case WM_KEYDOWN: {
      if ( message->wParam == VK_F5 ||
           message->wParam == VK_F6 ||
           message->wParam == VK_F7
         ) {
        SendMessage( windowHandle, WM_KEYDOWN, message->wParam, message->lParam );
        break;
      }
    }
  }

  return false;
}

void QMainPanel::mousePressEvent( QMouseEvent *event ) {
  if ( event->button() == Qt::LeftButton ) {
     ReleaseCapture();
     SendMessage( windowHandle, WM_NCLBUTTONDOWN, HTCAPTION, 0 );
  }

  if ( event->type() == QEvent::MouseButtonDblClick ) {
    if (event -> button() == Qt::LeftButton) {
      WINDOWPLACEMENT wp;
      wp.length = sizeof( WINDOWPLACEMENT );
      GetWindowPlacement( parentWindow(), &wp );
      if ( wp.showCmd == SW_MAXIMIZE ) {
        ShowWindow( parentWindow(), SW_RESTORE );
      } else {
        ShowWindow( parentWindow(), SW_MAXIMIZE );
      }
    }
  }
}